Extracellular vesicles released by transforming growth factor-beta 1-preconditional mesenchymal stem cells promote recovery in mice with spinal cord injury

Spinal cord injury (SCI) causes neuroinflammation, neuronal death, and severe axonal connections. Alleviating neuroinflammation, protecting residual cells and promoting neuronal regeneration via endogenous neural stem cells (eNSCs) represent potential strategies for SCI treatment. Extracellular vesicles (EVs) released by mesenchymal stem cells have emerged as pathological mediators and alternatives to cell-based therapies following SCI. In the present study, EVs isolated from untreated (control, C-EVs) and TGF-β1-treated (T-EVs) mesenchymal stem cells were injected into SCI mice to compare the therapeutic effects and explore the underlying mechanisms. Our study demonstrated for the first time that the application of T-EVs markedly enhanced the proliferation and antiapoptotic ability of NSCs in vitro. The infusion of T-EVs into SCI mice increased the shift from the M1 to M2 polarization of reactive microglia, alleviated neuroinflammation, and enhanced the neuroprotection of residual cells during the acute phase. Moreover, T-EVs increased the number of eNSCs around the epicenter. Consequently, T-EVs further promoted neurite outgrowth, increased axonal regrowth and remyelination, and facilitated locomotor recovery in the chronic stage. Furthermore, the use of T-EVs in Rictor-/- SCI mice (conditional knockout of Rictor in NSCs) showed that T-EVs failed to increase the activation of eNSCs and improve neurogenesis sufficiently, which suggested that T-EVs might induce the activation of eNSCs by targeting the mTORC2/Rictor pathway. Taken together, our findings indicate the prominent role of T-EVs in the treatment of SCI, and the therapeutic efficacy of T-EVs for SCI treatment might be optimized by enhancing the activation of eNSCs via the mTORC2/Rictor signaling pathway.

Subtyping of triple-negative breast cancers: its prognostication and implications in diagnosis of breast origin

BACKGROUND

Triple-negative breast cancer (TNBC) subtyping by gene profiling has provided valuable clinical information. Here, we aimed to evaluate the relevance of TNBC subtyping using immunohistochemistry (IHC), which could be a more clinically practical approach, for prognostication and applications in patient management.

METHODS

A total of 123 TNBC cases were classified using androgen receptor (AR), CD8, Forkhead box C1 protein (FOXC1), and doublecortin-like kinase 1 (DCLK1) into luminal androgen receptor (LAR), basal-like immunosuppressive (BLIS), mesenchymal-like (MES), and immunomodulatory (IM) subtypes. The IM cases were further divided into the IM-excluded and IM-inflamed categories by CD8 spatial distribution. Their clinicopathological and biomarker profiles and prognoses were evaluated.

RESULTS

LAR (28.6%) and MES (11.2%) were the most and least frequent subtypes. The IHC-TNBC subtypes demonstrated distinct clinicopathological features and biomarker profiles, corresponding to the reported features in gene profiling studies. IM-inflamed subtype had the best outcome, while BLIS had a significantly poorer survival. Differential breast-specific marker expressions were found. Trichorhinophalangeal syndrome type 1 (TRPS1) was more sensitive for IM-inflamed and BLIS, GATA-binding protein 3 (GATA3) for IM-excluded and MES, and gross cystic disease fluid protein 15 (GCDFP15) for LAR subtypes.

CONCLUSIONS

Our findings demonstrated the feasibility of IHC surrogates to stratify TNBC subtypes with distinct features and prognoses. The IM subtype can be refined by its CD8 spatial pattern. Breast-specific marker expression varied among the subtypes. Marker selection should be tailored accordingly.

Increased blood flow of spinal cord lesion after decompression improves neurological recovery of degenerative cervical myelopathy: an intraoperative ultrasonography-based prospective cohort study

INTRODUCTION

Surgical decompression is a highly effective therapy for degenerative cervical myelopathy (DCM), but the mechanisms of neurological recovery following decompression remain unclear. This study aimed to evaluate the spinal cord blood flow status after sufficient decompression by intraoperative contrast-enhanced ultrasonography (CEUS) and to analyze the correlation between neurological recovery and postdecompressive spinal cord blood perfusion in DCM.

MATERIALS AND METHODS

Patients with multilevel DCM were treated by ultrasound-guided modified French-door laminoplasty using a self-developed rongeur. Neurological function was evaluated using the modified Japanese Orthopaedic Association (mJOA) score preoperatively and at 12 months postoperatively. Spinal cord compression and cervical canal enlargement before and after surgery were assessed by magnetic resonance imaging and computerized tomography. The decompression status was evaluated in real time by intraoperative ultrasonography, while the spinal cord blood flow after sufficient decompression was assessed by CEUS. Patients were categorized as favourable (≥50%) or unfavourable (<50%) recovery according to the recovery rate of the mJOA score at 12 months postoperatively.

RESULTS

Twenty-nine patients were included in the study. The mJOA scores were significantly improved in all patients from 11.2±2.1 preoperatively to 15.0±1.1 at 12 months postoperatively, with an average recovery rate of 64.9±16.2%. Computerized tomography and intraoperative ultrasonography confirmed adequate enlargement of the cervical canal and sufficient decompression of the spinal cord, respectively. CEUS revealed that patients with favourable neurological recovery had a greater increased blood flow signal in the compressive spinal cord segment after decompression.

CONCLUSIONS

In DCM, intraoperative CEUS can clearly reflect spinal cord blood flow. Patients with increased blood perfusion of the spinal cord lesion immediately after surgical decompression tended to achieve greater neurological recovery.

[Clinicopathological features of low-grade oncocytic renal tumor (CD117-negative, cytokeratin 7-positive): report of seven cases]

Objective: To explore clinicopathological features of low-grade oncocytic tumor (LOT) of the kidney and to analyze its relationship to hybrid oncocytic/chromophobe tumor (HOCT) of the kidney, renal oncocytoma (RO), and chromophobe renal cell carcinoma (chRCC). Methods: Seven LOTs were identified from the pathologic archives of two hospitals, including Xiangya Hospital (5 cases) and the Second Xiangya Hospital (2 cases) of Central South University between 2012 and 2019. Clinical data of the LOTs were collected. The tumor morphology was analyzed and immunohistochemistry was performed. Results: All LOTs occurred in adults, aged from 49 to 72 years (median 56.0 years, mean 60.7 years). The tumor size ranged from 2.5 to 6.0 cm (median 4.3 cm, mean 4.3 cm). There were three male and four female patients. Three cases occurred in the left kidney and four in the right. All the tumors were solitary lesions without the clinicopathologic background of Birt-Hogg-Dubé (BHD) syndrome or oncocytosis. Five patients had available follow-up data (follow-up period 23-95 months, median 69.0 months, mean 64.6 months) and all were alive without disease. Microscopically, all LOTs were well-circumscribed (7/7). Three LOTs were partly encapsulated. The tumors demonstrated a predominant growth pattern comprising prominently compact small nests surrounded by delicately branching thin-walled blood vessels, imparting an organoid architecture (7/7), but variable numbers of glandular or gland-like structures were often seen among the small nests (7/7). There were frequently areas with loose, edematous stroma, and the tumor cells exhibited reticular, trabecular, or single cell arrangements (6/7). Focal hemorrhage was also commonly present in both compact and loose areas (5/7). In addition, focally cystic formation and ossification occurred in the compact area of one case and in the loose area of another case. The tumor cells in LOT showed intermediate cytologic characteristics between RO and chRCC, including abundantly eosinophilic granular cytoplasm, ovoid to round nuclei with mostly smooth contours, discernable small nucleoli (RO features), frequently delicate perinuclear halos, and occasional binucleation (chRCC features). The tumors were typically CK7-positive and CD117-negative (7/7), and variable staining for PAX8 (5/7), P504s (2/7), and vimentin (1/7). They were negative for CK20, CD10 and FOXI1. All tumors retained SDHB immunostaining. Conclusions: LOT is a rare and indolent oncocytic renal tumor with homogeneously intermediate cytologic features between RO and chRCC. There are some clinicopathologic overlaps between LOT and sporadic HOCT. The distinctive morphology and immunophenotype of LOT suggest that it is potentially a distinct tumor entity.

Decision-making capacity regarding healthcare, welfare and finances in a secure forensic setting

Introduction

Impairment in decision-making capacity is a serious consequence of executive dysfunction secondary to serious mental disorders like schizophrenia. Functional mental capacity (FMC) refers to an individual’s ability to make and communicate legally competent decisions autonomously. Studies have shown that FMC is dependent on severity of psychosis and can improve with treatment.

Objectives

To ascertain the correlation between the scores on a structured judgement tool, namely the Dundrum Capacity Ladders (DCL) with level of acuity of treatment setting and length of stay in a secure forensic hospital.

Methods

Sixty-two patients were interviewed using the DCL across three domains – healthcare, welfare and finances. Correlation between DCL scores, length of hospital stay and level of acuity of treatment setting was assessed.

Results

As patients moved from higher to lower dependency wards, mean DCL score increased, indicating a higher level of capacity. Patients in high dependency wards were most impaired while those in the low dependency wards performed significantly better (r_s=0.472, p<0.001). The longer the patients stayed in the hospital, up until five years, the higher the mean welfare domain score (r_s=0.402, p=0.011) and mean DCL score (r_s=0.376, p=0.018). Beyond five years of hospital stay, those who had lower DCL scores and did not improve had longer length of stay.

Conclusions

Patients’ FMC improve as they progress from high to low level of acuity of treatment setting. However, this is dependent on the length of hospital stay. FMC may be a measure of recovery in the forensic setting.

Disclosure

No significant relationships.

Zero violence or zero seclusion. Which is more acceptable in our hospitals?

Introduction

There is an established association between serious mental illness and violence. Secure forensic psychiatric services provide care and treatment to mentally disordered offenders. The majority of patients in forensic services suffer from severe mental illnesses such as schizophrenia, with co-morbid polysubstance abuse and maladaptive personality traits. Psychiatric services are under significant pressure to reduce the use of seclusion and restrictive practices, whilst mandated to provide safe environments for patients and staff.

Objectives

To determine the number and characteristics of violent incidents in a secure forensic hospital in Ireland.

Methods

A retrospective review of all incidents in Central Mental Hospital, Ireland between 1^st March 2019 and 31^st August 2021 was completed. Incidents were categorised into physical assaults and other violent incidents. Demographic measures and measures of violence risk (HCR-20), functioning (GAF), programme completion and recovery (DUNDRUM tool) were collated.

Results

A total of 321 incidents took place during the period examined, of which 47 (14.6%) involved physical assaults perpetrated by patients. Between March 2020 and August 2021, numbers of assaults increased by 50% and 78% compared to the preceding six-month period respectively. The majority of assaults were committed by a relatively small group of patients. Victims of assaults were more likely to be patients (n=27, 57.4%) and more likely to be males (n=43, 91.9%).

Conclusions

Physical assaults and other violent incidents happen in forensic and general psychiatric units. Restrictive practices, used in accordance with the law, are necessary at times to prevent serious harm to patients and staff in psychiatric hospitals.

Disclosure

No significant relationships.

Treatment of glioblastoma using multicomponent silica nanoparticles

Glioblastomas (GBMs) remain highly lethal. This partially stems from the presence of brain tumor initiating cells (BTICs), a highly plastic cellular subpopulation that is resistant to current therapies. In addition to resistance, the blood-brain barrier limits the penetration of most drugs into GBMs. To effectively deliver a BTIC-specific inhibitor to brain tumors, we developed a multicomponent nanoparticle, termed Fe@MSN, which contains a mesoporous silica shell and an iron oxide core. Fibronectin-targeting ligands directed the nanoparticle to the near-perivascular areas of GBM. After Fe@MSN particles deposited in the tumor, an external low-power radiofrequency (RF) field triggered rapid drug release due to mechanical tumbling of the particle resulting in penetration of high amounts of drug across the blood-brain tumor interface and widespread drug delivery into the GBM. We loaded the nanoparticle with the drug 1400W, which is a potent inhibitor of the inducible nitric oxide synthase (iNOS). It has been shown that iNOS is preferentially expressed in BTICs and is required for their maintenance. Using the 1400W-loaded Fe@MSN and RF-triggered release, in vivo studies indicated that the treatment disrupted the BTIC population in hypoxic niches, suppressed tumor growth and significantly increased survival in BTIC-derived GBM xenografts.

Delivery of drugs into brain tumors using multicomponent silica nanoparticles

Glioblastomas are highly lethal cancers defined by resistance to conventional therapies and rapid recurrence. While new brain tumor cell-specific drugs are continuously becoming available, efficient drug delivery to brain tumors remains a limiting factor. We developed a multicomponent nanoparticle, consisting of an iron oxide core and a mesoporous silica shell that can effectively deliver drugs across the blood-brain barrier into glioma cells. When exposed to alternating low-power radiofrequency (RF) fields, the nanoparticle's mechanical tumbling releases the entrapped drug molecules from the pores of the silica shell. After directing the nanoparticle to target the near-perivascular regions and altered endothelium of the brain tumor via fibronectin-targeting ligands, rapid drug release from the nanoparticles is triggered by RF facilitating wide distribution of drug delivery across the blood-brain tumor interface.

Abstract P2-03-03: BRG1-SOX4 mediates a novel and essential signaling network that activates PI3K/Akt signaling in TNBC

Background:

Triple negative (TNBC) breast cancer, which is largely synonymous with the basal-like molecular subtype, is an aggressive malignancy that accounts for nearly 1 in 4 breast cancer related deaths and disproportionately affects younger women and women of African American decent. Given the lack of drug-able targets expressed by TNBC tumors, few therapeutic options exist beyond currently utilized cytotoxic therapies, and the overall prognosis for these patients remains poor. While TNBC tumors are characterized by high PI3K signaling, clinical trials targeting this pathway have had limited success. Therefore, identifying mechanisms driving key oncogenic pathways, including PI3K, is paramount to understanding the transformation process and enabling the development of rational, personalized therapeutic regimens.

Methods:

We utilized a PI3K gene expression signature as a conceptual framework to analyze genome-wide mRNA expression and DNA copy number data from human breast tumors to identify genetic drivers of PI3K/Akt signaling. Kinome profiling was used to identify changes in the drug-able kinome regulated by these genes and in vitro studies were used to delineate mechanisms by which identified genes mediate oncogenic PI3K signaling in TNBC.

Results:

Integrative proteogenomic analyses of orthogonal genome-wide data from ˜3,000 human tumors from the TCGA and METABRIC studies identified amplification and overexpression of the oncogenic transcription factor SOX4 as well as the SWI/SNF ATPase BRG1 in tumors with high PI3K activity. These alterations were predominantly expressed in TNBC or basal-like breast tumors. Chromatin immunoprecipitation followed by DNA sequencing (ChIPseq) as well as shRNA-based studies confirmed that BRG1 regulates SOX4 expression in TNBC cell lines. Analyses of data from a genome-wide RNA interference (RNAi) screen in 27 breast cancer cell lines further indicated that SOX4 is essential in cell lines with high PI3K activity and this was confirmed by colony formation and cell proliferation assays. Importantly, in vitro analyses confirmed that both BRG1 and SOX4 regulate Akt phosphorylation and down-stream signaling. Profiling of the drug-able kinome in SOX4 depleted cell lines compared to control cells using Multiplexed kinase Inhibitor Beads couple with quantitative Mass Spectrometry (MIB/MS) identified 21 drug-able kinases regulated by SOX4 activity including TGFBR2 which has been previously shown to regulate PI3K activity. RNA sequencing (RNAseq) and RT-PCR analyses confirmed that SOX4 mediates TGFBR2 mRNA levels and co-immunoprecipitation experiments in conjunction with ChIP assays demonstrated that BRG1 and SOX4 form a complex at the TGFBR2 promoter and enhancer region to regulate TGFBR2 expression.

Superficial heat reduction technique for a hybrid microwave-optical device

Microwave applicator in the form of a circularly polarized microstrip patch antenna is proposed to provide localized deep heating in biological tissue, which causes blood vessels to dilate leading to changes in tissue oxygenation. These changes are monitored by an integrated optical system for studying thermoregulation in different parts of the human body. Using computer simulations, this paper compares circularly and linearly polarized antennas in terms of the efficiency of depositing electromagnetic (EM) energy and the heating patterns. The biological model composes of the skin, fat and muscle layers with appropriate dielectric and thermal properties. The results show that for the same specific absorption rate (SAR) in the muscle, the circularly polarized antenna results in a lower SAR in the skin-fat interface than the linearly polarized antenna. The thermal distribution is also presented based on the biological heat equation. The proposed circularly polarized antenna shows heat reduction in the superficial layers in comparison to the linearly polarized antenna.

Mechanism of regulating the expression of lambdaN gene by ribosomal protein at translational level

In ribosomal protein S12 mutant or L24 mutant the expression of lambdaN gene was depressed at translational level. To study its mechanism the lambdaN gene region of lambdaN -lacZ gene fusion was trimmed from its 5' end to 3' end with DNA exonuclease III (DNA exoIII) in order to alter the TIR (translational initiation region) and the coding region of lambdaN gene. After DNA sequencing 23 species of different lambdaN-lacZ fused genes were obtained. The beta-galactosidase activities of these deletants in ribosomal protein mutant were compared with that in wild type strain. The result indicated that (i) S12 mutant could affect 305 subunit's binding to the TIR of lambdaN gene messenger and cause the difficulty in forming 30s initiation complex and then decrease the efficiency of translational initiation; (ii) in S12 mutant the coding region of lambdaN gene also affected the expression lambdaN gene; (iii) in L24 mutant the inhibition of lambdaN gene expression was not related to translational initiation and the 5' end of the coding region of lambdaN gene, but related to the 3' end of lambdaN gene.

Gene modulatory effects, pharmacokinetics, and clinical tolerance of interferon-alpha1b: a second member of the interferon-alpha family

Interferon-alpha1 (IFN-alpha1), which may have a primary role in innate immunity, differs significantly in amino-acid sequence from IFN-alpha2, the only recombinant IFN-alpha with substantial clinical evaluation. Patients with metastatic malignancies received daily subcutaneous doses of 1.5-270 mug/m(2) of recombinant IFN-alpha1b. Gene modulation, pharmacokinetics, tolerability, and disease response were determined. Significant (P<0.01) dose and gene-dependent increases of 2-10 fold occurred in IFN-stimulated genes, including four (tumor necrosis factor-related apoptosis-inducing ligand, cig 5, p56, GEM) never previously identified as increased in patients; significant increases (P<0.01) resulted at the lowest dose (1.5 microg/m(2); 1.5 x 10(4) human antiviral units/m(2)). Increases (P<0.01) were sustainable for >4 weeks. Peak levels of IFN-alpha1b were at 3 h; an increase of approximately eightfold in both C(max) and AUC occurred between 15 microg/m(2) and 270 microg/m(2). Chronic toxicities of anorexia, weight loss, and fatigue were relatively uncommon. Eighteen patients were treated for >8 weeks; none experienced >grade 1 weight loss. Three patients at the highest dose developed grade 3 fatigue after > or =3 months, which required dose reduction or discontinuation. Patient acceptability of fatigue defined a dose for initiation of Phase II trials, 270 microg/m(2). Six patients (five with renal cell carcinoma) had progression-free survival for >1 year, including two who had partial responses. IFN-alpha1b resulted in potent stimulation of IFN-regulated genes and tumor regressions in renal cell carcinoma. Unique gene modulatory effects, when coupled with the moderate severity of side effects and a potentially central role in innate immunity, provide rationale for further clinical evaluation of IFN-alpha1 in virus infections and cancer.

Musculotendon parameters estimation by ultrasound measurement and geometric modeling: application on brachialis muscle

Computational modeling for musculoskeletal system provides quantitative insights in analyzing human movement. One of the major challenges in neuromusculoskeletal modeling is to accurately estimate the musculotendon parameters on subject-specific basis. The ultrasound imaging technology presents a new approach to obtain the parameters in vivo. The pennation angle and fascicle length of brachialis (BRA) were measured in vivo with the use of ultrasonography to investigate the relationship between these muscle architecture parameters and elbow joint position. A generic interactive graphics-based geometrical model of the upper limb and BRA was developed to get the musculotendon length and moment arm of the muscle. The results indicate human brachialis architecture is significantly affected by changing of joint angle at passive horizontal movement. These in-vivo measurements provide subjects-specific information and these muscle parameters can be used to set up the neuromusculoskeletal model for the muscle force and torque estimation.

Proton MR spectroscopy detected glutamate/glutamine is increased in children with traumatic brain injury

Adults with traumatic brain injury (TBI) have been shown by invasive methods to have increased levels of the excitatory neurotransmitter glutamate. It is unclear whether glutamate release contributes to primary or secondary injury and whether its protracted elevation is predictive of a poor outcome. Preliminary studies at our institution in adults found that early increases in magnetic resonance spectroscopy (MRS)-detected glutamate/glutamine (Glx) were associated with poor outcomes. We therefore studied 38 children (mean age, 11 years; range, 1.6-17 years) who had TBI with quantitative short-echo time (STEAM, TE = 20 msec) proton MRS, a mean of 7 +/- 4 (range, 1-17) days after injury in order to determine if their occipital or parietal Glx levels correlated with the severity of injury or outcome. Occipital Glx was significantly increased in children with TBI compared to controls (13.5 +/- 2.4 vs. 10.7 +/- 1.8; p = 0.002), but there was no difference between children with good compared to poor outcomes as determined by the Pediatric Cerebral Performance Category Scale score at 6-12 months after injury. We also did not find a correlation between the amount of Glx and the initial Glasgow Coma Scale score, duration of coma, nor with changes in spectral metabolites, including N-acetyl aspartate, choline, and myoinositol. In part, this may have occurred because, in this study, most patients with poor outcomes were studied later than patients with good outcomes, potentially beyond the time frame for peak elevation of Glx after injury. Additional early and late studies of patients with varying degrees of injury are required to assess the importance to the pathophysiology of TBI of this excitatory neurotransmitter.

[Determination of trace amounts of zinc in nickel electrolyte by flow injection on-line enrichment]

A method for the determination of trace amount of zinc in nickel electrolyte utilizing the flow injection on-line enrichment technique is reported in this paper. Atomic absorption spectrometer was used as detector. Zinc was separated from large amounts of nickel andother components in the electrolyte by absorption its chlorocomplex on a mini-column packed with strongly basic anion exchangers. It was found that sodium chloride containing in the electrolyte offered a sufficient chloride concentration needed for the formation of the zinc chlorocomplex and thus no additional reagent was required for the determination. The throughput of the method is 30 determinations per hour. The detection limit of the method is 0.002 microg x mL(-1) and the precision is 1.9% (RSD). The proposed method is rapid and cost-effective. It has been used for almost three years in the quality control of the electrolyte in the factory with great success.

A practical gait analysis system using gyroscopes

This study investigated the possibility of using uni-axial gyroscopes to develop a simple portable gait analysis system. Gyroscopes were attached on the skin surface of the shank and thigh segments and the angular velocity for each segment was recorded in each segment. Segment inclinations and knee angle were derived from segment angular velocities. The angular signals from a motion analysis system were used to evaluate the angular velocities and the derived signals from the gyroscopes. There was a good correlation between these signals. When performing a turn the signals of segment inclination and knee angle drifted. Two methods were used to solve this: automatically resetting the system to re-initialise the angle in each gait cycle, and high-pass filtering. They both successfully corrected this drift. A single gyroscope on the shank segment could provide information on segment inclination range, cadence, number of steps, and an estimation of stride length and walking speed.

A clinical investigation on massage for prevention and treatment of recurrent respiratory tract infection in children

The TCM therapeutic principle of "eliminating the pathogenic factors by supporting the healthy energy" was adopted in massage to treat and prevent recurrent respiratory tract infection of children. Susceptible and healthy children of the same age were used as controls. As a result, the therapeutic effect of the treatment group is significantly better than that of the controls, with all of the immunologic indexes being approximately normal when the patients were reexamined 3 and 6 months after the massage. Statistically, the difference was significant (P < 0.01). Massage has been proved very helpful in improving the general constitution, enhancing the immune functions, preventing and treating the condition, and in health care as well.

[Treatment and results of N1 supraglottic laryngeal carcinoma]

One hundred and eleven cases of supraglottic squamous cell cancer (T1-4N1) were retrospectively analysed. The result showed that: 1. the 3 years survival rate was 72% (80/111); 2, the rate of contralateral neck node metastasis after ipsilateral RND was 17.9%, and the cases of T3-4 with positive histologic findings of neck dissection samples had a higher rate contralateral neck node metastasis (38.6%); 3, the contralateral neck node metastasis rate (26.1%) in the group with surgery alone was significantly higher than that (7.1%) in the group with preoperative radiation (P < 0.05). The authors draw the conclusion that contralateral neck node metastasis is a high risk factor for recurrence of N1 supraglottic laryngeal cancer and that preoperative radiation may be be useful in controlling subclinical metastasis.

Validity of the McGill Quality of Life Questionnaire in the palliative care setting: a multi-centre Canadian study demonstrating the importance of the existential domain

This study was carried out in eight palliative care services in four Canadian cities. A revised version of The McGill Quality of Life Questionnaire (MQOL) is compared to a single-item scale measuring overall quality of life (SIS), and the self-administered version of the Spitzer Quality of Life Index (SA-QLI), to obtain evidence of validity. MQOL total score predicts SIS better than does SA-QLI, although much of the variance remains to be explained. The results of principal components analysis of data using this revised version of MQOL are similar to those from previous MQOL studies with different patient populations. The MQOL subscales, constructed on the basis of principal components analysis, demonstrate acceptable internal consistency reliability. The MQOL measures reflecting physical well-being and existential well-being are important for predicting SIS.

Steric constraints in the recognition of peptide substrates for the epidermal growth factor receptor kinase

Epidermal growth factor (EGF) stimulates cellular mitogenesis by binding to and activating its membrane-associated receptor. An important component of signal transduction by the activated receptor is the stimulation of an intrinsic tyrosyl residue-specific protein kinase, which selectively phosphorylates tyrosyl residues in the cytoplasmic tail of the receptor and in other cytoplasmic substrates. A recent study utilizing tyrsub, a new high affinity synthetic peptide substrate for the EGF receptor kinase, provided evidence that in peptide substrate binding, the tyrosyl residue plays the central role in recognition, with residues surrounding the tyrosyl residue contributing to stabilization of docking [Guyer et al. (1994) Arch. Biochem. Biophys. 312, 573-578]. A large body of previous work had identified acidic residues near the site of phosphorylation as most important for binding; therefore, other residues in tyrsub appeared to be promising sites for locating spectroscopic reporter groups. Since tyrsub has neutral residues -4 and +4 residues from the site of phosphorylation, we prepared two analogs of tyrsub, in each of which one of those residues was substituted with Cys. These cystyrsubs were found to be effectively phosphorylated by EGF receptor prepared from A431 cells, on stimulation with EGF, with high affinities [Km(app) = 40-50 microM.] Modification of the cystyrsubs with iodoacetamide had no deleterious effect on the ability of the peptide to be phosphorylated by the EGF receptor kinase, while the labeling by 5-iodoacetimidofluorescein completely abolished the productive interaction between the peptide and the EGF receptor. This unexpected failure of the fluorescently labeled peptides to be phosphorylated does, however, provide information on steric limitations to recognition of substrates by the EGF receptor kinase.

Angiotensin II regulates the expression of plasminogen activator inhibitor-1 in cultured endothelial cells. A potential link between the renin-angiotensin system and thrombosis

Plasminogen activator-inhibitor C-1 (PAI-1) plays a critical role in the regulation of fibrinolysis, serving as the primary inhibitor of tissue-type plasminogen activator. Elevated levels of PAI-1 are a risk factor for recurrent myocardial infarction, and locally increased PAI-1 expression has been described in atherosclerotic human arteries. Recent studies have shown that the administration of angiotensin converting enzyme inhibitors reduces the risk of recurrent myocardial infarction in selected patients. Since angiotensin II (Ang II) has been reported to induce PAI-1 production in cultured astrocytes, we have hypothesized that one mechanism that may contribute to the beneficial effect of angiotensin converting enzyme inhibitors is an effect on fibrinolytic balance. In the present study, we examined the interaction of Ang II with cultured bovine aortic endothelial cells (BAECs) and the effects of this peptide on the production of PAI-1. 125I-Ang II was found to bind to BAECs in a saturable and specific manner, with an apparent Kd of 1.4 nM and Bmax of 74 fmol per mg of protein. Exposure of BAECs to Ang II induced dose-dependent increases in PAI-1 antigen in the media and in PAI-1 mRNA levels. Induction of PAI-1 mRNA expression by Ang II was not inhibited by pretreating BAECs with either Dup 753 or [Sar1, Ile8]-Ang II, agents that are known to compete effectively for binding to the two major angiotensin receptor subtypes. These data indicate that Ang II regulates the expression of PAI-1 in cultured endothelial cells and that this response is mediated via a pharmacologically distinct form of the angiotensin receptor.