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Oxido iron(IV) complexes are key intermediates in oxygenation reactions in biological systems. They can form during oxidation experiments with various oxidants such as oxygen, hydrogen peroxide, organoiodine compounds, or ozone. However, kinetic studies for these reactions are rare because the intermediates are usually labile. Here the results of a detailed investigation on the oxidation of iron(II) complexes with macrocyclic (e.g. TMC = tetramethylcyclam = 1,4,8,11-tetramethyl-1,4,8,11-tetraaza-cyclotetradecane) ligands are reported that provide a better understanding of the mechanisms of these reactions. For formation of the quite stable oxido iron complex with an amide derivative of TMC, activation parameters with ΔH‡ = 28 ± 4 kJ·mol−1 and ΔS‡ = −144 ± 15 J·mol−1·K−1 could be obtained that allowed postulation of an associative mechanism.

Direct oxidation of silyl ethers to silyl esters, using RuO4 formed in situ, is reported. The reaction was optimized to minimize formation of the corresponding carboxylic acid product whose formation pathway appears to be solvent dependent. The reaction is tolerant of halides, nitriles, nitro groups, esters, epoxides, and ketones.

Background A psychosocial evaluation is an important component of the preoperative assessment process for people seeking metabolic and bariatric surgery (MBS), and is required for accreditation of MBS programs. Recently, independent companies without affiliations with MBS programs have been marketing remotely administered, unaffiliated psychosocial evaluations for MBS (RUS), and American Society for Metabolic and Bariatric Surgery (ASMBS) members have raised concerns about these evaluations. Objectives To explore ASMBS members’ beliefs about RUS. Setting Online survey. Methods We developed a survey to evaluate ASMBS members’ opinions, experiences, and/or concerns about in-person and RUS psychosocial evaluations for MBS. Results In total, 635 ASMBS members responded to the online survey and 156 responded to an open-ended question on RUS. Responses were coded based on a manual developed for this study, yielding themes of concerns about the quality of RUS, lack of ongoing relationships in RUS, and conditions under which/reasons why RUS evaluations could be acceptable. Conclusion Respondents expressed both interest in and concerns about RUS in pre-MBS psychosocial evaluations. Use of RUS has the potential to improve access to MBS by providing a convenient and efficient means of completing the psychosocial evaluation. Conversely, respondents expressed concerns about the background and training of RUS providers, the quality of the reports, and the limited relationships between the RUS provider and both the MBS patient and the MBS team. We discuss the clinical and research implications of response themes, particularly for patients in rural areas or those who have other barriers to care.

Area-selective thin film deposition is expected to be important in achieving sub-10 nm semiconductor devices, enabling feature patterning, alignment to underlying structures, and edge definition. Atomic layer deposition (ALD) offers advantages over common chemical vapor deposition methods, such as precise thickness control and excellent conformality. Furthermore, several ALD processes show inherent propensity for substrate-dependent nucleation. For example, tungsten ALD using SiH4 (or Si2H6) and WF6 is more energetically favorable on Si than on SiO2, but selectivity is often lost after several ALD cycles. We show that modifying the W ALD process chemistry can decrease the W nucleation rate on SiO2, thereby expanding the ALD “selectivity window”. Specifically, we find that adding H2 during the WF6 dose step helps passivate SiO2 against W nucleation without modifying W growth on silicon. Surface characterization confirms that H2 promotes fluorine passivation of SiO2, likely through surface reactions with HF...

Summary Background Antiretroviral therapy (ART) management is challenging for individuals in resource-limited settings presenting for third-line treatment because of complex resistance patterns, partly due to reduced access to viral load monitoring. We aimed to evaluate use of newer antiretroviral drugs and contemporary management approaches, including population-based sequencing, to select appropriate antiretrovirals, plasma viral load monitoring, and interventions to improve adherence in individuals presenting with second-line viral failure. Methods A5288 was a phase 4, third-line ART strategy study done at 19 urban sites in ten countries that enrolled adult participants with confirmed plasma HIV-1 RNA (viral load) of 1000 copies per mL or more after more than 24 weeks of protease inhibitor-based second-line ART. The primary objective was to use antiretrovirals (raltegravir, etravirine, and ritonavir-boosted darunavir) and diagnostic monitoring technologies, including viral load, genotyping, and adherence support to achieve viral load suppression (defined as ≤200 copies per mL) in 65% or more of participants. ART history and real-time drug resistance genotypes were used to assign participants to one of four cohorts: cohort A (no lopinavir resistance) stayed on second-line ART and cohorts B (B1, best available nucleoside reverse transcriptase inhibitors [NRTIs] plus ritonavir-boosted darunavir plus raltegravir; B2, ritonavir-boosted darunavir plus raltegravir plus etravirine; B3, ritonavir-boosted darunavir, raltegravir, and either tenofovir plus emtricitabine or tenofovir plus lamivudine), C (ritonavir-boosted darunavir plus raltegravir plus tenofovir-emtricitabine or tenofovir plus lamivudine), and D (best available NRTIs plus ritonavir-boosted darunavir plus raltegravir) were defined by increasing levels of resistance and received appropriate regimens, including new antiretrovirals. Participants in Cohort B without detectable hepatitis B surface antigen were assigned by blocked randomisation to cohorts B1 and B2, and those with detectable hepatitis B surface antigen were assigned to cohort B3. The trial is registered with ClinicalTrials.gov , number NCT01641367 . Findings From Jan 10, 2013, to Sept 10, 2015, 545 participants were enrolled. 287 (53%) were assigned to cohort A, 74 (14%) to B1, 72 (13%) to B2, eight (1%) to B3, 70 (13%) to C, and 34 (6%) to D. Overall, 349 (64%, 95% CI 60–68) participants achieved viral suppression at week 48, with proportions varying from 125 (44%) of 287 in cohort A to 65 (88%) of 74 in cohort B1, 63 (88%) of 72 in B2, eight (100%) of eight in B3, 63 (90%) of 70 in C, and 25 (74%) of 34 in D. Participants in cohort A remained on their second-line protease inhibitor, and had the most participants with grade 3 or higher adverse events (147 [51%]). Interpretation Targeted real-time genotyping to select third-line ART can appropriately allocate more costly antiretrovirals to those with greater levels of HIV drug resistance. Funding National Institutes of Health.

Serious Candida glabrata infections, which can be difficult to treat, are often treated with echinocandins. We compared in vitro the effects of high and low concentrations of 3 echinocandins (micafungin [MCF], caspofungin [CAS], and anidulafungin [ANF]), voriconazole (VRC), and amphotericin B (AmB), singly and VRC in combination with MCF, CAS, and ANF, on the production of cytokines/chemokines by human monocyte-derived macrophages (MDM). MDM were activated by infection with C. glabrata or lipopolysaccharide (LPS). Luminex multi-analyte microsphere technology was used for cytokine/chemokine analysis. Concentrations of cytokines/chemokines were significantly elevated following activation by infection or LPS. Treatment with high concentrations of echinocandins, singly or in combination with VRC, was most effective in lowering the elevated cytokine/chemokine levels. This effect occurred only with MDM activated by infection with C. glabrata and not with LPS. Treatment with VRC or AmB alone had little or no effect on cytokine/chemokine levels. In severe C. glabrata infection associated with very high concentrations of dysregulated cytokines/chemokines, echinocandins, singly or in combination with VRC, may decrease cytokine/chemokine concentrations and thus may improve host survival.

Background:Candida glabrata causes infections associated with severe sepsis, production of high concentrations of cytokines/chemokines, and high mortality. This study describes the effects of anidulafungin (ANF) and voriconazole (VRC), singly and in combination, on the production of eight cytokines/chemokines by human monocyte-derived macrophages (MDM) infected with C. glabrata or activated by lipopolysaccharide (LPS). Methods: MDM monolayers were established, infected with C. glabrata or activated with LPS, and then treated with high or low concentrations of ANF, VRC, or both. Cytokine/chemokine levels in MDM supernatants were determined. Results: Levels of cytokines/chemokines were significantly elevated in supernatants of infected or LPS-activated MDM. Except for interleukin-10, all significant decreases in cytokine/chemokine concentrations (p < 0.01) occurred in supernatants of infected MDM treated with high concentrations of ANF or ANF + VRC. Conclusions: Decreases in cytokine/chemokine levels in supernatants of infected MDM treated with high concentrations of ANF or ANF + VRC suggest that similar treatment could improve survival in patients with severe, invasive C. glabrata infections and markedly elevated levels of serum cytokines/chemokines.

The purpose of this study was to determine by time-kill methodology the anticandidal effectiveness and durability of micafungin (MCF) and voriconazole (VRC), singly and in combination, against Candida glabrata (Cgl), intracellularly in human monocyte-derived macrophages and extracellularly in RPMI-MOPS broth with and without fetal calf serum (FCS) or pooled human serum (PHS). The anticandidal activity of MCF was concentration-dependent and durable. Combinations of MCF + VRC both intra- and extracellularly were more effective than single drugs. However, in extracellular experiments, FCS, and even more PHS, significantly decreased the anticandidal activity of MCF and VRC. Our in vitro studies suggest that MCF alone may be adequate where protein concentration is low (intracellular or extravascular sites), while MCF + VRC combinations may be preferred where protein concentration is high such as in the intravascular space.

The activity of tigecycline against Legionellae, which are intracellular pathogens, was evaluated intracellularly in human phagocytes and extracellularly, and compared to the activities of erythromycin and levofloxacin. Clinical isolates of L. pneumophila serogroups 1, 5, and 6 and L. micdadei were tested in time-kill experiments. Extracellular experiments were done using buffered yeast extract broth. For intracellular assays, monolayers of human monocyte-derived macrophages (MDM) were infected with L. pneumophila or L. micdadei. Antibiotics (0.05-2.5 × MIC) were then added. MDM were lysed at 0, 24, 48, and 72 h and viable bacteria in the lysates were enumerated. Based on multiples of the MICs, tigecycline was less active extracellularly than levofloxacin or erythromycin. However, intracellular killing of both L. pneumophila and L. micdadei by tigecycline at 72 h was greater than for erythromycin or levofloxacin. Currently, evidence does not support the use of tigecycline as a first-line drug for treatment of Legionella infections. However, since Legionellae are intracellular pathogens, these results suggest that tigecycline should be effective for treatment of infections caused by these bacteria.

We investigated the antistaphylococcal activity of daptomycin, vancomycin, oxacillin, gentamicin, and rifampin in human monocyte-derived macrophages. Compared with vancomycin and oxacillin, daptomycin had the most rapid and greatest antibacterial activity, but that of oxacillin was most sustained. The combination of daptomycin, gentamicin, and rifampin was most effective intracellularly, while daptomycin plus gentamicin and the three-drug combination were most effective extracellularly, completely eliminating viable Staphylococcus aureus .

Infections caused byCandidaspecies other thanCandida albicansare increasingly common, and decreased susceptibility to azoles has made them more difficult to treat. Since phagocytic killing is important in elimination ofCandidainfections, intracellular killing of fluconazole-resistantCandida glabrata,Candida kruseiandCandida parapsilosis(four strains each) by voriconazole was investigated in human monocyte-derived macrophages (MDMs). MDMs were infected withCandida, and voriconazole was then added. MDMs were lysed at 0, 24 or 48 h after infection, and viableCandidain the lysates enumerated. Compared to the starting inoculum, the number of viable intracellularC. parapsilosisandC. glabratain untreated MDMs increased to 28 121 and 351 %, respectively, in 48 h. In contrast, the number ofC. kruseidecreased to 42 %. In MDMs treated with voriconazole, the decrease in viable count was dependent upon drug concentration. At 48 h,C. glabratawas killed only at 5× MIC (PC. kruseiwas killed at all voriconazole concentrations, whileC. parapsilosiswas inhibited at 0.5 and 1× MIC and killed at ⩾2.5× MIC (PCandidaspecies in the absence or presence of voriconazole vary markedly. The activity of voriconazole depends on the concentration of the drug and the time of exposure. For the 12Candidastrains studied, regression curves show that the maximum intracellular anticandidal activity of voriconazole was reached at 3.5–5× MIC.

Nonsurgical weight management strategies have been largely unsuccessful in treating and reducing the prevalence of morbid obesity. Bariatric surgery has developed into a viable and successful long-term option for the morbidly obese patient. Unfortunately, bariatric surgery does not address the psychosocial, emotional, behavioral, and lifestyle challenges that often await many patients as they move through their weight loss. Patients may expect that their weight loss journey will be hurdle-free. The prebariatric surgery psychological evaluation can help identify the risk factors that might become barriers to optimal weight loss postsurgery. Components of the assessment may include developmental history, degree of social integration, willingness to access meaningful support, past and present psychiatric history, the presence of unusual life stressors, coping skills, and psychological resources. Other variables to be assessed include the presence of significant psychological eating, the onset of obesity, mai...

Infections caused by fluconazole-resistant Candida glabrata and Candida krusei are increasingly common causes of morbidity and mortality. We investigated the intracellular killing of fluconazole-resistant C. glabrata and C. krusei by cytokine-activated human monocyte-derived macrophages (MDM) in the presence and absence of voriconazole. For C. glabrata , MDM were activated with either granulocyte-macrophage colony-stimulating factor (GM-CSF) or interferon γ (IFN-γ) before infection, after infection, or both before and after infection, whereas for C. krusei MDM were activated with cytokines both before and after infection. Activated MDM were infected, treated with voriconazole, and then lysed, and viable yeast in the lysates enumerated at 0, 24, or 48 h after infection. In the presence of voriconazole (2.5 × MIC), the best activity against C. glabrata occurred when MDM were activated with GM-CSF for 24 h before infection as well as after infection or when they were activated for 24 h before infection alone. A lesser effect was observed when MDM were activated for at least 1 h before infection or when they were treated with cytokines only after infection. IFN-γ activation had a significant but lesser effect than GM-CSF. Activity against C. krusei in the presence of voriconazole was greatest when MDM were activated with IFN-γ rather than GM-CSF. Our results suggest that cytokines increase the intracellular anticandidal effect of voriconazole and may be useful as therapeutic adjuvants to voriconazole for treatment of infections caused by fluconazole-resistant C. glabrata and C. krusei .

Although antibiotics are known to affect the intracellular growth of Chlamydia pneumoniae in acute infections, their efficacy in therapy for chronic infections, including atherosclerosis, remains debatable. Human monocyte-derived macrophages (MDM) obtained from monocytes of healthy donors were infected with C. pneumoniae AR-39 and treated with levofloxacin (8 microg/mL) immediately after infection (0 hours) or 24 hours after infection. Levofloxacin treatment at 24 hours, but not at 0 hours, resulted in a significant decrease in the number of C. pneumoniae inclusions within the MDM (p < 0.05). Also decreased were concentrations of proinflammatory cytokines tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta, IL-6, and IL-8 in the extracellular medium (p < 0.01). Viable counts in titrations remained similar to those in untreated controls. In summary, levofloxacin administered to MDM at serum-attainable levels 24 hours after C. pneumoniae infection significantly decreased inclusion counts and proinflammatory cytokine production, but did not eliminate the C. pneumoniae infection.

Background:Chlamydia pneumoniae is known to cause acute respiratory infection and more recently it has been studied as a pathogen causing inflammatory changes in chronic diseases such as atherosclerosis. This study addresses the antichlamydial effect of levofloxacin and its role in modulation of a proinflammatory cytokine IL-6 production by uninfected and infected HEp-2 cells. Methods: HEp-2 cell monolayers were infected with previously prepared and frozen aliquots of C. pneumoniae [1 × 103 inclusion-forming units (IFU)/ml] by centrifugation for 30 min and incubation at 37°C for 1 h. Infected monolayers were treated with levofloxacin (3 or 8 µg/ml) immediately after infection (0 h) or 24 h after infection. Monolayers were examined daily for 96 h after infection by counting inclusions with fluorescently labeled antichlamydial monoclonal antibody. Aliquots of disrupted monolayers were titrated to determine the numbers of viable C. pneumoniae IFU/ml. IL-6 concentrations in cell supernatants were determined by ELISA assays. Results: Infected HEp-2 cells produced IL–6. Noninfected HEp-2 cells demonstrated modulation of IL-6 production by levofloxacin. No viable C. pneumoniae were detected in infected HEp-2 cells when the monolayer was treated with levofloxacin immediately after infection (0 h). In contrast, when cells were treated 24 h after infection, a gradual decline in the number of viable C. pneumoniae occurred; by 96 h into the assay ≧98% of C. pneumoniae were killed. IL-6 concentrations were similar in the supernatants of levofloxacin-treated and nontreated HEp-2 cells. Conclusions: (1) Levofloxacin is effective in eliminating C. pneumoniae from infected HEp-2 cells; (2) although levofloxacin modulates the production of IL-6 in untreated HEp-2 cells, no evidence for such modulation was observed in HEp-2 cells infected with C. pneumoniae. (3) Presence of viable C. pneumoniae may not be necessary for IL-6 production by infected and treated HEp-2 cells.

Altersschatzungen mussen immer haufiger an Individuen durchgefuhrt werden, die in ihrer biologischen und soziokulturellen Herkunft nicht der Population entsprechen, an dem das Referenzmaterial erhoben wurde. Bei der biochemischen Altersschatzung aufgrund des Razemisierungsgrades von Asparaginsaure in Dentin waren genetische bzw. soziokulturell bedingte Einflusse als Fehlerquellen theoretisch denkbar, wenn dadurch Variationen der Proteinkomposition des Dentins bedingt wurden. Zur Klarung der Frage, ob solche Einflusse tatsachlich zu berucksichtigen sind, wurden Zahne von turkischen und deutschen Individuen mit bekanntem Alter im unmittelbaren Vergleich untersucht. Die Beziehung zwischen dem Razemisierungsgrad von Asparaginsaure in Dentin und dem Dentinalter war in den untersuchten Kollektiven gleich. Auch unter Berucksichtigung der einschlagigen Literatur ergibt sich derzeit kein Anhaltspunkt dafur, dass genetische bzw. soziokulturelle Einflusse auf die Dentinproteinkomposition bei der biochemischen Altersschatzung berucksichtigt werden mussen.

This study evaluates the effects of cytokines, used singly and in combination, on the microbicidal activity of human monocyte-derived macrophages (MDM) against intracellular Candida albicans in the presence and absence of fluconazole. In the absence of fluconazole, the addition of tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), gamma interferon (IFN-γ), or IL-4 had no effect on the growth of C. albicans . In contrast, the addition of granulocyte-macrophage colony-stimulating factor (GM-CSF) resulted in decreased growth ( P < 0.05), while the addition of IL-10 resulted in increased growth ( P < 0.01). In the presence of fluconazole, only the addition of IFN-γ resulted in an increase in the growth of C. albicans . In the presence or absence of fluconazole, all cytokine combinations except IFN-γ plus GM-CSF caused significant decreases in growth ( P < 0.01). IL-10 and IL-4 did not influence the activity of TNF-α or IL-1β. In the absence or presence of C. albicans the addition of fluconazole, all of the cytokines studied, and combinations of fluconazole and selected cytokines caused increases in nitric oxide (NO) production ( P < 0.01). Similar observations were made for superoxide (O 2 − ) only in the presence of C. albicans . The greatest concentrations of NO and O 2 − were produced when C. albicans alone was present in the assays. Our results demonstrate that in the presence of low concentrations of fluconazole (0.1 times the MIC), selected cytokines and their combinations significantly increase the microbicidal activity of MDM against intracellular C. albicans .

BACKGROUND Because breast-conserving surgery (BCS), mastectomy alone, and mastectomy with reconstruction are equally effective for the treatment of early stage breast carcinoma, women's choice among them often focuses on quality-of-life (QOL) issues. Information regarding QOL after these surgical treatments could help women with this decision. METHODS Participants in this prospective study were women, age 30–85 years, with newly diagnosed breast carcinoma who underwent BCS (n = 103), mastectomy alone (n = 55), or mastectomy with reconstruction (n = 40). Quality of life was assessed after diagnosis (baseline) and at 1, 3, 6, 12, 18, and 24 months after baseline by using the Mischel Uncertainty in Illness Scale, Profile of Mood States, and Functional Assessment of Cancer Therapy for Breast Cancer. RESULTS In multivariate regression analyses controlling for the QOL score obtained at baseline, age, and type of nonsurgical treatment, women who underwent mastectomy with reconstruction had greater mood disturbance (P = 0.002) and poorer well-being (P = 0.002) after baseline than women who had mastectomy alone; these differences remained 18 months after surgery. Although similar analyses also showed that women who underwent BCS had more mood disturbance than women who had mastectomy alone, this difference was significant only at 12 months after baseline. The BCS and mastectomy-only group did not differ significantly regarding well-being. CONCLUSIONS Aspects of QOL other than body image are not better in women who undergo BCS or mastectomy with reconstruction than in women who have mastectomy alone. In fact, mastectomy with reconstruction is associated with greater mood disturbance and poorer well-being. Cancer 2001;91:1238–46. © 2001 American Cancer Society.

We consider a bivariate regression model in which the error structure is arbitrary, except for equality of its marginal distributions. Two simple but inefficient approaches to analysis are (i) to work with the differences between the two components of each response and (ii) to derive working independence estimators as if the two component responses were independent. The former strategy does well if the explanatory variables are balanced over pairs and the correlation between the two components of the response is high; the latter strategy does well when the response correlation is low or the covariates are highly unbalanced. We show that combining the two estimators can give a procedure with high efficiency in all situations. We show that an adjusted marginal score can be calculated that is uncorrelated with the within-pair score, so that separate intrapair and interpair estimators can be calculated. For bivariate normal regression models our approach is identical to the usual procedure for combining intra- and interblock information. In general the approaches are not the same. Detailed calculations and a numerical example are given for a bivariate extreme value model due to Gumbel that is also important in survival analysis. Extensions from bivariate to general multivariate responses are indicated.

Background: Vancomycin resistance among enterococci is an emerging nosocomial problem. Consequently, it is important to understand the distri-bution of vancomycin-resistant enterococci (VRE) within and between hospitals to implement appropriate infection control measures. Methods: In this study, 116 VRE isolates obtained from patients in 6 New York State hospitals were analyzed by antibiotic susceptibility testing, pulsed-field gel electrophoresis (PFGE) fingerprinting, plasmid profile analysis, vanA and vanB polymerase chain reaction, and DNA:DNA hybridization with vanA and vanB probes. Results: PFGE and plasmid typing generally agreed, but plasmid profiles were more variable. These analyses revealed that genetic heterogeneity among isolates from within each of the 6 hospitals varied considerably. Among 23 Enterococcus faecium isolates from one hospital, there were only 3 PFGE types, and 20 isolates had the same type. However, in another hospital, each isolate was genetically distinct. Closely related strains were not found in separate hospitals. VRE strains with vanA genes and strains with vanB genes were found in 3 hospitals. Both plasmid and chromosomal carriage of these genes was detected. Conclusions: PFGE typing showed that nosocomial VRE transmission had occurred in some hospitals. However, there was no evidence for it in others. Neither was there evidence for intrahospital transmission or for emergence of an endemic strain. These observations demonstrate that it is important to evaluate genetic heterogeneity among VRE before implementation of infection control measures. PFGE is the method of choice for epidemiologic typing, but polymerase chain reaction, plasmid, and hybridization studies can provide important information concerning the presence and potential for transfer of vancomycin resistance genes. (AJIC Am J Infect Control 1999;27:411-7)

One hundred ninety-five individual vancomycin-resistant Enterococcus faecium (VRE) isolates from five upstate New York hospitals were studied for antimicrobial susceptibilities to LY333328, quinupristin-dalfopristin, teicoplanin, ampicillin, and gentamicin. LY333328 was the most active antibiotic against VRE. The effect of media and methods on the antibacterial activity of LY333328, its synergy with ampicillin, and the postantibiotic effects (PAE) of LY333328 and ampicillin were evaluated. In microdilution tests, the MIC of LY333328 at which 90% of the isolates were inhibited (MIC 90 ) was 2 μg/ml in Mueller-Hinton II (MH II) broth and 1 μg/ml in brain heart infusion (BHI) broth. In contrast, on MH II agar the MIC 90 was 4 μg/ml and on BHI agar it was >16 μg/ml. Bactericidal activity was observed for most strains at concentrations from 8 to ≥133 times the MIC of the tube macrodilution in MH II broth. A bactericidal effect of LY333328 plus ampicillin was demonstrated in time-kill studies, but there was great strain-to-strain variability. By the MH II agar dilution method, bacteristatic synergy (defined as a fractional inhibitory concentration of

Hematopoietic growth factors allow dose escalation of chemotherapy. This approach may potentially reduce the quality and quantity of hematopoietic stem cells. The capacity of stem cells recovered after dose intensification to support myeloablative therapy is unknown. In patients with previously untreated advanced follicular lymphoma, trilineage hematopoietic engraftment was compared in two sequential trials of induction therapy (standard dose cyclophosphamide, doxorubicin, vincristine, prednisone [CHOP] without growth factors or dose intensification CHOP supported by granulocyte colony-stimulating factor [G-CSF ]) followed by identical myeloablative therapy and autologous stem cell support. Neutrophil, platelet, and red blood cell (RBC) engraftment were compared on days 100, 180, and 360 after stem cell reinfusion. Despite similar patient characteristics including reinfusion of comparable numbers of marrow mononuclear cells, after stem cell transplantation, a highly significant prolongation of neutrophil and platelet engraftment was seen in patients who received high dose CHOP and G-CSF in comparison to standard dose CHOP. These findings suggest that dose intensified chemotherapy and G-CSF recruited stem cells into a proliferative phase and that G-CSF allowed retreatment at a time when stem cells were susceptible to damage by cytotoxic therapy. Such inadequate hematologic engraftment after myeloablative therapy might be avoided by either shortening the time that growth factor support is administered, lengthening the interval between cycles, or attempting to repetitively harvest additional stem cells either from the marrow or peripheral blood. Therefore, intensification of chemotherapy with growth factor support must be used with caution if stem cells are to be used to support myeloablative therapy.

The proliferative capacity of T cells infiltrating human tumors is known to be impaired, possibly through their interaction with tumor. Here we demonstrate that soluble products derived from renal cell carcinoma (RCC-S) explants but not normal kidney can inhibit an IL-2-dependent signaling pathway that is critical to T cell proliferation. A major target of the immunosuppression was the IL-2R-associated protein tyrosine kinase, Janus kinase 3 (Jak3). RCC-S suppressed basal expression of Jak3 and its increase following stimulation with anti-CD3/IL-2. Jak3 was most sensitive to suppression by RCC-S; however, reduction in expression of p56(lck), p59(fyn), and ZAP-70 was observed in some experiments. Expression of other signaling elements linked to the IL-2R (Jak1) and the TCR (TCR-zeta, CD3-epsilon, and phospholipase C-gamma) were minimally affected. In naive T cells, RCC-S also partially blocked induction of IL-2R alpha-, beta- and gamma-chain expression when stimulating via the TCR/CD3 complex with anti-CD3 Ab. To determine whether RCC-S suppressed IL-2-dependent signaling, primed T cells were employed since RCC-S had no effect on IL-2R expression but did down-regulate Jak3 expression and, to a lesser degree, p56(lck) and p59(fyn). Reduction in Jak3 correlated with impaired IL-2-dependent proliferation and signal transduction. This included loss of Jak1 kinase tyrosine phosphorylation and no induction of the proto-oncogene, c-Myc. These findings suggest that soluble products from tumors may suppress T cell proliferation through a mechanism that involves down-regulation of Jak3 expression and inhibition of IL-2-dependent signaling pathways.

CD94 (Kp43) is a member of the human C-type lectin superfamily encoding type II membrane glycoproteins expressed on NK cells and a subset of T cells. Ligation of CD94 has been shown to either potentiate or inhibit NK cell proliferation and cytolytic effector function. Here we show that CD94 ligation triggers apoptosis in IL-2-primed NK cells. Evidence for CD94-induced apoptosis includes: 1) chromatin condensation as measured by increased fluorescence of Hoechst dye, 2) induction of DNA fragmentation, and 3) characteristic morphology by transmission electron microscopy. IL-2 priming (at least 12 h) is required for activation-induced NK cell death triggered by CD94. Activation-induced NK cell death triggered by CD94 ligation is extremely rapid (DNA fragmentation is first observed at 120 min). Unlike activation-induced T cell death, it is not inhibited by neutralizing Abs reactive with TNF-alpha or Fas ligand. Our results suggest that CD94 may play a role in the elimination of activated NK cells during the transition from the innate to the Ag-specific immune response.

Polymerase chain reaction-based screening of childhood acute lymphoblastic leukemia (ALL) samples showed that a TEL/AML1 fusion transcript was detected in 27% of all cases, representing the most common known gene rearrangement in childhood cancer. The TEL/AML1 fusion results from a t(12;21)(p13;q22) chromosomal translocation, but was undetectable at the routine cytogenetic level. TEL/AML1-positive patients had exclusively B-lineage ALL, and most patients were between the ages of 2 and 9 years at diagnosis. Only 3/89 (3.4%) adult ALL patients were TEL/AML1-positive. Most importantly, TEL/AML1-positive children had a significantly lower rate of relapse compared with TEL/AML1-negative patients (0/22 v 16/54, P = .004). Co- immunoprecipitation experiments demonstrated that TEL/AML-1 formed homodimers in vitro, and heterodimerized with the normal TEL protein when the two proteins were expressed together. The elucidation of the precise mechanism of transformation by TEL/AML1 and the role of TEL/AML1 testing in the treatment of childhood ALL will require additional studies.

IL-12 stimulates both T and NK cells and is pivotal in the development of the Th1 immune response. In this work, we show that an interaction between CD2 and CD58 on activated T cells and monocytes, respectively, regulates the T cell response to IL-12. B cells provide little IL-12-specific costimulation, and this correlates with the low level of CD58 on B cells relative to monocytes and the lack of significant up-regulation in response to IFN-gamma or PHA activation. CHO cell transfectants expressing CD58 at a level comparable with that found on monocytes restore IL-12 responsiveness to APC-depleted T cells. This effect is not observed with CHO cells expressing CD48, a second CD2 ligand with a low avidity for CD2 relative to CD58. Thus, in addition to augmenting adhesion between T cells and their cognate APCs and facilitating TCR-triggered activation, the CD2-CD58 interaction uniquely optimizes the T cell response to IL-12.

Study objective: To identify the oncology patient population presenting to the emergency department and examine the causes and clinical management of oncology symptoms in the ED. Design: Retrospective review of 5,640 adult patients, with the following variables identified for oncology patients presenting to the ED: age, sex, cancer type, cancer stage, previous cancer treatment, previous hospitalization, presenting symptoms, treatment provided in the ED, admission and discharge data, and day, time, and length of ED visit. Setting: Community teaching hospital with annual ED census of 31,000. Participants: All adult oncology patients who presented to the ED during the study period. We identified these patients by cross-referencing ED logs and tumor registry records. Results: Cancer history was identified for 284 of the 5,640 adult ED admissions (5%). Forty-three percent (n=122) of the 284 patients with cancer history had an oncology-related ED visit. The most common symptoms of these patients were gastrointestinal (48%), pain (40%), neurologic (38%), cardiac (25%), and pulmonary (23%). Ten percent of patients with oncology-related ED visits died during the admission, and 48% died within 1 year of the ED visit. Conclusion: Oncology patients present to the ED with symptoms of undiagnosed malignancy, complications of cancer treatment, and acute disease-related symptoms. Knowledge of an individual's cancer history and ability to recognize oncologic symptoms are important to the management of oncology patients. [Swenson KK, Rose MA, Ritz L, Murray CL, Adlis SA: Recognition and evaluation of oncology-related symptoms in the emergency department. Ann Emerg Med July 1995;26:12-17.]

In systemic candidiasis, endogenously produced tumor necrosis factor (TNF)-alpha prolongs survival of the infected host. To determine whether endogenously produced TNF-alpha has a beneficial effect beyond that provided by antifungal therapy, survival was assessed in infected mice that received fluconazole or amphotericin B alone and in combination with anti-TNF-alpha antibody. Neutralization of serum TNF-alpha did not affect survival in fluconazole recipients; however, for amphotericin B recipients, it significantly shortened mean survival. For both fluconazole and amphotericin B recipients, colony counts in organs were significantly higher in animals that also received anti-TNF-alpha antibody. Administration of anti-TNF-alpha antibody with amphotericin B or fluconazole did not affect the morphology of fungi or the inflammatory response in kidneys. This study suggests that exogenous TNF-alpha and drugs that increase the endogenous production of TNF-alpha by the host may be useful adjuncts to fluconazole and amphotericin B for the treatment of systemic candidiasis.

In certain polymeric solids - such as spin crossover (SCO) solids, and in allosteric assemblies - such as the rigor-state multi-sarcomere assembly, the lattice as a whole may exist in one of two alternative structural states. The elementary unit (protomer) in these two lattice states will differ in shape and/or size. In general, it will be present in a smaller size in one of the lattice states and in a larger size in the other. In recent kinetic studies in polymeric SCO solids, sigmoid-shaped relaxation curves were found, and this shape was regarded as a signature of cooperativity. In our kinetic studies in the allosteric multi-sarcomere assembly, we have also observed sigmoid-shaped relaxation curves.Here we address the origin of cooperativity in both types of system - polymeric and allosteric. The relaxation experiment on SCO solids begins with photoexcitation of the lattice into a metastable all-large-size state. This metastable lattice is then allowed to relax back to its stable all-small-size state. As individual small-size units begin to appear within the otherwise large-size lattice, they will distort their neighboring large-size units because they will not fit. The misfit-induced distortion of these units will, in turn, reduce the height of their activation barrier - and will thus increase their relaxation rate constant. This rate constant increase represents a self-acceleration effect and is a type of positive feedback. We conclude that positive feedback may play a fundamental role in the origin of cooperative relaxation - both in polymeric SCO solids as well as in an allosteric multi-sarcomere assembly.

Previous studies have shown that tumor-specific bcr-abl mRNA can often be detected by polymerase chain reaction. (PCR) for months to years after allogeneic bone marrow transplantation (BMT) for chronic myelocytic leukemia (CML). Nevertheless, the presence of bcr-abl mRNA by itself does not invariably predict for clinical relapse post-BMT. This has led to the hypothesis that bcr-abl mRNA might be expressed in cells that have lost either proliferative or myeloid differentiation potential. To directly characterize the cells detected by PCR in patients with CML after allogeneic BMT, we first identified five individuals in whom PCR-positive cells could be detected at multiple times post-BMT. Bone marrow samples from these individuals were cultured in vitro and single erythroid, granulocytic, and macrophage colonies, each containing 50 to 100 cells, were examined for the presence of bcr-abl mRNA by PCR. PCR-positive myeloid colonies could be detected in four of five individuals in marrow samples obtained 5 to 56 months post-BMT. Overall, 7 of 135 progenitor cell colonies (5.2%) were found to be PCR-positive. The expression of bcr-abl mRNA appeared to be equally distributed among committed erythroid, macrophage, and granulocyte progenitors. These patients have now been followed-up for an additional 20 to 33 months from the time of progenitor cell PCR analysis but only one of these individuals has been found to have cytogenetic evidence of recurrent Ph+ cells. These results show that long-term persistence of PCR-detectable bcr-abl mRNA after allogeneic BMT can be caused by the persistence of CML-derived clonogenic myeloid precursors that have survived the BMT preparative regimen. These cells continue to have both proliferative and myeloid differentiation capacity in vitro. Nevertheless, these PCR-positive cells do not appear to either expand or differentiate in vivo for prolonged periods, suggesting the presence of mechanisms for suppression of residual clonogenic leukemia cells in vivo.

The role of tumor necrosis factor alpha (TNF-alpha) in host defense against systemic Candida albicans infection was evaluated in a murine model of systemic candidiasis in which uniform death occurred between 5 and 6 days after infection. TNF-alpha was first detected at 16 h postinfection and progressively increased thereafter. Peak levels (700 to 900 pg/ml) were measured in mice near death. Administration of 0.5 to 1.0 mg of polyclonal immunoglobulin G (IgG) TNF-alpha antibody (TNF-alpha Ab) to mice 2 h preinfection neutralized serum TNF-alpha for up to 30 h. However, this regimen shortened survival from a mean of 5.5 days for IgG controls to 3.4 days (P = 1.9 x 10(-12)). Semiquantitative cultures of spleen, lung, liver, and kidney conducted at 1, 2, and 3 days postinfection found colony counts of spleen and kidney to be significantly higher for TNF-alpha Ab recipients but only for the first 48 h. Administration of 1.5 and 1.0 mg of TNF-alpha Ab at 2 h before and 48 h after fungal injection, respectively, shortened the mean survival from 4.9 to 2.3 days (P = 5.2 x 10(-8)). This regimen neutralized serum TNF-alpha throughout infection. With this regimen, colony counts of all organs were significantly higher in TNF-alpha Ab recipients at 1, 2, and 3 days postinfection. Histopathologic studies showed an increase in the number and size of C. albicans foci in tissues. Peripheral leukocyte counts and inflammatory response in tissue were similar for TNF-alpha Ab and IgG sham recipients. In vitro, incubation of C. albicans with four to eight times the peak serum levels of TNF-alpha for up to 24 h did not inhibit the rate of germ tube or pseudohypha formation. Thus, TNF-alpha that was produced during infection with C. albicans augmented host resistance against this organism and prolonged survival. The protective effect of TNF-alpha was not mediated by increased leukocytes in blood or tissues nor by a direct anticandidal effect of TNF-alpha. This study suggests that the administration of exogenous TNF-alpha may enhance host resistance against systemic C. albicans infection and may improve host survival.

The activities of FK037, cefpirome, ceftazidime and cefepime against 71 aminoglycoside-resistant, 35 aminoglycoside-sensitive, 29 cystic fibrosis Pseudomonas aeruginosa isolates, and 31 Pseudomonas spp. strains were studied using the agar dilution technique (final inoculum 10(4) c.f.u./spot). The MIC90 for aminoglycoside-sensitive P. aeruginosa against FK037, cefpirome, ceftazidime and cefepime was 32, 16, 8 and 16 mg/l, respectively. The MIC90 for P. aeruginosa strains resistant to one or more aminoglycosides was similar for FK037, cefpirome and ceftazidime (128 mg/l) and two dilutions lower for cefepime (32 mg/l). The MIC90 for P. aeruginosa isolates highly resistant to all three aminoglycosides (MIC > or = 128 mg/l) was 64 mg/l for FK037 and cefpirome, and 32 mg/l for ceftazidime and cefepime. The MIC90 for P. aeruginosa from patients with cystic fibrosis was 32 mg/l for all four cephalosporins tested, and 8, 32 and 64 for tobramycin, gentamicin and amikacin, respectively. Xanthomonas maltophilia was resistant to all four cephalosporins and three aminoglycosides. The activity of ceftazidime and cefepime was one to two dilutions greater against P. cepacia and P. picketti than of FK037 and cefpirome. The activity of ceftazidime was two dilutions greater than the other three cephalosporins against P. fluorescens. In kinetic time kill curves against P. aeruginosa, all four cephalosporins demonstrated similar activity at 6 and 24 h when tested at 1 x MIC. At 2 x MIC, regrowth was less at 24 h for cefepime, cefpirome and FK037 than for ceftazidime. In time kill curves for P. aeruginosa, synergy was clearly demonstrated at 1/4 MIC and 1/2 MIC concentrations for FK037 and tobramycin.

Candida glabrata causes infections associated with severe sepsis, production of high concentrations of cytokines/chemokines, and high mortality. This study describes the effects of anidulafungin (ANF) and voriconazole (VRC), singly and in combination, on the production of eight cytokines/chemokines by human monocyte-derived macrophages (MDM) infected with C. glabrata or activated by lipopolysaccharide (LPS).MDM monolayers were established, infected with C. glabrata or activated with LPS, and then treated with high or low concentrations of ANF, VRC, or both. Cytokine/chemokine levels in MDM supernatants were determined.Levels of cytokines/chemokines were significantly elevated in supernatants of infected or LPS-activated MDM. Except for interleukin-10, all significant decreases in cytokine/chemokine concentrations (p0.01) occurred in supernatants of infected MDM treated with high concentrations of ANF or ANF + VRC.Decreases in cytokine/chemokine levels in supernatants of infected MDM treated with high concentrations of ANF or ANF + VRC suggest that similar treatment could improve survival in patients with severe, invasive C. glabrata infections and markedly elevated levels of serum cytokines/chemokines.

Candida glabrata (Cgl) and Candida parapsilosis (Cpa) can cause serious infections and can be resistant to some antifungal drugs. In treating infections caused by these organisms, killing rates and post-antifungal effects (PAFE) are important factors in both dose interval choice and outcome. Two strains each of Cgl and Cpa were studied. For PAFE studies, each organism was exposed to micafungin (MCF), anidulafungin (ANF), or caspofungin (CAS) for 1 h at concentrations ranging from 0.25 to 16×MIC. Cell suspensions were then washed 3 times and resuspended in fresh broth. Time 0 was immediately after resuspension of the yeast. Time-kill experiments were done using similar drug concentrations. Samples were removed at each time point (0-120 h) and viable counts determined. PAFE of ANF and CAS were generally very long, were markedly longer than those of MCF, and increased with increased drug concentration. For ANF and CAS, PAFE for Cgl were greater than those for Cpa only at 0.5 to 2 × MIC. Time-kill experiments showed that ANF, CAS, and MCF were fungicidal at 8 to 16 × MIC up to 120 h. CAS had the greatest activity against Cgl, while ANF and MCF were more active than CAS against Cpa. Because of the prolonged PAFE of these echinocandins, especially ANF and CAS, less frequent dosing during therapy of Cpa and Cgl infections could be considered. Further studies are needed to determine the clinical efficacy of longer dosing intervals.