Cell-type-specific and disease-associated expression quantitative trait loci in the human lung

Common genetic variants confer substantial risk for chronic lung diseases, including pulmonary fibrosis. Defining the genetic control of gene expression in a cell-type-specific and context-dependent manner is critical for understanding the mechanisms through which genetic variation influences complex traits and disease pathobiology. To this end, we performed single-cell RNA sequencing of lung tissue from 66 individuals with pulmonary fibrosis and 48 unaffected donors. Using a pseudobulk approach, we mapped expression quantitative trait loci (eQTLs) across 38 cell types, observing both shared and cell-type-specific regulatory effects. Furthermore, we identified disease interaction eQTLs and demonstrated that this class of associations is more likely to be cell-type-specific and linked to cellular dysregulation in pulmonary fibrosis. Finally, we connected lung disease risk variants to their regulatory targets in disease-relevant cell types. These results indicate that cellular context determines the impact of genetic variation on gene expression and implicates context-specific eQTLs as key regulators of lung homeostasis and disease.

Expansion of endogenous T cells in CSF of pediatric CNS tumor patients undergoing locoregional delivery of IL13R〿2-targeting CAR T cells: an interim analysis

Outcomes for pediatric brain tumor patients remain poor, and there is optimism that chimeric antigen receptor (CAR) T cell therapy can improve prognosis. Here, we present interim results from the first six pediatric patients treated on an ongoing phase I clinical trial (NCT04510051) of IL13BBζ-CAR T cells delivered weekly into the lateral cerebral ventricles, identifying clonal expansion of endogenous CAR-negative CD8+ T cells in the cerebrospinal fluid (CSF) over time. Additionally, of the five patients evaluable for disease response, three experienced transient radiographic and/or clinical benefit not meeting protocol criteria for response. The first three patients received CAR T cells alone; later patients received lymphodepletion before the first infusion. There were no dose limiting toxicities (DLTs). Aside from expected cytopenias in patients receiving lymphodepletion, serious adverse events possibly attributed to CAR T cell infusion were limited to one episode of headache and one of liver enzyme elevation. One patient withdrew from treatment during the DLT period due to a Grade 3 catheter-related infection and was not evaluable for disease response, although this was not attributed to CAR T cell infusion. Importantly, scRNA- and scTCR-sequence analyses provided insights into CAR T cell interaction with the endogenous immune system. In particular, clonally expanded endogenous CAR- T cells were recovered from the CSF, but not the peripheral blood, of patients who received intraventricular IL13BBζ-CAR T cell therapy. Additionally, although immune infiltrates in CSF and post-therapy tumor did not generally correlate, a fraction of expanded T cell receptors (TCRs) was seen to overlap between CSF and tumor. This has important implications for what samples are collected on these trials and how they are analyzed. These initial findings provide support for continued investigation into locoregionally-delivered IL13BBζ-CAR T cells for children with brain tumors.

Cell type-specific and disease-associated eQTL in the human lung

Common genetic variants confer substantial risk for chronic lung diseases, including pulmonary fibrosis (PF). Defining the genetic control of gene expression in a cell-type-specific and context-dependent manner is critical for understanding the mechanisms through which genetic variation influences complex traits and disease pathobiology. To this end, we performed single-cell RNA-sequencing of lung tissue from 67 PF and 49 unaffected donors. Employing a pseudo-bulk approach, we mapped expression quantitative trait loci (eQTL) across 38 cell types, observing both shared and cell type-specific regulatory effects. Further, we identified disease-interaction eQTL and demonstrated that this class of associations is more likely to be cell-type specific and linked to cellular dysregulation in PF. Finally, we connected PF risk variants to their regulatory targets in disease-relevant cell types. These results indicate that cellular context determines the impact of genetic variation on gene expression, and implicates context-specific eQTL as key regulators of lung homeostasis and disease.

An integrated cell atlas of the lung in health and disease

Single-cell technologies have transformed our understanding of human tissues. Yet, studies typically capture only a limited number of donors and disagree on cell type definitions. Integrating many single-cell datasets can address these limitations of individual studies and capture the variability present in the population. Here we present the integrated Human Lung Cell Atlas (HLCA), combining 49 datasets of the human respiratory system into a single atlas spanning over 2.4 million cells from 486 individuals. The HLCA presents a consensus cell type re-annotation with matching marker genes, including annotations of rare and previously undescribed cell types. Leveraging the number and diversity of individuals in the HLCA, we identify gene modules that are associated with demographic covariates such as age, sex and body mass index, as well as gene modules changing expression along the proximal-to-distal axis of the bronchial tree. Mapping new data to the HLCA enables rapid data annotation and interpretation. Using the HLCA as a reference for the study of disease, we identify shared cell states across multiple lung diseases, including SPP1+ profibrotic monocyte-derived macrophages in COVID-19, pulmonary fibrosis and lung carcinoma. Overall, the HLCA serves as an example for the development and use of large-scale, cross-dataset organ atlases within the Human Cell Atlas.

EPCO-18. MULTI-MODAL AND MULTI-TISSUE PROFILING OF GBM PATIENTS TREATED WITH CAR T CELL THERAPY TO ELUCIDATE MOLECULAR MECHANISMS OF VARIATION IN TREATMENT RESPONSE

Recent advances in immunotherapy, particularly chimeric antigen receptor (CAR)-engineered T cell therapy, have shown promise for the treatment of many tumor types including progressive recurrent glioblastoma (GBM). While early phase clinical trials have illuminated the potential for CAR T cell therapy to effectively treat GBM, they have also highlighted the unique challenges regarding the efficacy and safety of immunotherapy for brain tumors, and many patients continue to progress during therapy. We seek to overcome these challenges and ultimately extend the time of survival for patients diagnosed with GBM by investigating the immune- and tumor-mediated mechanisms driving variation in response to CAR T cell therapy. We generated the first multi-omics time-series dataset of CAR T cells, endogenous immune cells, and tumor cells from 59 GBM patients treated with CAR T cell therapy. Using single cell RNA-sequencing and simultaneous quantification of nearly 200 cell surface proteins, we comprehensively profiled the cellular phenotypes and signaling pathways within tumor and circulating immune cells that are associated with treatment response. The combination of mRNA and protein expression allowed us to resolve cell states beyond what either modality was capable of alone. Additionally, we found differentially expressed genes and proteins between tumor biopsies collected before and after CAR T cell therapy as well as differential expression between pre-infusion CAR T cells and those identified within the tumor following infusion. By evaluating the CAR T cell phenotypes prior to and during treatment we sought to address the outstanding question of how intrinsic variability impacts the activity and persistence of CAR T cells and to determine the phenotypes that confer the greatest therapeutic benefit for patients with GBM. Our results have direct implications for precision medicine and future clinical trials investigating the use of CAR T cell therapy for GBM as well as other solid tumors.

Single-cell RNA sequencing reveals profibrotic roles of distinct epithelial and mesenchymal lineages in pulmonary fibrosis

Pulmonary fibrosis (PF) is a form of chronic lung disease characterized by pathologic epithelial remodeling and accumulation of extracellular matrix (ECM). To comprehensively define the cell types, mechanisms, and mediators driving fibrotic remodeling in lungs with PF, we performed single-cell RNA sequencing of single-cell suspensions from 10 nonfibrotic control and 20 PF lungs. Analysis of 114,396 cells identified 31 distinct cell subsets/states. We report that a remarkable shift in epithelial cell phenotypes occurs in the peripheral lung in PF and identify several previously unrecognized epithelial cell phenotypes, including a KRT5- /KRT17 + pathologic, ECM-producing epithelial cell population that was highly enriched in PF lungs. Multiple fibroblast subtypes were observed to contribute to ECM expansion in a spatially discrete manner. Together, these data provide high-resolution insights into the complexity and plasticity of the distal lung epithelium in human disease and indicate a diversity of epithelial and mesenchymal cells contribute to pathologic lung fibrosis.

Corrosion Resistance of Nanosized Silicon Carbide-Rich Composite Coatings Produced by Noble Gas Ion Mixing

Ion beam mixing has been used to produce a silicon carbide (SiC)-rich nanolayer for protective coating. Different C/Si/C/Si/C/Si(substrate) multilayer structures (with individual layer thicknesses falling in the range of 10-20 nm) have been irradiated by Ar⁺ and Xe⁺ ions at room temperature in the energy and fluence ranges of 40-120 keV and 1-6 × 10¹⁶ ion/cm², respectively. The effects of ion irradiation, including the in-depth distribution of the SiC produced, was determined by Auger electron spectroscopy depth profiling. The thickness of the SiC-rich region was only some nanometers, and it could be tailored by changing the layer structure and the ion irradiation conditions. The corrosion resistance of the layers was investigated by potentiodynamic electrochemical test in 4 M KOH solution. The measured corrosion resistance of the SiC-rich layers was orders of magnitude better than that of pure silicon, and a correlation was found between the corrosion current density and the effective areal density of the SiC.

Share 35 changes in center-level liver acceptance practices

Share 35 was implemented to provide improved access to organs for patients with Model for End-Stage Liver Disease (MELD) scores ≥ 35. However, little is known about the impact of Share 35 on organ offer acceptance rates. We evaluated all liver offers to adult patients who were ultimately transplanted between January 1, 2011 and December 31, 2015. The analyses focused on patients ranked in the top 5 positions of a given match run and used multilevel mixed-effects models, clustering on individual wait-list candidate and transplant center. There was a significant interaction between Share 35 era and MELD category (P < 0.001). Comparing offers to MELD score ≥ 35 patients, offers after Share 35 were 36% less likely to be accepted compared with offers to MELD score ≥ 35 patients before Share 35 (adjusted odds ratio, 0.64). There was no clinically meaningful difference in the donor risk index of livers that were declined for patients with an allocation MELD score ≥35 in the pre- versus post-Share 35 era. Organ offer acceptance rates for patients with an allocation MELD ≥ 35 decreased in every region after Share 35; the magnitude of these changes was bigger in regions 2, 3, 4, 5, 6, 7, and 11, compared with regions 8 and 9 that had regional sharing in place before Share 35. There were significant changes in organ offer acceptance rates at the center level before versus after Share 35, and these changes varied across centers (P < 0.001). In conclusion, in liver transplantation candidates achieving a MELD score ≥ 35, liver acceptance of offers declined significantly after implementation of Share 35. The alterations in behavior at the center level suggest that practice patterns changed as a direct result of Share 35. Changes in organ acceptance under even broader organ sharing (redistricting) would likely be even greater, posing major logistical and operational challenges, while potentially increasing discard rates, thus decreasing the total number of transplants nationally. Liver Transplantation 23 604-613 2017 AASLD.

Comparison of methods for the evaluation of NIBP from pulse transit time

Non-invasive blood pressure measurement (NIBP) is one of the most discussed topic in cardiovascular medicine. Currently continuous measurement of blood pressure is possible by invasive methods, which makes the measurement impractical for Doctors and uncomfortable for the patients. It is possible to use special devices to measure blood pressure noninvasively continuously but there are still some problems with long time monitoring and comfort for patient. Physiologically there is connection between electrical and mechanical heart functions, propagation of pulse wave and blood pressure value. Our paper investigates various methods for the evaluation of NIPB from pulse transit time. We analyse real signals which we obtained during surgical interventions in Hospital, with invasive measurements of blood pressure waves, and non-invasive measurements of pulse waves and ECG signal.

Abstract P4-12-16: Safety profile and costs of related adverse events of trastuzumab emtansine compared to other regimens in the Canadian health care system

Background

Trastuzumab Emtansine (T-DM1) is an antibody–drug conjugate (ADC) comprised of the microtubule inhibitory cytotoxic agent DM1 and trastuzumab which, in addition to its antitumor properties, targets T-DM1 to HER2–overexpressing cells. The phase III EMILIA study compared the safety and efficacy of T-DM1 (n = 496) versus capecitabine plus lapatinib (CAP+LAP, n = 495) in patients with HER2-positive locally advanced or MBC previously treated with trastuzumab and a taxane. The phase II TDM4450g study compared the safety and efficacy of T-DM1 (n = 67) versus trastuzumab plus docetaxel (TRAZ+DOCE, n = 70) in patients with previously untreated MBC. These trials demonstrated statistically and clinically meaningful differences between T-DM1 and its comparators. In the EMILIA trial, the proportion of patients who developed grade ≥3 treatment-related AEs that were deemed related to treatment by the investigators was lower in the T-DM1 arm (30.6%) compared to the CAP+LAP arm (48.8%) and 5.9% of patients on T-DM1 discontinued treatment due to an AE, compared with 10.7% of patients on CAP+LAP.

In the TDM4450g study, the proportion of patients who developed grade ≥3 AEs that were deemed related to treatment by the investigators was lower in the T-DM1 arm (33.3%) versus the TRAZ+DOCE arm (81.82%) and 7.2% of patients on T-DM1 discontinued treatment due to an AE, compared with 34.8% of patients on TRAZ+DOCE.

The objective of this analysis was to estimate and compare the Canadian costs of managing the treatment-related AEs of T-DM1 as reported in the EMILIA and TDM4450g trials, from the perspective of Canadian public payers.

Methods

An Excel based spreadsheet model was utilized to estimate the costs of managing the treatment-related AEs. Clinical data (number and severity of AEs) were obtained from the two trials. Resource utilization and costing information were obtained from the literature, clinical experts, and Canadian standard costing sources (minimum and maximum costs were used). Costs were reported as 2012 CAD. The AEs that were considered for costing in this analysis were all treatment-related grade ≥3 AEs as well as grade 2 AEs that occurred in ≥5% of patients in both arms of either study.

Results

The management of treatment-related AEs by using T-DM1 resulted in cost savings ranging from $1,684 - $8,036 versus CAP+LAP as reported in the EMILIA trial and from $4,326 - $25,402 versus TRAZ+DOCE as per the TDM4450g trial (see Table 1).

Table 1: Range of Costs of Managing Treatment-Related AEs as Reported in the EMILIA and TDM4450g trials EMILIATDM4450g T-DM1CAP + LAPT-DM1TRAZ+DOCECost per patient$1,376 - $2,463$3,060 - $10,499$798 - $2,215$5,124 - $27,617Cost savings$1,684 - $8,036$4,326 - $25,402

Conclusions

This analysis demonstrated that utilizing T-DM1 for the management of HER2-positive MBC results in significant cost savings of related AEs management due to the improved safety profile compared to CAP+LAP and TRAZ+DOCE.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-12-16.

[Impact of physical activity level on alexithymia and coping strategies in an over-40 multiple sclerosis population: a pilot study]

INTRODUCTION

The aim of this study was to evaluate the impact of physical activity on alexithymia and coping strategies among people with multiple sclerosis aged over 40. The hypotheses were that physical activity should have a protective effect on alexithymia, and more particularly, on "emotional identification" and could influence coping strategies because it can be considered as a distractive coping strategy.

METHODS

Thirty-seven patients aged 40 years or older were asked to complete a form including an identification sheet and standardized questionnaires: the Bermond-Vorst Alexithymia Questionnaire (version B), the Coping with Health Injuries and Problem Questionnaire, the Fatigue Impact Scale, and the Hospital Anxiety and Depression Scale.

RESULTS

The participants with a high or moderate level of physical activity used "information research" as a coping strategy better than those who had a lower level of physical activity. They also analyzed their emotions better. The results revealed an association between these variables and anxiety, depression and fatigue.

DISCUSSION

This study provides insight for future research about the impact of physical activity on multiple sclerosis.

Circulating endothelial progenitor cells and depression: a possible novel link between heart and soul

Although depression is known to be an independent risk factor for cardiovascular disorders, the mechanisms behind this connection are not well understood. However, the reduction in the number of endothelial progenitor cells (EPCs) in patients with cardiovascular risk factors has led us to hypothesize that depression influences the number of EPCs. EPCs labeled with CD34, CD133 and vascular endothelial growth factor receptor-2 (VEGFR2) antibodies were counted by flow cytometry in the peripheral blood (PB) of 33 patients with a current episode of major depression and of 16 control subjects. Mature (CD34+/VEGFR2+) and immature (CD133+/VEGFR2+) EPC counts were decreased in patients (vs controls; P<0.01 for both comparisons), and there was a significant inverse relationship between EPC levels and the severity of depressive symptoms (P<0.01 for both EPC phenotypes). Additionally, we assayed the plasma levels of VEGF, C-reactive protein (CRP) and tumor necrosis factor (TNF)-alpha and observed significantly elevated TNF-alpha concentrations in patients (vs controls; P<0.05) and, moreover, a significant inverse correlation between TNF-alpha and EPC levels (P<0.05). Moreover, by means of a quantitative RT-PCR approach, we measured CD34, CD133 and VEGFR2 mRNA levels of PB samples and found a net trend toward a decrease in all the investigated EPC-specific mRNA levels in patients as compared with controls. However, statistical significance was reached only for VEGFR2 and CD133 levels (P<0.01 for both markers). This is the first paper that demonstrates evidence of decreased numbers of circulating EPCs in patients with a current episode of major depression.

The impact of preoperative breast magnetic resonance imaging (MRI) on surgical decision-making in young patients with breast cancer

Abstract #4012

Recent data suggests that breast MRI is a more sensitive diagnostic test for detecting invasive breast cancer than mammography or breast ultrasound. Breast MRI may be particularly useful in younger premenopausal women with higher density breast tissue for differentiating between dense fibroglandular breast tissue and breast malignancies. The primary objective of this study was to determine the impact of pre-operative breast MRI on surgical decision-making in young women with breast cancer.&#x2028; Methods: A retrospective review of 32 patients with newly diagnosed invasive breast cancer and age ≤ 50 was performed. All patients underwent a physical examination, preoperative mammogram, breast ultrasound, and bilateral breast MRI. Two breast cancer surgeons reviewed the preoperative mammogram report, breast ultrasound report, and physical examination summary for each case and were asked if they would recommend a lumpectomy, quandrantectomy, or mastectomy. A few weeks later, the two surgeons were shown the same information with the breast MRI report and were asked what type of surgery they would now recommend. In each case, MRI was classified by two adjudicators as having affected the surgical outcome in a positive, negative, or neutral fashion. A 'Positive Impact' was defined as the situation where breast MRI detected additional disease that was not found on physical exam, mammogram, or breast ultrasound and led to an appropriate change in surgical management. A 'Negative Impact' was defined as the situation where the breast MRI results led the surgeon to recommend more extensive surgery, with less extensive disease actually found at pathology. 'No Impact' was defined as the situation where MRI findings did not alter surgical recommendations or outcome.&#x2028; Results: The median age was 41.5 years. The pathologic diagnosis was invasive ductal carcinoma in 94% (30/32) and invasive lobular carcinoma in 6% (2/32) of cases. For surgeon A, clinical management was altered in 21/32 (66%) of cases, and for surgeon B, management was altered in 13/32 (41%) of cases. The most common change in surgical decision-making after breast MRI was from breast conserving surgery to a mastectomy. Mastectomy rates were similar between both surgeons after breast MRI. After reviewing the pathology results and comparing them with the breast MRI results, it was determined that breast MRI led to a positive outcome in 13/32 cases (41%). Breast MRI led to no change in surgical management in 15/32 (47%) cases and resulted in a negative change in surgical management in 4/32 (13%) cases. Bilateral breast MRI detected a contralateral breast cancer in 2/32 (6%) patients.&#x2028; Conclusions: Preoperative breast MRI appears to result in a change in surgical management in a significant proportion of younger women. Further research is needed to determine if this change in surgical decision-making will result in improved local control.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4012.

Acute neurological deterioration in ovarioleukodystrophy related to EIF2B mutations: pregnancy with oocyte donation is a potentially precipitating factor

Mutations in the eukaryotic translation initiation factor 2B (eIF2B) represent a heterogenous group of autosomal recessive leucodystrophy characterized by a diffuse CSF-like aspect of the white matter at MRI designed as vanishing white matter (VWM) and episodes of acute deterioration after stresses. The mild juvenile and adult forms are often associated with primary ovarian failure, a syndrome referred to as ovarioleukodystrophy (OLD). We reported case of a woman with OLD who successfully underwent in vitro fertilization with donated oocytes and embryo transfer. Pregnancy was complicated by a non-convulsive epileptic status leading to the identification of compound heterozygous EIF2B5 mutation (p.Arg113His and p.Arg299His). The patient gave birth to a healthy child by Caesarean section. In conclusion, we report for the first time that in vitro fertilization and embryo transfer can lead to a successful procreation in patients with OLD related to EIF2B mutations. However this procedure must be considered with cautiousness, because of its potential neurological risks.

Opsoclonus-myoclonus as a manifestation of Lyme disease

Opsoclonus-myoclonus syndrome (OMS) is a rare condition that includes chaotic multidirectional saccadic eye movements associated with myoclonus and ataxia. In adults, it is usually considered to be an autoimmune disease occurring either in a paraneoplastic context or after central nervous system infection. We report the case of a patient who presented with the classic features of OMS as a manifestation of acute Borrelia burgdorferi infection that was shown both on serum and cerebrospinal fluid examination. The outcome was favourable after prolonged antibiotic treatment. Lyme disease could be added to the list of aetiologies to be screened in OMS, as it would allow effective treatment and avoidance of unnecessary investigations.

[Rhinocerebral mucormycosis]

INTRODUCTION

Mucormycosis is a rare and acute fungal infection which is frequently lethal. The rhinocerebral form is usually seen in diabetics, but other localizations may occur in severely immunocompromised subjects.

OBSERVATION

We report the case of a sphenoidal sinusitis associated with a probable cavernous sinus thrombosis and carotid artery thrombosis with middle cerebral artery territory infarction. Diagnosis was made on histological examination following sphenoidotomy. Early medical and surgical treatment led to a good outcome.

CONCLUSION

The diagnosis of rhinocerebral mucormycosis should be considered in the clinical setting of necrotic sinusitis and acute neurologic deficit in diabetic patients. Early diagnosis and treatment are crucial factors leading to a good outcome.

[Delayed post-anoxic leukoencephalopathy]

INTRODUCTION

The onset of post-anoxic encephalopathies can be delayed after the acute hypoxic injury.

CASE REPORT

We present the case of a 45-year-old woman who achieved complete recovery from an episode of hypoxia related to a suicide attempt (ingestion of benzodiazepine). Three weeks later she developed a confusional state with akinetic mutism and parkinsonism. Brain CT-scan showed bilateral hemispheric white matter hypodensities. MRI showed extensive bilateral hyperintensities on T2-weighted and Flair sequences within the hemispheric white matter and the globus pallidus. EEG showed diffuse slow activity. All investigations for leukodystrophies were negative. Brain biopsy showed normal cortex and widespread demyelination with axonal sparing in the underlying white matter. The patient experienced a partial clinical recovery.

CONCLUSION

The clinical course and the results of paraclinic investigations were consistent with the diagnosis of delayed post-anoxic leukoencephalopathy.

Metabolic control in patients with type 2 diabetes using Humalog Mix50 injected three times daily: crossover comparison with human insulin 30/70

OBJECTIVE

Patients with type 2 diabetes most frequently use injections of premixed insulin formulations twice daily, but intensified insulin therapy may provide better control. This study was designed to compare metabolic control with three daily injections of Humalog Mix50 or premixed human insulin 30/70 (30 % regular/70 % NPH) twice daily in accordance with normal prescription practice.

RESEARCH DESIGN AND METHODS

The study cohort of 40 patients with type 2 diabetes used a two-way, crossover design. Patients were randomized to either Mix50 at each main meal or human insulin 30/70 at breakfast and dinner for 3 months, followed by the alternate treatment for 3 months. Blood glucose was measured by the patients at baseline and at the end of each treatment sequence. No significant carryover effects were observed, so treatment sequences were combined and data analyzed by unpaired t-tests.

RESULTS

Mean blood glucose level was significantly (p = 0.010) decreased with Mix50 but not with 30/70 (p = 0.237), and there was a significant difference between treatments at the endpoint (p = 0.035). Fasting blood glucose was increased pre-breakfast and decreased at bedtime with Mix50 but was not significantly changed pre-lunch or dinner or at any time with 30/70 insulin. Blood glucose excursions were significantly decreased with Mix50 after breakfast (p = 0.002), lunch (p < 0.001) and dinner (p = 0.037) but not significantly changed from baseline with 30/70 insulin. The decrease from baseline in HbA (1c) was significantly (p = 0.021) greater with Mix50 than with 30/70 insulin. There were no significant differences between treatments regarding incidence of hypoglycemia or adverse events.

CONCLUSIONS

In patients with type 2 diabetes, a regimen of Humalog Mix50 administered three times daily before meals maintains glucose control more effectively than premixed human insulin 30/70 administered before breakfast and dinner.

ABC of one to seven. Services for children: primary care

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ABC of one to seven. Audit in primary care paediatrics

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Histological studies on the development of retinotectal projections from nasoventral quarter-eyes in Xenopus laevis

In Xenopus larvae, the size and location of the retinotectal projection of nasoventral quarter-eyes was analyzed in early stages (43–47), midlarval stages (50 and 53) and metamorphic stages (56 and 60), by labelling the optic nerve with the cobalt-lysine complex or with horseradish-peroxidase (HRP). For direct comparison, both fragment and normal eye projections were determined simultaneously in the same specimen in brain whole mounts. During early stages (up to stage 47), the projection fields of normal eyes and quarter-eyes are confined to the rostral part of the tectum. The extension of the projection in rostrocaudal direction of eye fragments does not differ from that of normal eyes. During later development up to metamorphosis, normal eyes expand their projection over the newly formed tectal surface in a caudal direction, whereas the fiber terminations of nasoventral quarter-eyes still remain in the rostral part of the tectum. Quantitative studies revealed that there is no difference in the size of both halves of the tectum. At least for quarter-eyes, however, a strict correlation between eye size and extension of the contralateral projection field could be established. According to our results, it is unlikely that during development local tectal markers are involved in determining the location of the projection field and the retinotopic ordering of the optic fibers. Instead we suggest that the optic fibers separate in accordance with their retinal specificity.

In defense of genuine ignorance: supporting vitality and relevance in graduate curricula

Genuine ignorance, defined by John Dewey as curiosity and openmindedness in opposition to repetition of catch phrases and familiar propositions, is nurtured in graduate nursing curricula in which the educational process is congruent with course content. Preparation for advanced practice in the mental health environment of the foreseeable future required abandonment of the familiar medical model in favor of conceptual models consistent with current thinking in psychiatric nursing and exposure to current problems (homelessness, family violence, AIDS) and current problem solving strategies (brief treatment, family preservation). Involvement in practice-based research and operationalizing new perspectives on familiar clinical problems, are suggested as strategies for developing the advanced practitioner. Two of the authors, former graduate students, describe the impact of changed perspectives and research activity on their own practice.

Practice activity analysis: collaboration between general practitioners and a family practitioner committee

The Brent and Harrow family practitioner committee has supported a scheme to enable general practitioners to collect data relating to their practice activity. This paper reports on the operation of the scheme involving 76 general practitioners from 22 practices and the findings. Practice nurse activity was also included. The family practitioner committee undertook an analysis of the data and provided each participating general practitioner with a print-out of his or her consultation rates over a range of activity, enabling general practitioners to make comparisons both with their partners and with the averages for all the practices participating in the scheme. The essential aim is to provide structured information which enables general practitioners to look more objectively at their activity. The family practitioner committee gave an assurance that the figures would not be used to criticize individuals.

ABC of 1 to 7 (revised). Services for children: primary care

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[Necrotizing circumscribed scleroderma after cupping therapy in arterial occlusion]

A 50-year-old man suffering from arterial occlusion developed deep ulcerations after cupping therapy of circumscribed scleroderma on his right thigh.

Mucormycotic infection in mice following prolonged incubation of spores in vivo and the role of spore agglutinating antibodies on spore germination

Following intranasal inoculation of mice, Rhizomucor pusillus spores are gradually cleared from the lung, with the clearance complete at 30 days. Incubation of R. pusillus spores in vivo for up to 14 days after intranasal inoculation resulted in pulmonary mucormycosis when the mice were then treated with cortisone. Spore-agglutinating IgM antibodies were detected in normal adult mice and R. pusillus-inoculated but not cortisone-treated mice. There was no correlation between antispore antibody titers and spore germination in vitro. The absence of germinated R. pusillus in inoculated but non-cortisone-treated mice appears to be due to a reversible inhibition of spore germination rather than destruction of spores by the host. The factor(s) that restrict spore germination are reversible and do not appear to be spore agglutinating antibodies.

ABC of 1 to 7: services for children: primary care

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