Escherichia coli levels and microbial source tracking in stormwater retention ponds and detention basins

Little is known about the spatial and temporal changes that occur with Escherichia coli in urban stormwater systems. The goal of this project was to assess E. coli in urban stormwater detention basins and retention ponds, not connected to the sewer system, to determine temporal and spatial differences and evaluate the sources of E. coli utilizing microbial source tracking (MST). Surface water quality was sampled at three detention basins and five retention ponds during major storm events in the summers of 2018 and 2019. One week after each storm, groundwater and surface water were sampled. The MST samples were taken from storm events and normal flows, for both surface and groundwater. E. coli levels were higher during rain events in both detention basins and retention ponds and infrequently met a recreational standard. E. coli in groundwater was pervasive and infrequently met a recreational standard. The MST analysis found sewage, dog, human, and bird markers during storm events and sewage and bird markers during regular flows. PRACTITIONER POINTS: Rain events had significantly more E. coli than during normal flows in both retention ponds and detention basins. E. coli in groundwater was ubiquitous and fluctuates over time. Microbial source tracking (MST) found bird, dog, human, and sewage markers present during all storm events analyzed.

Abstract P1-09-08: BCL2L1 (BCL-XL) expression and MYC super-enhancer positivity predict sensitivity to the covalent CDK7 inhibitor SY-1365 in triple negative breast cancer (TNBC) cell lines

Effective therapies for TNBC remain elusive. As such, TNBCs are associated with a high risk of relapse and short progression free- and overall-survival. Recent studies showed that TNBC cells are highly dependent on the transcriptional regulator CDK7, and suggest that the mitochondrial apoptosis pathway is important in mediating cell survival in CDK7-dependent cells. Further, TNBC has been shown to have a distinct epigenetic and transcriptional program, with super-enhancers (SE) mediating the expression of key oncogenic drivers such as MYC. SY-1365, a covalent and selective inhibitor of CDK7, was developed to exploit dysregulated programs thought to drive SE-mediated transcriptional-dependencies in TNBC and other cancers. To identify potential biomarkers predictive of sensitivity to SY-1365, we evaluated SY-1365 inhibitory activity in a large panel of human tumor cell lines, including TNBC lines, and correlated sensitivity with RNA expression and epigenetic profiles.

SY-1365 dose-response curves were measured using the ATP-lite assay in a panel of 406 human tumor cell lines, including 19 TNBC cell lines. Clustering of growth-rate adjusted dose response curves of cell-lines treated with SY-1365 allowed the classification of cell-lines into low and high response groups. An unbiased genome wide approach was used to compare response classification to RNA expression data across all cell lines to identify gene expression markers predictive of sensitivity to SY-1365. Furthermore, a hypothesis driven approach was followed to interrogate whether the MYC SE predicted sensitivity to SY-1365.

Twenty-five genes were differentially expressed between SY-1365-sensitive and -insensitive tumor lines (FDR<0.05). Lower expression of BCL2L1, which encodes the mitochondrial apoptosis regulator BCL-XL, was identified as the most predictive expression biomarker of sensitivity across all profiled cell lines, strongly separating the two classes of sensitivity (Accuracy=70%, FDR<0.005). Further, this predictive power of lower BCL2L1 expression was maintained in an analysis restricted to the subset of TNBC cell-lines (Accuracy=73%).

Expanding beyond expression analysis, we also found that the strength of the MYC SE (as defined by H3K27Ac) was predictive of response to SY-1365 in TNBC (Accuracy=86%, FDR<0.05).

In this study, we show for the first time that SY-1365 induced differential responses across a large panel of human tumor cell lines derived from multiple indications. We also show that in this panel of cell lines the response could be predicted in an “indication agnostic” manner by the level of expression of BCL2L1. Finally, in line with prior reports, in TNBC cell lines, MYC SE was significantly associated with sensitivity to SY-1365. These observations have generated strong hypotheses for selection strategies aimed at identifying patients with tumors particularly sensitive to CDK7 inhibition with SY-1365, and warrant further investigation with respect to predictive biomarkers of response in patients. SY-1365 is currently being assessed in a phase 1 trial in adult patients with advanced solid tumors, including a planned expansion cohort enriching for patients with TNBC (NCT03134638).

Citation Format: Rajagopal N, Hodgson G, Hu S, McKeown M, Bush A, Fritz C, Orlando D, Olson E, di Tomaso E. BCL2L1 (BCL-XL) expression and MYC super-enhancer positivity predict sensitivity to the covalent CDK7 inhibitor SY-1365 in triple negative breast cancer (TNBC) cell lines [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-09-08.

Abstract P5-18-03: Clinicopathological features among patients with HER2-positive breast cancer with prolonged response to trastuzumab based therapy

Background: HER2-positivity is a predictor of benefit from trastuzumab (TRZ), but fails to depict the observed interpatient variability in terms of treatment (tx) duration. In this study we described the relationship between clinicopathological features and TRZ tx duration.

Methods: A retrospective consecutive series of 343 HER2+ breast cancer (BC) patients (pts) treated with TRZ at the Dana-Farber Cancer Institute from 1999–2008 was identified. 139 pts treated with 1st line TRZ-based tx were selected for analysis. Pts who received any non-TRZ prior tx for metastatic disease were excluded. TRZ tx duration was defined as time from start of 1st line therapy to the 1st day of 2nd line therapy or death. Central nervous system (CNS) progression with TRZ maintenance was not considered change of tx. Pts were divided equally into 3 groups based on the duration of 1st line tx distribution. Short-term responders (STR) were on the 1st line tx for <7 months (m), intermediate responders (IR) 7–15m and long responders (LTR) for >15m. An additional group of extremely LTR (ELTR) was defined as being in the 90th percentile of tx duration (>37m). Descriptive analysis was performed; fisher exact test, Kruskal-Wallis and logistic regression methods were used to compare groups.

Results: Median follow-up time since metastatic diagnosis was 4 years (y) (range 0–11). Median age at diagnosis was 47y (22–83), 25% of stage I-III pts at diagnosis received adjuvant/neoadjuvant TRZ. The median disease free interval (DFI) was 20m (0–172), median number of metastatic sites was 2(1–5), 68% of pts had visceral disease. Median duration of 1st line tx was 10m (2–105). TRZ was given with CT in 86%, hormone tx in 6% and as monotherapy in 9%. 25% of pts developed CNS progression and continued tx. There were only small absolute differences for clinicopathological characteristics among STR, IR and LTR.

Prostate-cancer (CaP) screening decision aid for black men designed to enhance shared decision-making

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Background: The high CaP incidence and mortality of black men combined with their relatively low rate of CaP screening and their elevated risk of presenting with advanced disease has led to their being identified as a high-priority group for screening. The benefit of screening, however, is uncertain. Most guidelines recommend that men make an individualized screening decision in consultation with their doctor. Motivating and preparing men to actively participate in this difficult decision remains a challenge. This is particularly relevant regarding black Americans given their historical alienation from the health care system. Methods: A CaP screening decision aid designed to promote shared decision-making was tested in 5 small group sessions of black men at community sites in Boston. The decision aid was preceded by a brief didactic presentation on CaP screening. The decision aid included a graphical depiction of all potential major outcomes that may follow a decision for or against screening. Vignettes about the decision-making and outcomes of hypothetical men with different life circumstances and priorities were presented to enhance values clarification by the participants. Endpoints measured before and after the intervention included self efficacy (SE)[Decision Self Efficacy Scale], decisional conflict (DC) [Decisional Conflict Scale], desire for autonomy (DFA) [Control Preferences Scale], and prostate cancer knowledge (PCK) [Prostate Cancer Knowledge and Prostate Cancer Screening Knowledge scales]. Pre- and post-intervention scores were compared using a Wilcoxon Matched-Pairs Signed Rank test. Results: 64 men were accrued over 4 months during 2005. Significant changes were seen in all measures. Average scores improved 16% on SE (p<.001) and 17% on DC (p<.004). DFA increased, with the proportion of men wanting to play a dominant role in health care decisions rising from 62% to 81% (p<.001). PCK more than doubled on both scales (p<.001). Focus groups held after the intervention reinforced these findings. Conclusions: Men were better informed, felt better prepared to actively participate in CaP screening decisions, and wanted to play a stronger role in decisions about their health care following exposure to our decision aid.

No significant financial relationships to disclose.

Transplantation of unrelated placental blood cells in children with high-risk sickle cell disease

The lack of healthy HLA-identical sibs limits the use of allogeneic hematopoietic cell transplantation in children with high-risk sickle cell disease (SCD). We evaluated unrelated placental blood cell transplantation (UPBCT) after a preparative regimen of busulfan, cyclophosphamide and antithymocyte globulin in three children with SCD who had cerebrovascular accidents (CVAs) and did not have HLA-matched sib donors. The placental blood cell units were matched with the recipients at four of six HLA-A, HLA-B and HLA-DRB1 antigens. Neutrophil levels above 0.5 x 10(9)/l occurred at 23, 38 and 42 days after UPBCT, and platelet levels above 50 x 10(9)/l without transfusions occurred at 62, 81 and 121 days after UPBCT. All patients developed acute graft-versus-host disease (GVHD; two grade II, one grade III), and one developed extensive chronic GVHD. One patient had graft failure and autologous hematopoietic recovery. Two patients have complete donor hematopoietic chimerism without detectable hemoglobin S or symptoms of SCD at 40 and 61 months, respectively, after UPBCT. These observations demonstrate the feasibility of UPBCT in children with SCD. Further studies of UPBCT for SCD are needed but, because of risks of procedure-related morbidity and graft rejection, should be restricted to pediatric patients with high-risk manifestations of SCD.

Biogeography and ecological setting of Indian Ocean hydrothermal vents

Within the endemic invertebrate faunas of hydrothermal vents, five biogeographic provinces are recognized. Invertebrates at two Indian Ocean vent fields (Kairei and Edmond) belong to a sixth province, despite ecological settings and invertebrate-bacterial symbioses similar to those of both western Pacific and Atlantic vents. Most organisms found at these Indian Ocean vent fields have evolutionary affinities with western Pacific vent faunas, but a shrimp that ecologically dominates Indian Ocean vents closely resembles its Mid-Atlantic counterpart. These findings contribute to a global assessment of the biogeography of chemosynthetic faunas and indicate that the Indian Ocean vent community follows asymmetric assembly rules biased toward Pacific evolutionary alliances.

Temporal and spatial overlap between monarch larvae and corn pollen

To assess the likelihood that monarch larvae will be exposed to Bacillus thuringiensis (Bt) pollen, we studied milkweed and monarch densities in habitats which comprise much of the land available to breeding monarchs, e.g., cornfields, cornfield edges, other agricultural fields, and nonagricultural areas, in four regions of the monarch breeding range. We found that monarchs use milkweed in cornfields throughout their breeding season, and that per plant densities are as high or higher in agricultural habitats as in nonagricultural habitats. As a result of the prevalence of agricultural land, most of the monarchs produced in the upper Midwest are likely to originate in cornfields or other agricultural habitats. There was a greater temporal overlap between susceptible monarchs and corn anthesis in the northern than the southern part of the summer breeding range, because of earlier pollen shed in the south. The importance of agricultural habitats to monarch production suggests that, regardless of the impact of genetically modified crops, agricultural practices such as weed control and foliar insecticide use could have large impacts on monarch populations.

Surrogate decision makers' attitudes towards tube feeding in the nursing home

In the nursing home, a widely accepted medical practice is to recommend the initiation of long term tube feeding in residents with eating difficulties. However, frequently the nursing home resident has dementia, lacks decision-making capacity, and has no advance directives to guide the physician and the family member(s). Therefore, the family member or another surrogate decision maker has to make the difficult decision of whether or not to consent to the placement of a feeding tube. We surveyed 50 English speaking surrogates of nursing home residents who were on a feeding tube for at least 6 months. Each surrogate was contacted by telephone and was administered a 16-item structured questionnaire. Statistical analyses included frequency distributions, and the Wilcoxon signed rank test for two related samples. Most surrogates rated the residents' quality of life as poor or extremely poor. Yet, 78% of the surrogates perceived tube feeding to be beneficial, 62% would repeat their initial decision to initiate tube feeding, and 68% would not consider removal of the feeding tube. Their leading concerns were medical complications, tube feeding's impact on each resident's quality of life, and adequacy of nursing care. The surrogates were satisfied with their initial decision for the placement of a feeding tube despite their perception that there was no improvement in the quality of life of the residents. The surrogates may have viewed tube feeding as a life prolonging measure.

Drinking water contaminants and childhood leukemia

We conducted a population-based case-control study to evaluate the relation between exposure to drinking water contaminants (total and specific trihalomethanes and certain metals and nitrates) and childhood acute lymphoblastic leukemia. We compared 491 cases 0-9 years of age with 491 controls. We developed a municipality-exposure matrix based on municipal and provincial historical data, a tapwater survey in 227 homes, and information about residential history. We used average level of exposure and cumulative average over the period as exposure indices, and we measured risk for the pregnancy period as well as for the postnatal period. We show that risks were generally not increased for the prenatal period nor with average levels of exposure. Postnatal cumulative exposure for total trihalomethanes at above the 95th percentile of the distribution for cases and controls was associated with an odds ratio of 1.54 (95% confidence interval = 0.78-3.03); for that same period, risk associated with exposure to chloroform was increased (odds ratio = 1.63; 95% confidence interval = 0.84-3.19) as well as that for exposure to zinc (odds ratio = 2.48; 95% confidence interval = 0.99-6.24). Risks were also increased for exposure to cadmium and arsenic, but not for other metals nor for nitrates.

Markers of infection, breast-feeding and childhood acute lymphoblastic leukaemia

Infections are suspected to play a role in the aetiology of childhood leukaemia. In 1989-95, we evaluated the relation between childhood acute lymphoblastic leukaemia and pre- and postnatal markers of exposure to infection, as well as breast-feeding. A population-based case-control study was carried out in certain regions of Québec, Canada, in 1989-95 including 491 incident cases diagnosed between 1980 and 1993 and aged between 0 and 9 years. An identical number of healthy controls matched for age, sex and region of residence at the date of diagnosis was included. Having older siblings, mother's use of antibiotics during pregnancy, and being born second or later were all associated with increased risk of leukaemia while early day-care attendance (odds ratio (OR) = 0.49; 95% CI 0.31-0.77), and breast-feeding (OR = 0.68; 95% CI 0.49-0.95) were significantly protective. A marker of population mixing was not a risk factor. When including all variables defining family structure in a model, having older siblings at time of diagnosis was a risk factor among children diagnosed before 4 years of age (OR = 4.54; 95% CI 2.27-9.07) whereas having older siblings in the first year of life was protective among children diagnosed at 4 years of age or later (OR = 0.46; 95% CI 0.22-0.97).

MEF2: a transcriptional target for signaling pathways controlling skeletal muscle growth and differentiation

Skeletal muscle development involves a multistep pathway in which mesodermal precursor cells are selected, in response to inductive cues, to form myoblasts that later withdraw from the cell cycle and differentiate. The transcriptional circuitry controlling muscle differentiation is intimately linked to the cell cycle machinery, such that muscle differentiation genes do not become transcribed until myoblasts have exited the cell cycle. Members of the MyoD and MEF2 families of transcription factors associate combinatorially to control myoblast specification, differentiation and proliferation. Recent studies have revealed multiple signaling systems that stimulate and inhibit myogenesis by altering MEF2 phosphorylation and its association with other transcriptional cofactors.

Factors that increase the risk of leakage during surgical removal of benign cystic teratomas

The contents of mature cystic teratomas can be a potent irritant resulting in chemical peritonitis. Using a retrospective cohort, we examined the various risk factors for leakage of benign cystic teratomas during laparoscopy and laparotomy. Cyst leakage of the benign cystic teratoma contents was the primary endpoint. In all, 158 women underwent surgery for a total of 178 ovarian benign cystic teratomas. Statistical analysis was performed using chi(2), Mann-Whitney U and multivariate logistic regression analysis. A total of 115 benign cystic teratomas was successfully removed without intra-operative leakage and 63 underwent intra-operative leakage either at laparoscopy or laparotomy. The likelihood of success of removing the benign cystic teratoma intact was unrelated to age, pre-operative size or surgical technique. There was no difference among cystectomies performed by laparotomy in surgeon experience or the presence of adhesions. However, surgeons with more laparoscopic experience (>35 laparoscopies/year) were less likely to have intra-operative leakage (relative risk: 0.5, 95% confidence interval: 0.2, 1.2) compared to surgeons with less experience (<20/year) at cystectomy (26.1 versus 51.2% respectively). Oophorectomy significantly reduced the frequency of intra-operative leakage at both laparoscopy and laparotomy (14.7%). These findings suggest that laparoscopic experience can reduce the risk of leakage at cystectomy. At laparotomy, lack of surgeon postgraduate years of experience was not a risk factor for leakage.

Immunomagnetic recovery of human neutrophil defensins from the human gingival crevice

The human neutrophilic protein defensins are cationic, antimicrobial, cytotoxic, corticostatic chemotactic, opsonic peptides found in azurophilic granules and constitute about 5% of the total protein in human neutrophils. In the present study, defensins were recovered from the human gingival crevice using paramagnetic microspheres (beads), coated with anti-defensin antibodies. The bead-bound defensins were assayed using an enzyme-linked immunosorbent assay developed in this laboratory. Twenty sites were sampled; defensin was found in 100% of the sites and ranged in amount from 270-2000 ng/site. The large local concentrations of defensins, estimated in the mg/ml range, may have major effects on the microbiology of the gingival crevice.

Broad spectrum antimicrobial biocides target the FabI component of fatty acid synthesis

The broad spectrum antibacterial properties of 2-hydroxydiphenyl ethers have been appreciated for decades, and their use in consumer products is rapidly increasing. We identify the enoyl-acyl carrier protein reductase (fabI) component of the type II fatty acid synthase system as the specific cellular target for these antibacterials. Biologically active 2-hydroxydiphenyl ethers effectively inhibit fatty acid synthesis in vivo and FabI activity in vitro. Resistant mechanisms include up-regulation of fabI expression and spontaneously arising missense mutations in the fabI gene. These results contradict the view that these compounds directly disrupt membranes and suggest that their widespread use will select for resistant bacterial populations.

Sequential outbreak of influenza A and B in a nursing home: efficacy of vaccine and amantadine

OBJECTIVE

To describe the sequential occurrence of influenza A and B in a nursing home, and to determine the efficacy of influenza vaccine and/or amantadine treatment with respect to incidence and sequelae.

SETTING

The Jewish Home and Hospital for Aged, a skilled-care nursing facility.

PARTICIPANTS

Of 499 frail older nursing home residents, 139 contracted influenza during the study period (mean age 87.5 years; SD = 6.7). The residents were followed from February through April 1988.

INTERVENTION

Influenza vaccine and/or amantadine.

MEASUREMENTS

Episodes of influenza and their sequelae, i.e., pneumonia, hospitalization, and death.

RESULTS

The vaccine had no effect on the incidence of influenza-like illness, length of illness, or the associated death rate. It reduced the rate of pneumonia secondary to influenza A and B (relative risk = .57; 95% CI: .37 to .89; P = .023). Amantadine did not affect the attack rate of influenza nor the rate of pneumonia secondary to influenza. It was associated with decreased mortality (relative risk = 0; P = .001), and shorter length of influenza A illness (PWilcoxon = .082). Although the combination of amantadine and vaccine did not affect length of influenza (A or B) illness, it was associated with a significantly lower rate of sequelae (relative risk = .58; 95% CI: .36 to .95; P = .024).

CONCLUSION

In this epidemic, the combination of amantadine and vaccine was most effective in reducing the rate of influenza-associated sequelae. The possibility of a "biphasic" epidemic prompts consideration of vaccinating nonimmunized nursing home residents, even though it may be late in the influenza season.

Construction of human factor IX expression vectors in retroviral vector frames optimized for muscle cells

Development of a highly refined human factor IX (hFIX) expression vector system is critical for establishing a durable hemophilia B gene therapy. Here we report construction of a series of retroviral vectors and identification of an optimal basic structure and components for expressing hFIX in skeletal muscle cells. These vectors, which are derived from Moloney murine leukemia virus (MoMLV) with its enhancer sequence in the 3' long terminal repeat (LTR) deleted, contained internal hFIX expression units inserted in forward configuration without or with a viral vector intron sequence (pdL or pdLIn vector frame, respectively) or in inverted configuration without a viral vector intron sequence (pdLi frame). Internal expression units contained a hFIX cDNA or hFIX minigene (hIXm1 or hIXm2) derived from the hFIX cDNA by insertion of a shortened first intron sequence of the hFIX gene. Regardless of the promoter and vector frame used, both hIXm1 and hIXm2 gave 10- to 14-fold higher hFIX expression compared to those with hFIX cDNA. Internal hFIX transcriptional control units of these vectors were composed of various promoters linked with or without the muscle creatine kinase enhancer (Me) sequence. Promoters tested included those of alpha-actin (alpha A775), beta-actin (beta A280), cytochrome oxidase (CO1250 and CO650), myogenin (Mg1031 and Mg353), and Rous sarcoma virus (RSV). beta A200, which was derived from beta A280 by eliminating potential polyadenylation sites, was also tested. As extensively examined with the myogenin promoter, presence of one or multiple copies of Me in the vectors elevated the expression activity in myotubes by 4.5- to 19-fold over those without Me, but not significantly in myoblasts. Similar enhancements in expression activity with Me were also observed with other promoters, except those of RSV and CO. The latter two showed only modest enhancements in the presence of Me. As assayed with myotubes in culture, the general order of hFIX expression activity of various promoters with four copies of Me in the three different vector frames was beta A280 approximately beta A200 > Mg353 > Mg1031 approximately RSV approximately CO650 approximately alpha A775 > CO1250. One exception was that CO650 showed significantly less activity in pdLi-type vectors than in the pdLIn vectors. Based on the systematic analyses of various structural components, a group of pdLi vectors consisting of beta A200, two to four copies of Me, and hIXm2 was identified to have the optimal basic vector structure to be used in retrovirus for hFIX expression in differentiated skeletal muscle cells. The present studies provide the critical first step for establishing a highly refined hemophilia B gene therapy based on skeletal muscle-targeted hFIX gene transfer.

Identification of phosphorylation sites of human 85-kDa cytosolic phospholipase A2 expressed in insect cells and present in human monocytes

The phosphorylation sites on the human, 85-kDa cytosolic phospholipase A2 (cPLA2) were identified using recombinant cPLA2 expressed in Spodoptera frugiperda (Sf9) cells. Analysis by high performance liquid chromatography of tryptic digests of 32P-labeled recombinant cPLA2 showed four major peaks of radiolabeled phosphopeptides. The phosphorylated residues were identified as Ser-437, Ser-454, Ser-505, and Ser-727 using mass spectrometry and automated Edman sequencing. Sf9 cells infected with recombinant virus expressing cPLA2 exhibited a time-dependent release of arachidonic acid in response to the calcium ionophore A23187 or the protein phosphatase inhibitor okadaic acid, which was not observed in Sf9 cells infected with wild-type virus. Stimulation of Sf9 cells with A23187 and okadaic acid also increased the level of phosphorylation of cPLA2. Okadaic acid, but not A23187, induced a gel shift of cPLA2 and increased the level of phosphorylation of Ser-727 by 4.5-fold, whereas the level of phosphorylation of the other sites increased by 60% or less in response to both agonists. To determine whether the same sites on cPLA2 were phosphorylated in mammalian cells, human monocytes were studied. Okadaic acid stimulation of monocytes induced a gel shift of cPLA2, increased the release of arachidonic acid, and increased the level of phosphorylation of cPLA2 on serine residues. Comparison of two-dimensional peptide maps of tryptic digests of 32P-labeled recombinant cPLA2 and human monocyte cPLA2 demonstrated that the same peptides on cPLA2 were phosphorylated in mammalian cells as in insect cells. These results show that the Sf9-baculovirus expression system is useful for investigation of the phosphorylation sites on cPLA2. The results also suggest that phosphorylation of the cPLA2 by protein kinases other than mitogen-activated protein kinase may be important for the regulation of arachidonic acid release.

Allograft versus autograft anterior cruciate ligament reconstruction: 3- to 5-year outcome

Sixty-four patients whose knees underwent anterior cruciate ligament reconstruction with nonirradiated allograft tissue were compared with 26 patients whose anterior cruciate ligaments were reconstructed using autograft tissue 3 to 5 years after their operation. Detailed symptoms, activity-level, and functional outcomes, physical examination, and instrumented knee testing were recorded. No statistically significant differences were found except a higher incidence of loss of terminal extension in the autograft group. These differences were small and not considered clinically significant. Laxity and knee scores were similar in both groups. According to International Knee Documentation Committee ratings, overall outcome was normal or nearly normal in 48% of the allograft patients and in 38% of the autograft patients. Overall subjective rating with the Cincinnati Knee Score was 85.8 for the allograft patients and 84.5 for the autograft patients. Allograft tissue provides an acceptable alternative to autograft tissue for reconstruction of the anterior cruciate ligament.

Baseline (laser) eye examination program

Eye injury is the primary hazard associated with laser use. A baseline laser eye examination program allows for pre-injury examination and preventive early diagnosis of eye problems (glaucoma). Using portable equipment and a simplified exam format, and staffed by corpsmen and eye care providers, a rapid and accurate large-scale program that is cost efficient can be instituted. A single location for ophthalmic information coupled with recent refraction data will enhance readiness for deployment. For service members and their providers, a new and well-run eye care program will foster a strong and positive bond with the medical department.

Depressed adolescents with a history of sexual abuse: diagnostic comorbidity and suicidality

OBJECTIVE

To determine the nature of comorbid psychopathology and suicidality associated with a history of sexual abuse in depressed adolescents.

METHOD

Twenty-four depressed adolescent inpatients with a history of sexual abuse were compared with a matched control group of 24 depressed adolescent inpatients on measures of depression, suicidal ideation and behavior, and posttraumatic stress disorder (PTSD) symptoms.

RESULTS

Depressed adolescents with a history of sexual abuse had a higher prevalence of comorbid PTSD than did those without such a history. Chronicity and severity of abuse were significant contributors to a PTSD diagnosis. No differences were found in depression severity, specific depressive symptoms, or suicidal behavior.

CONCLUSION

Comorbidity of depressive disorders and PTSD are common among adolescent inpatients with a history of chronic sexual abuse. The need for thorough assessment of depression and PTSD with appropriate interventions for sexually abused adolescents is clear.

The inaccessibility of advance directives on transfer from ambulatory to acute care settings

OBJECTIVE

To investigate the accessibility of patients' previously executed advance directives during an acute hospitalization.

DESIGN

Retrospective chart review.

SETTING

A large metropolitan teaching hospital, a 514-bed skilled nursing facility, a geriatrics ambulatory care clinic, and a geriatrics group practice office.

PATIENTS

One hundred fourteen geriatric patients who had previously executed an advance directive.

MAIN OUTCOME MEASURES

The medical records of 180 admissions over 3 years, 1991 through 1993, were reviewed for documentation of patients' advance directive status.

RESULTS

Twenty-six percent of patients who had previously executed advance directives had their directives recognized during their hospitalization. Of the subgroup of patients who were judged not to have the capacity to make medical decisions during their admissions, 26% (14/53) had their directives recognized. When the advance directive was recognized, it appeared to influence treatment decisions in 12 (86%) of 14 cases.

CONCLUSIONS

Previously executed advance directives are not accessible when patients are admitted to hospitals for acute illness. When such directives are recognized, they are used to influence medical treatment decisions. Further research is needed to define and overcome barriers to this inaccessibility.

Spontaneous calcium transients regulate neuronal plasticity in developing neurons

Calcium ions play critical roles in neuronal differentiation. We have recorded transient, repeated elevations of calcium in embryonic Xenopus spinal neurons over periods of 1 h in vitro and in vivo, confocally imaging fluo 3-loaded cells at 5 s intervals. Calcium spikes and calcium waves are found both in neurons in culture and in the intact spinal cord. Spikes rise rapidly to approximately 400% of baseline fluorescence and have a double exponential decay, whereas waves rise slowly to approximately 200% of baseline fluorescence and decay slowly as well. Imaging of fura 2-loaded neurons indicates that intracellular calcium increases from 50 to 500 nM during spikes. Both spikes and waves are abolished by removal of extracellular calcium. Developmentally, the incidence and frequency of spikes decrease, whereas the incidence and frequency of waves are constant. Spikes are generated by spontaneous calcium-dependent action potentials and also utilize intracellular calcium stores. Waves are produced by a mechanism that does not involve classic voltage-dependent calcium channels. Spikes are required for expression of the transmitter GABA and for potassium channel modulation. Waves in growth cones are likely to regulate neurite extension. The results demonstrate the roles of a novel signaling system in regulating neuronal plasticity, that operates on a time scale 10(4) times slower than that of action potentials.

An ethics consult team in geriatric long-term care

The increasing incidence of ethical dilemmas in long-term care settings, in concert with recommendations from the President's Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research, has prompted long-term care institutions to develop mechanisms to address these concerns. Some facilities have chosen to set up an ethics committee, although estimates obtained in the past few years indicate that only between 2 and 27% of institutional long-term care settings have such committees. Ethics committees are responsible for assisting staff, residents, and families with the resolution of ethi- cal concerns, and typically engage in policy review and development, case review, and education. Such committees usually count among their membership representatives from a variety of disciplines, with family members, patients, and representatives from patient advocacy groups supplementing the professional component of the committee.

Ceramide structure predicts tumor ganglioside immunosuppressive activity

Molecular determinants of biological activity of gangliosides are generally believed to be carbohydrate in nature. However, our studies of immunomodulation by highly purified naturally occurring tumor gangliosides provide another perspective: while the immunosuppressive activity of gangliosides requires the intact molecule (both carbohydrate and ceramide moieties), ceramide structure strikingly influences ganglioside immunosuppressive activity. Molecular species of human neuroblastoma GD2 ganglioside in which the ceramide contains a shorter fatty acyl chain (C16:0, C18:0) were 6- to 10-fold more active than those with a longer fatty acyl chain (C22:0/C24:1, C24:0). These findings were confirmed in studies of ceramide species of human leukemia sialosylparagloboside and murine lymphoma GalNAcGM1b. Gangliosides that contain shorter-chain fatty acids (and are most immunosuppressive) are known to be preferentially shed by tumor cells. Therefore, the results suggest that the tumor cell is optimized to protect itself from host immune destruction by selective shedding of highly active ceramide species of gangliosides.

Action potentials, calcium transients and the control of differentiation of excitable cells

Calcium influx via action potentials in differentiating nerve and muscle is regulated principally by the expression of potassium currents. Transient elevations of intracellular calcium in spontaneously active cells are necessary for normal neuronal development. The mechanisms that connect calcium elevations to long term developmental change are likely to be utilized in the mature nervous system.