Exercise knowledge, barriers and motivators among LRRK2 G2019S mutation carriers

INTRODUCTION

People with a Gly2019Ser mutation in the leucine-rich repeat kinase 2 (LRRK2 G2019S) are at increased risk of developing Parkinson's disease (PD). Recent evidence suggests that exercise may delay or prevent the development of clinically overt symptoms of PD in people at risk of PD. We determined whether LRRK2 G2019S mutation carriers with and without manifest PD are aware of the relationship between exercise and PD and how they differ in awareness, barriers and motivators to exercise.

METHODS

We deployed a survey among 4422 LRRK2 G2019S mutation carriers. In total, 505 (11.4%) of them completed the survey, of whom 105 had self-reported manifest PD.

RESULTS

Ninety-two percent of the LRRK2 G2019S mutation carriers with manifest PD and 63% of those with non-manifest PD were aware of the relationship between exercise and PD. Lack of motivation was the top barrier for those without manifest PD, while having an injury/disability was the most common barrier for those with manifest PD. Improvement of body functioning was the top motivator for both.

CONCLUSION

The fact that many at-risk individuals are not aware of the importance of exercise and would exercise more with fewer barriers creates opportunities for trials using exercise as a possible prevention strategy for PD.

Submandibular sialolith migration

A middle-aged male Caucasian had rejected previous offers of surgery for submandibular gland removal in the past due to concerns about surgical complications. He presented with a month's history of submandibular swelling and severe pain, which impeded his ability to eat. Prior to admission, he had been experiencing intermittent sialadenitis for several months. Cross-sectional imaging demonstrated a 16×12 mm migratory sialolith, located superficial to the right submandibular gland within a large loculated abscess. The patient underwent an incision and drainage of the abscess under general anaesthetic and the sialolith was expressed. He was discharged home with oral antibiotics and was followed up as an outpatient. This case serves to highlight a rare complication of chronic sialolithiasis.

Challenge GP: using gamification to bring the reality and uncertainty of a duty doctor's surgery to early year medical students

Exposing medical student cohorts to the lived reality of uncertainty and complexity experienced by GPs is challenging to achieve. We present a novel teaching concept: 'Challenge GP' designed for early years students. Gamification methodology is used to reproduce key elements of the 'duty GP' experience in a classroom setting where working in teams, students play a competitive card game. Cards drawn at random pose scenarios based on practical, logistical, and ethical dilemmas of a duty doctor surgery. Each team discusses whether to score by reporting a decision or play special cards to pass the dilemma onto, or collaborate with, another team. Answers are facilitated and scored by a GP tutor.Student feedback demonstrated highly effective learning for clinical reasoning, risk management and problem-solving. Students were exposed to the uncertainty and complexity of real-life medicine. Gamification, through competitiveness, increased task engagement. Students learned the value of working in teams under time pressure and grew in confidence by sharing knowledge in a safe environment. Students were enabled to think, feel and practise as real-life clinicians. This became a powerful force in contextualising their theory-based knowledge, aided understanding of the GP role and opened their eyes to a possible career in general practice.

Hospital re-admission after critical care survival: a systematic review and meta-analysis

Survivors of critical illness frequently require increased healthcare resources after hospital discharge. We undertook a systematic review and meta-analysis to assess hospital re-admission rates following critical care admission and to explore potential re-admission risk factors. We searched the MEDLINE, Embase and CINAHL databases on 05 March 2020. Our search strategy incorporated controlled vocabulary and text words for hospital re-admission and critical illness, limited to the English language. Two reviewers independently applied eligibility criteria and assessed quality using the Newcastle Ottawa Score checklist and extracted data. The primary outcome was acute hospital re-admission in the year after critical care discharge. Of the 8851 studies screened, 87 met inclusion criteria and 41 were used within the meta-analysis. The analysis incorporated data from 3,897,597 patients and 741,664 re-admission episodes. Pooled estimates for hospital re-admission after critical illness were 16.9% (95%CI: 13.3-21.2%) at 30 days; 31.0% (95%CI: 24.3-38.6%) at 90 days; 29.6% (95%CI: 24.5-35.2%) at six months; and 53.3% (95%CI: 44.4-62.0%) at 12 months. Significant heterogeneity was observed across included studies. Three risk factors were associated with excess acute care rehospitalisation one year after discharge: the presence of comorbidities; events during initial hospitalisation (e.g. the presence of delirium and duration of mechanical ventilation); and subsequent infection after hospital discharge. Hospital re-admission is common in survivors of critical illness. Careful attention to the management of pre-existing comorbidities during transitions of care may help reduce healthcare utilisation after critical care discharge. Future research should determine if targeted interventions for at-risk critical care survivors can reduce the risk of subsequent rehospitalisation.

An innovative and authentic way of learning how to consult remotely in response to the COVID-19 pandemic

Medical students preparing to undertake general practice (GP) placements need to be equipped with the unique skills required to successfully utilise and adapt to current and emerging remote consultation modalities used in primary care and integrate this into their day-to-day clinical practice. Medical educators needed to flexibly and quickly cater learning to the evolving landscape.A three-hour teaching session was devised to be delivered to 50 students online via Microsoft Teams™ and facilitated by five general practice tutors in groups of 10, prior to students' GP placements. In pre-assigned pairs, students undertook two role-play scenarios for the main remote modalities of telephone and video-consultations. E-consultations were explored via discussion of simulated encounters. The authentic technology pertinent to each modality was used; this included a training version of NHS Scotland's Near Me IT platform for video-consultations, the students' own mobile phones for telephone consultations and simulated PDFs generated using the e-consultation facility. Teaching was evaluated via a student focus group pre and post placement.Student feedback was positive. The session prepared them for their placement and increased their confidence. They suggested this teaching be incorporated earlier in the medical school curriculum. They appreciated learning with the same IT platforms used on placement. Some students had no prior experience of remote consultations and subsequently were expected to undertake independent remote consultations almost immediately upon arrival.Careful design of challenging scenarios mirroring common GP presentations via remote modalities can increase student preparedness and confidence prior to GP placements during the COVID-19 pandemic.

Combined neurosurgical and orbital intervention for spheno-orbital meningiomas - the Manchester experience

PURPOSE

Surgical resection of spheno-orbital meningioma (SOM) is challenging, requiring a multidisciplinary surgical approach. We present our experience of the surgical management of patients with SOM.

METHODS

A retrospective analysis of patients with SOM who underwent joint neurosurgical and orbital surgical procedures between January 2000 and June 2017. Pre-operative clinical signs, indication for surgery, surgical complications and post-operative outcomes were recorded.

RESULTS

Twenty-four operations were performed. Mean age was 49.5 years. Ninety-two percent of patients were female. Pre-operatively mean Snellen acuity vision was 6/12; 13 (54%) had an RAPD; 12 (50%) had reduced colour vision; 16 (67%) had a visual field defect. The majority (21 patients, 88%) had proptosis (average 4.5 mm ± 2.8 mm). The indication for surgery was evidence of visual dysfunction in 17 (71%), the remaining 7 (29%) had high risk of visual loss clinically or radiologically. Three-months post operatively, vision was stable in 13 (58%), improved in 6 (21%) and worse in 5 (17%). Average long-term follow-up was 82 months (1-220). Fourteen (58%) maintain improved or stable visual function. Four (17%) had reduced vision due to regrowth of the tumour at an average of 24 months.

CONCLUSION

SOMs are very challenging to treat surgically. In this cohort the patients were predominantly young females with aggressive disease. Visual function was improved or stabilised in 79% of the patients.

Placental SEMA3B expression is not altered in severe early onset preeclampsia

Recent evidence suggests that Semaphorin 3B (SEMA3B) is upregulated in severe preeclampsia, and a major driver of cytotrophoblast aberrations in this disease. Here we independently assess whether SEMA3B expression is altered in a large cohort of severe early onset preeclamptic placentas. We demonstrate that SEMA3B relative mRNA expression and copy number are not changed in PE placentas. We confirm this at the protein level by western blot. Interestingly, exposure of term trophoblasts or explants to hypoxia induced a significant down regulation of SEMA3B mRNA, but a trend towards increased SEMA3B protein expression. We conclude that SEMA3B mRNA and protein is not altered in severe early onset preeclamptic placentas.

First Report of Armillaria Root Disease Caused by Armillaria tabescens on Araucaria araucana in Veracruz, Mexico

In September 2007, bark samples were collected from the root collar of a single Araucaria araucana tree that had recently died and was suspected of being killed by Armillaria root disease. Disease symptoms and signs included a thinning crown and fruiting bodies at the tree base over a several-year period before tree death. The tree was located in an isolated street-tree planting within a business district on Maestros Veracruzanos Street, Xalapa, Veracruz (19°31'52''N, 96°54'25''W, elevation 1,392 m). One fungal isolate (MEX21WF) was obtained, which possessed two sequence repeat types from the intergenic spacer-1 (IGS-1) region (GenBank Accession Nos. GQ335541 and GQ335542). On the basis of these IGS-1 sequences, this isolate from Mexico possessed 99% nucleotide sequence identities with North American Armillaria tabescens isolates (GenBank Accession Nos. AY695410 ≈ GQ335541 and AY773966 ≈ GQ335542). Somatic pairing tests of the isolate with other North American Armillaria species also identified it as A. tabescens (2). In addition, fruiting bodies were produced on the stump base in 2009 that matched morphological features of A. tabescens, e.g., exannulate, cespitose growth in clusters, brown-gray stipe to blackish toward the base, longitudinally fibrillose, basidiospores (6-) 7 to 9 × 4 to 5 (-5.5) μm, and other general morphology. On the basis of these three lines of taxonomic evidence, it was concluded that the isolate was A. tabescens. To our knowledge, this is the first confirmed report of A. tabescens causing Armillaria root disease in Mexico. Furthermore, this note represents the first report of A. tabescens on Araucaria araucana, which is native to Chile and Argentina. The other previous reports of A. tabescens in Mexico are based on herbarium specimens collected in 1965 (BPI 753040) from Valle de Bravo (approximately 350 km west of Xalapa) in the state of México and 1973 (BPI 753041) from near Monterrey (approximately 760 km north-northwest of Xalapa) in the state of Nuevo León (1). However, no host information or confirmation of taxonomic identification was reported for these herbarium specimens. Although this note confirms the presence of A. tabescens in Mexico, more surveys and monitoring are needed to determine the full distribution of this pathogen in Mexico. Because the climate and tree communities of eastern Mexico are similar to those of the southeastern United States, where A. tabescens has been reported as a common pathogen of oaks and fruit trees (3,4), it seems reasonable that A. tabescens may represent an existing or potential threat in eastern Mexico. References: (1) D. F. Farr and A. Y. Rossman. Fungal Databases. Systematic Mycology and Microbiology Laboratory. Online publication. ARS, USDA, 2010. (2) K. I. Mallett and Y. Hiratsuka. Can. J. Bot. 64:2588, 1986. (3) F. Miranda and A. J. Sharp. Ecology 31:313, 1950. (4) G. Schnabel et al. Mycol. Res. 109:1208, 2005.

A Comparison of Infusion Volumes in the Measurement of Intra-Abdominal Pressure

Bladder pressure measurement through a foley catheter is the current standard in monitoring for intraabdominal hypertension (IAH) and abdominal compartment syndrome (ACS). Accurate pressure transduction requires a continuous fluid column with a small volume of transducing medium at the tip of the catheter. Infusing excessive fluid volume can falsely elevate the measured intra-abdominal pressure (IAP) due to bladder overdistention and can lead to intrinsic muscular contraction. This effect can be seen with volumes as low as 60 mL. Recent expert consensus has recommended 25 mL as the maximal infusion volume; however, 50 mL is the most commonly cited volume of infusion in the literature. The purpose of this analysis was to determine the variance between IAP values using a range of volume infusions between 10 and 60 mL. Eighteen adult, surgical intensive care unit (SICU) patients who were undergoing IAP measurement for IAH or clinically indicated monitoring were enrolled in a prospective, nontreatment study. Intra-abdominal pressure measurements were obtained with stepwise increases of injectate volume from 10 to 60 mL (in 10 mL increments). Bland-Altman analyses and receiver operating characteristic (ROC) curves were used for analysis. After analysis accounting for data correlation within patients, means and standard deviations were generated for differences between 50 mL and 10, 20, 30, 40, and 60 mL bladder infusion volumes. Bland-Altman analyses showed good agreement between measurements and no significant difference in variance (mean ≤1.35 mm Hg) between volume comparisons. The ROC curve generated for each test volume using a diagnostic pressure value for IAH (!12 mm Hg) showed that a value between 11 and 12 mm Hg gave the best combination of sensitivity and specificity for all test volumes. In SICU patients, with a clinical indication for IAP monitoring, bladder infusion volumes between 10 mL and 60 mL provide consistent IAP measurements.

Analysis of the acute postoperative pain experience following oral surgery: identification of 'unaffected', 'disabled' and 'depressed, anxious and disabled' patient clusters

BACKGROUND

Pain is defined as both a sensory and an emotional experience. Acute postoperative tooth extraction pain is assessed and treated as a physiological (sensory) pain while chronic pain is a biopsychosocial problem. The purpose of this study was to assess whether psychological and social changes occur in the acute pain state.

METHODS

A biopsychosocial pain questionnaire was completed by 438 subjects (165 males, 273 females) with acute postoperative pain at 24 hours following the surgical extraction of teeth and compared with 273 subjects (78 males, 195 females) with chronic orofacial pain. Statistical methods used a k-means cluster analysis.

RESULTS

Three clusters were identified in the acute pain group: 'unaffected', 'disabled' and 'depressed, anxious and disabled'. Psychosocial effects showed 24.8 per cent feeling 'distress/suffering' and 15.1 per cent 'sad and depressed'. Females reported higher pain intensity and more distress, depression and inadequate medication for pain relief (p < 0.001). Distress and depression were associated with higher pain intensity. The developed questionnaire had tested reliability (test-retest r = 0.89) and estimated validity.

CONCLUSION

Cluster analysis showed constituent groups with a range of psychosocial effects in acute postoperative dental extraction pain and is associated with an increase in pain intensity.

Retroviral vectors bearing IgG-binding motifs for antibody-mediated targeting of vascular endothelial growth factor receptors

Targeting retroviral vectors to tumor vasculature is an important goal of cancer gene therapy. In this study, we report a novel targeting approach wherein IgG-binding peptides were inserted into the Moloney murine leukemia virus (MuLV) envelope (env) protein. The modifications on the viral env included replacement of the entire receptor binding region of the viral env with protein A (or ZZ) domains. The truncated env incorporating IgG-binding motifs (known as proteins) provided the targeting function, while the co-expressed wild-type (WT) env protein enabled viral fusion and cell entry. An anti-human VEGF receptor (Flk-1/KDR) antibody served as a molecular bridge, directing the retroviral vector to the endothelial cell. Hence, the IgG-targeted vectors bound to the Flk-1/KDR antibody which in turn bound to VEGF receptors on Kaposi sarcoma, KSY1, endothelial cells. The net effect was increased viral fusion and infectivity of IgG-bound retroviral vectors when compared to non-targeted vectors bearing WT env alone. These data provide the proof of concept that IgG-binding vector/VEGF receptor antibody complexes may be used to enhance retroviral gene delivery to activated endothelial cells.

Rapid in vivo monitoring of chemotherapeutic response using weighted sodium magnetic resonance imaging

A novel pulse sequence strategy uses sodium magnetic resonance imaging to monitor the response to chemotherapy of mouse xenograft tumors propagated from human prostate cancer cell lines. An inversion pulse suppresses sodium with long longitudinal relaxation times, weighting the image toward intracellular sodium nuclei. Comparing these weighted sodium images before and 24 h after administration of antineoplastics, we measured a 36 +/- 4% (P < 0.001; n = 16) increase in signal intensity. Experiments with these same drugs and cells, treated in culture, detected a significant intracellular sodium elevation (10-20 mM) using a ratiometric fluorescent dye. Flow cytometry studies showed that this elevation preceded cell death by apoptosis, as determined by fluorescent end-labeling of apoptotic nuclei or Annexin V binding. Histopathology on formalin-fixed sections of explanted tumors confirmed that drug administration reduces proliferation (2.2 versus 8.6 mitotic figures per high power field; P < 0.0001), an effect that inversely correlates with the sodium magnetic resonance image response on a tumor-to-tumor basis (P < 0.02; n = 10). Morphological features, such as central zones of nonviable cells, rims of active apoptosis, and areas of viable tumor, could be distinguished by comparing weighted and unweighted images. Advantages of this sodium imaging technique include rapid determination of drug efficacy, improved diagnosis of lesions, ease of coregistration with high resolution proton magnetic resonance imaging, and absence of costly or toxic reagents.

Human placental trophoblasts secrete a disintegrin metalloproteinase very similar to the insulin-like growth factor binding protein-3 protease in human pregnancy serum

During the course of human pregnancy, there is a marked increase in insulin-like growth factor (IGF) binding protein (IGFBP)-3 protease activity in maternal serum that is first evident at 6 weeks of gestation, persists through term, and returns to nonpregnancy levels by day 5 postpartum. This protease activity cleaves IGFBP-3 into smaller fragments that have markedly reduced affinity for the IGFs. To date, the precise identity and cellular origin of the pregnancy-associated serum IGFBP-3 protease have not been established. To investigate whether placental and/or decidual tissues, which uniquely develop during pregnancy, may be sources of the pregnancy-associated serum IGFBP protease, we examined the secretion of IGFBP-3 protease in vitro by isolated human cytotrophoblasts or fibroblasts from second trimester placentae and by in vitro decidualized human endometrial stromal cells. Cytotrophoblasts were either cultured alone, which favors aggregation and fusion, or cocultured with decidualized endometrial stromal cells, which favors differentiation to an invasive phenotype. IGFBP-3 protease activity was detected in trophoblast, but not in placental fibroblast or decidualized endometrial cultures, and was also present in trophoblast-endometrial cocultures. Western ligand blot and Western immunoblot analyses showed that most of the endogenous IGFBP-3 in trophoblast cultures was in the form of low molecular weight fragments with reduced IGF binding affinity. The substrate specificity of the trophoblast-derived protease was identical to that in pregnancy serum, showing activity against IGFBP-2, -3, and -4, but being inactive against IGFBP-1. IGFBP-3 proteolysis by both pregnancy serum and trophoblast conditioned medium showed a major peak of activity at neutral pH. The trophoblast-derived activity caused time-and temperature-dependent proteolysis of IGFBP-3 into fragments of identical size as those produced by pregnancy serum, and also shared its sensitivity to protease inhibitors: highly sensitive to EDTA and o-phenanthroline, partially sensitive to the serine protease inhibitors AEBSF and aprotinin, and insensitive to alpha2-antiplasmin, and to aspartic and cysteine protease inhibitors. IGFBP-3 proteolysis by both pregnancy serum and trophoblast conditioned medium was also insensitive to tissue inhibitor of metalloproteinase-1, precluding the involvement of the matrix metalloproteinases. In contrast, both the pregnancy serum- and trophoblast-derived proteases were preferentially inhibited by a hydroxamic acid derivative with selective activity against the disintegrin-metalloproteinase tumor necrosis factor-alpha converting enzyme. This study shows that placental trophoblasts produce an IGFBP-3 protease with characteristics very similar to the activity found in pregnancy serum and indicates these cells at the maternal-fetal interface are a potential source of the pregnancy-associated serum IGFBP-3 protease. The findings further suggest that the main IGFBP-3 protease activity in both pregnancy serum and trophoblast conditioned medium may correspond to a disintegrin-metalloproteinase type enzyme.

A comparison of guanosine-quartet inhibitory effects versus cytidine homopolymer inhibitory effects on rat neointimal formation

Phosphorothioate oligodeoxynucleotides (PS oligos) manifest antisense and G-quartet aptameric inhibitory effects on vascular smooth muscle cell (SMC) proliferation. PS oligo cytidine homopolymers also have nonsequence-specific, non-G-quartet inhibitory effects on in vitro and in vivo SMC proliferation. In this study, we compared the effects of S-dC18 and S-dC28, 18-mer and 28-mer cytidine homopolymers, respectively, which lack guanosines, with those of ZK10, a G-tetrad forming compound, on in vitro SMC proliferation and in vivo neointimal formation. ZK10 significantly inhibited in vitro human aortic SMC proliferation. At the same molar concentration, ZK10 had significantly greater inhibitory potency on SMC proliferation than either S-dC18, S-dC28, or 7DG-ZK10, which is a modified ZK10 with ten 7-deaza guanosine substitutions. ZK10 was significantly more potent than S-dC18 and S-dC28 in inhibiting PDGF-induced in vitro SMC migration. S-dC18, S-dC28, and ZK10 treatment significantly reduced the intima/media area ratio after rat carotid artery balloon injury compared with the values of the control groups. ZK10 was a more potent inhibitor of neointimal formation than the same chain length S-dC18. ZK10 formed higher-order structures, as shown on gel electrophoresis, in contrast to S-dC28 and 7DG-ZK10. Therefore, the 18-mer ZK10 has comparable in vivo SMC inhibitory effects to the 28-mer S-dC28, a fact that may have ramifications for the development of optimal PS oligos to inhibit angioplasty restenosis.

Metabolic inhibition in the perfused rat heart: evidence for glycolytic requirement for normal sodium homeostasis

Subcellular compartmentalization of energy stores to support different myocardial processes has been exemplified by the glycolytic control of the ATP-sensitive K+ channel. Recent data suggest that the control of intracellular sodium (Nai) may also rely on glycolytically derived ATP; however, the degree of this dependence is unclear. To examine this question, isolated, perfused rat hearts were exposed to hypoxia, to selectively inhibit oxidative metabolism, or iodoacetate (IAA, 100 mumol/l), to selectively inhibit glycolysis. Nai and myocardial high-energy phosphate levels were monitored using triple-quantum-filtered (TQF) 23Na and 31P magnetic resonance spectroscopy, respectively. The effects of ion exchange mechanisms (Na+/Ca2+, Na+/H+) on Nai were examined by pharmacological manipulation of these channels. Nai, as monitored by shift reagent-aided TQF 23Na spectral amplitudes, increased by approximately 220% relative to baseline after 45 min of perfusion with IAA, with or without rapid pacing. During hypoxia, Nai increased by approximately 200% during rapid pacing but did not increase in unpaced hearts or when the Na+/H+ exchange blocker ethylisopropylamiloride (EIPA, 10 mumol/l) was used. Neither EIPA nor a low-Ca2+ perfusate (50 mumol/l) could prevent the rise in Nai during perfusion with IAA. Myocardial function and high-energy phosphate stores were preserved during inhibition of glycolysis with IAA and continued oxidative metabolism. These results suggest that glycolysis is required for normal Na+ homeostasis in the perfused rat heart, possibly because of preferential fueling of Na-K-adenosinetriphosphatase by glycolytically derived ATP.

Overexpression of the matrix metalloproteinase matrilysin results in premature mammary gland differentiation and male infertility

To examine the role of matrilysin (MAT), an epithelial cell-specific matrix metalloproteinase, in the normal development and function of reproductive tissues, we generated transgenic animals that overexpress MAT in several reproductive organs. Three distinct forms of human MAT (wild-type, active, and inactive) were placed under the control of the murine mammary tumor virus promoter/enhancer. Although wild-type, active, and inactive forms of the human MAT protein could be produced in an in vitro culture system, mutations of the MAT cDNA significantly decreased the efficiency with which the MAT protein was produced in vivo. Therefore, animals carrying the wild-type MAT transgene that expressed high levels of human MAT in vivo were further examined. Mammary glands from female transgenic animals were morphologically normal throughout mammary development, but displayed an increased ability to produce beta-casein protein in virgin animals. In addition, beginning at approximately 8 mo of age, the testes of male transgenic animals became disorganized with apparent disintegration of interstitial tissue that normally surrounds the seminiferous tubules. The disruption of testis morphology was concurrent with the onset of infertility. These results suggest that overexpression of the matrix-degrading enzyme MAT alters the integrity of the extracellular matrix and thereby induces cellular differentiation and cellular destruction in a tissue-specific manner.

Cytokine control of interstitial collagenase and collagenase-3 gene expression in human chondrocytes

Human collagenase-3 expression, previously seen only in a breast tumor tissue, is here shown to be expressed in primary human chondrocytes derived from the joint tissue and in transformed human chondrocytes. Its mRNA is inducible by the inflammatory cytokines interleukin-1beta plus tumor necrosis factor-alpha, but not by phorbol 12-myristate 13-acetate and only slightly by the growth factors platelet-derived growth factor and epidermal growth factor. Human synovial fibroblasts, another prominent cell type in the joint tissue, do not produce collagenase-3 message. Expression of the murine collagenase, which is possibly the counterpart of human collagenase-3, is induced by interleukin-1beta plus tumor necrosis factor-alpha, and its full induction requires the presence of the transcription factor, c-FOS. This family of transcription factors also plays a role in induction of human collagenase-3, since it binds to the AP-1 site of this matrix metalloproteinase.

Human endometrial matrix metalloproteinase-2, a putative menstrual proteinase. Hormonal regulation in cultured stromal cells and messenger RNA expression during the menstrual cycle

Proteinases are likely effectors of endometrial menstrual breakdown. We have investigated proteinase production by human endometrial stromal cells subjected in vitro to progesterone (P) withdrawal, the physiologic stimulus for menstruation. Culture media of cells exposed to estradiol, P, or estradiol plus P had low levels of proteolytic activity similar to cultures maintained in the absence of steroids. P withdrawal, or addition of RU486 to P-treated cultures, stimulated proteinase secretion. The stromal cell proteinase was characterized by gelatin zymography, inhibitor profile, and organomercurial activation, as a metalloproteinase present mostly as a 66-kD proenzyme with lower levels of a 62-kD active form. The P withdrawal-induced metalloproteinase was identified as matrix metalloproteinase-2 (MMP-2) by Western blotting. The increase of MMP-2 induced by P withdrawal was associated with the metalloproteinase-dependent breakdown of stromal cultures, involving dissolution of extracellular matrix and dissociation of stromal cells. Northern analysis showed the differential expression of MMP-2 mRNA in late secretory phase endometrium. These findings are consistent with the involvement of stromal cell-derived MMP-2 in the proteolysis of extracellular matrix promoting cyclic endometrial breakdown and the onset of menstrual bleeding.

Victim as offender in youth violence

STUDY OBJECTIVE

To determine how often adolescent and young adult victims of assaultive injury are offenders in assaults and other crimes.

DESIGN

Comparison of 10- to 24-year-old males treated in the accident and emergency department for assault-related injuries to similar-aged males treated in the same department for unintentional injuries. Police records were searched on both groups for warnings or convictions.

SETTING

Accident and emergency department of the Cardiff Royal Infirmary.

RESULTS

Assault patients were significantly more likely to be formally warned or convicted, and they had a higher mean number of warnings or convictions per 100 person-years of exposure, than other injury patients. These differences were most pronounced for the younger patients and for the year following the injury.

CONCLUSION

These results suggest that many young male assault patients either have a history of criminal activity or develop criminal behavior subsequent to their assault and may benefit from appropriate intervention aimed at interrupting the cycle of crime and violence.

The economics of orphan drug policy in the US. Can the legislation be improved?

This review of the US Orphan Drug Act (ODA) 1983 outlines how the ODA is intended to stimulate orphan drug research and development of drugs for rare diseases. We also evaluate the effectiveness of the ODA in the past decade and provide recommendations for ODA improvements in the future. The economic incentives embedded in the ODA are presented in a simple economic model, in which a guarantee of market exclusivity plays a central role in encouraging firms to pursue the development of orphan products. Some evidence suggests that this provision has been a major impetus for the rise in orphan drug applications and designations in the last decade. Market exclusivity is the key incentive for orphan drug research, and should be retained. Concerns about a limited number of highly successful 'blockbuster' orphan drugs should be evaluated in terms of the useful economic incentives. In the future, exceptionally high profits could be limited by more precise evaluation of disease prevalence, elasticity of demand, and the other uses of orphan compounds. We further recommend an expansion of the ODA tax credits and research grants programme and targeting of 'priority' diseases. We conclude that the ODA has been a valuable legislative initiative, but it can be strengthened with some simple extensions of the current incentives that it contains.

A new immunohistochemical antibody for the assessment of estrogen receptor status on routine formalin-fixed tissue samples

We describe a method for the immunocytochemical assessment of estrogen receptor (ER) status on routinely processed, formalin-fixed tissue using a recently developed commercially available monoclonal antibody (Dako 1D5) with a microwave antigen retrieval technique. A series of 90 cases of human breast carcinoma was analyzed and the staining was assessed using a semiquantitative microscopic scoring method and by assessment of the percentage of nuclei showing positive staining. The results were compared with assessment using another commercially available antibody (Abbott H222) and with clinical response to tamoxifen therapy. Direct comparison of the paired sets of H scores and the percentage of positively stained nuclei using the two different techniques showed a significant correlation. By assigning an arbitrary cut-off for positivity of H score = 50, assessment of ER status using DAKO 1D5 antibody was found to correlate with response to tamoxifen therapy with a sensitivity of 90% and a specificity of 51%, similar to values in previous studies using other methods. We conclude that assessment of ER status using this new antibody and technique gives accurate results on routinely processed, formalin-fixed tissue and may be used as an alternative to other methods.

Modulation of matrilysin levels in colon carcinoma cell lines affects tumorigenicity in vivo

The expression of the metalloproteinase matrilysin in the human colon carcinoma cell lines SW480 and SW620 correlates with the ability of the SW620 cells to invade an artificial basement membrane in vitro and metastasize to the liver following injection into the cecum of nude mice in vivo. Transfection of either wild-type or activated forms of matrilysin into the SW480 cells, which do not express endogenous matrilysin, did not reproducibly increase in vitro invasion but increased the tumorigenicity of the cells when injected into the cecum of nude mice. Antisense reduction of matrilysin levels decreased the tumorigenicity of the SW620 cells and subsequent metastasis to the liver. These results suggest that matrilysin gene expression by colon adenocarcinoma cells is not sufficient for tumor invasion and metastasis but contributes to the tumorigenicity and progression of colorectal tumors.

Patterns of matrix metalloproteinase expression in cycling endometrium imply differential functions and regulation by steroid hormones

Matrix metalloproteinases are a highly regulated family of enzymes, that together can degrade most components of the extracellular matrix. These proteins are active in normal and pathological processes involving tissue remodeling; however, their sites of synthesis and specific roles are poorly understood. Using in situ hybridization, we determined cellular distributions of matrix metalloproteinases and tissue inhibitor of metalloproteinase-1, an inhibitor of matrix metalloproteinases, in endometrium during the reproductive cycle. The mRNAs for all the metalloproteinases were detected in menstrual endometrium, but with different tissue distributions. The mRNA for matrilysin was localized to epithelium, while the others were detected in stromal cells. Only the transcripts for the 72-kD gelatinase and tissue inhibitor of metalloproteinases-1 were detected throughout the cycle. Transcripts for stromelysin-2 and the 92-kD gelatinase were only detected in late secretory and menstrual endometrium, while those for matrilysin, the 72-kD gelatinase, and stromelysin-3 were also consistently detected in proliferative endometrium. These data indicate that matrix metalloproteinases are expressed in cell-type, tissue, and reproductive cycle-specific patterns, consistent with regulation by steroid hormones, and with specific roles in the complex tissue growth and remodeling processes occurring in the endometrium during the reproductive cycle.

Transforming growth factor-alpha and endocrine sensitivity in breast cancer

The expression of transforming growth factor-alpha (TGF-alpha) has been evaluated in 51 breast cancers of known responsiveness to endocrine therapy using immunohistochemistry. High levels of TGF-alpha were observed in 65% of tumors and showed no relationship with tumor estrogen receptor or epidermal growth factor receptor status or Ki67 immunostaining. TGF-alpha levels did, however, relate to the endocrine sensitivity of the disease, with unresponsive tumors frequently showing high levels of TGF-alpha immunoreactivity. This relationship was observed in estrogen receptor-positive disease and was independent of the epidermal growth factor receptor status of the tumor. No quantitative association between TGF-alpha and Ki67 immunostaining was observed in any of the subcategories of tumors. These data infer a role for TGF-alpha in the development of endocrine insensitivity in estrogen receptor-positive breast cancer by mechanisms which appear independent of tumor growth fraction, as determined by Ki67 immunostaining.

Analysis of Tat function in human immunodeficiency virus type 1-infected low-level-expression cell lines U1 and ACH-2

The U1 and ACH-2 cell lines are subclones of human monocytic and T-lymphoid cells, respectively, persistently infected with human immunodeficiency virus type 1. These cell lines harbor the viral genome but produce only very low levels of viral progeny, which can be increased by stimulation with agents such as phorbol ester and cytokines. As such, they provide an in vitro model for human immunodeficiency virus type 1 latency. In order to examine the basis for their latent state, we have analyzed the activity of endogenous Tat protein in these cells and investigated the effect on viral replication of the addition of exogenous Tat protein. We find that U1 cells seem to have levels of Tat protein that are suboptimal for long terminal repeat (LTR) transcription, because transcription from a transfected LTR-chloramphenicol acetyltransferase plasmid can be enhanced by cotransfection of a Tat expression plasmid. Furthermore, viral replication can be stimulated in this cell line by incubation with purified Tat protein. In contrast, ACH-2 cells are not limited for LTR-chloramphenicol acetyltransferase transcription by endogenous levels of Tat, and virus production is not increased by the addition of exogenous Tat protein. By semiquantitative PCR analysis of viral RNA, we have demonstrated that Tat protein caused an increase in human immunodeficiency virus RNA expression in U1 cells but had no effect in ACH-2 cells. This suggests that a different mechanism underlies the latent state in U1 and ACH-2 cells.

Inhibition of human immunodeficiency virus type 1 Tat-dependent activation of translation in Xenopus oocytes by the benzodiazepine Ro24-7429 requires trans-activation response element loop sequences

Two benzodiazepine compounds, [7-chloro-5-(2-pyrryl)-3H-1,4 benzodiazapin-2-(H)-one] (Ro5-3335) and [7-chloro-5-(1H-pyrrol-2-yl)-3H-benzo[e] [1,4] diazepin-2-yl]- methylamine (Ro24-7429), inhibit human immunodeficiency virus type 1 (HIV-1) replication via a specific effect on the function of the transactivator protein, Tat. To gain further insight into the mechanism of action of these compounds, we have tested their effects in an alternative assay for Tat activation in Xenopus oocytes. In this system, translation of trans-activation response element (TAR)-containing RNA is activated by Tat. Both compounds specifically blocked activation of translation in a dose-dependent fashion, with Ro24-7429 showing the greater potency. In the Xenopus oocyte system, as in mammalian cells, mutation of the TAR loop sequences abolishes Tat action. However, it is possible to obtain TAR-specific, Tat-dependent activation of a target RNA with a mutation in the loop provided that this target is in large excess. This result has been interpreted as indicating that a negative factor has been titrated (M. Braddock, R. Powell, A.D. Blanchard, A.J. Kingsman, and S.M. Kingsman, FASEB J. 7:214-222, 1993). Interestingly Ro24-7429 was unable to inhibit the TAR-specific but loop sequence-independent mode of translational activation. This finding suggests that a specific loop-binding cellular factor may mediate the effects of this inhibitor of Tat action. Consistent with this notion, we could not detect any effect of Ro24-7429 on the efficiency of specific Tat binding to TAR in vitro.

Epidermal growth factor receptor expression in breast cancer: association with response to endocrine therapy

106 previously untreated breast cancer patients have been immunohistochemically analysed for EGF-R, ER, Ki67, and c-erbB-2 product. All patients received assessable endocrine therapy following disease progression. Significant associations were observed between EGF-R and ER (inverse) and Ki67 (direct). No association was observed between EGF-R and the c-erbB-2 product. EGF-R expression was significantly associated with the loss of endocrine sensitivity in breast cancer. This was observed in both ER positive and negative disease. In ER positive breast cancers, EGF-R expression had no significant influence on the quality of tumour remissions. Further sub-classification of the ER/EGF-R data by Ki67 immunostaining showed that in ER+/EGF-R-disease, increasing proportions of Ki67 positive cells were associated with a decline in the numbers of women experiencing good quality tumour remissions. A similar trend was also observed in ER+/EGF-R+ tumours. The presence of c-erbB-2 protein product did not influence endocrine sensitivity in any of the ER/EGF-R sub-groups.

Oestrogen-regulated genes in breast cancer: association of pLIV1 with lymph node involvement

In order to isolate markers of oestrogen responsiveness in breast cancer, we have cloned a number of oestrogen-regulated genes. Two of these, pLIV1 and pLIV2 (pS2), have been shown to be predominantly expressed in oestrogen receptor (ER)+ tumours. In this study, we examined their expression in relation to various clinical and histopathological features of breast cancer, and showed that pLIV1, but not pS2, is significantly associated with lymph node involvement (P < 0.01), while pS2 is more frequently observed in premenopausal patients (P < 0.05). Subdivision of the pLIV1 data by ER and nodal status of the tumour identified a highly significant association between pLIV1 expression and lymph node involvement in ER-positive disease, with 15/24 (63%) ER+ pLIV1+ tumours showing nodal involvement. Conversely, 20/23 (87%) ER+ pLIV1- patients were lymph node-negative (P < 0.001). Subdivision of the pS2 data by ER status did not reach significance. The application of pLIV1 as a marker of lymph node involvement was further exemplified in small tumours (< < 2 cm), where 11/12 (92%) lymph node-positive patients expressed pLIV1, while 17/22 (77%) node-negative patients were pLIV1 negative (P < 0.001). Similarly, pLIV1 expression identified lymph node involvement in moderately differentiated tumours (P < 0.01), but was independent of vascular invasion. pLIV1 may, therefore, represent a candidate gene for metastatic spread in ER+ breast cancer.

Reduced expression of AP27 protein, the product of a growth factor-repressible gene, is associated with diminished adipocyte differentiation

We have recently characterized an adipocyte cDNA (clone 5) that is enhanced in expression by environmental and hormonal conditions favoring adipogenic differentiation. Moreover, certain agents including fibroblast growth factor and phorbol 12-myristate 13-acetate (but not epidermal growth factor) markedly inhibit clone 5 gene expression and prevent TA1 cell differentiation. These results led us to propose that a threshold level of the clone 5 gene product (AP27 protein) is required for triggering adipocyte differentiation. We have constructed vectors that direct the synthesis of clone 5 antisense RNA to reduce the levels of AP27 in adipogenic cell lines TA1 and 3T3-L1. We show here that when these cells express clone 5 antisense RNA, they fail to undergo morphological differentiation, whereas adipogenesis is unaffected in cells expressing antisense beta-actin or ferritin heavy-chain RNA. We further show that cells expressing clone 5 antisense RNA (but not the other antisense RNAs) are unable to induce the expression of characteristic "adipocyte-specific" mRNAs. The level of inhibition of differentiation by clone 5 antisense RNA correlates with decreased levels of AP27 protein. These results provide strong evidence that expression of AP27 is linked to adipogenic differentiation and that AP27 may be a component of an as-yet-uncharacterized signal-transduction pathway required for the triggering of adipocyte differentiation.

Nifedipine in the treatment of hypertension

Nifedipine, a calcium antagonist with a predominant vasodilator action, was evaluated for the treatment of hypertension. A 20 mg-tablet, with a slower absorption and a more sustained blood-level than provided by the 10 mg-capsule was administered to 20 patients. The duration of the trial was 20 weeks. All patients achieved a significant reduction in both systolic (p less than 0.05) and diastolic (p less than 0.001) blood-pressure (B.P.), but 10 patients were withdrawn before completion of the trial period. Two patients, although achieving a fall in B.P. which was significant, did not reach to target level (less than 160/90) on maximal dosage, one patient suffered a stroke due to a cerebral infarct, and seven patients were withdrawn because of side-effects due mainly to vasodilatation. The remaining 10 patients obtained a satisfactory response. In nine patients, who had achieved a satisfactory result, there was no change in plasma renin activity (P.R.A.) during chronic nifedipine administration.

Administering the contract

Administering the collective bargaining contract is a challenging and important nursing administration responsibility. This article discusses the attitudes, skills, and strategies that the nursing administrator who manages a unionized professional staff can use to minimize employee grievances and foster a professional practice climate. Directors of nursing in nonunionized settings also can use these guidelines to maintain the union-free status of their departments.

Glucagon as a hypotonic agent in cholangiography

The effects of Glucagon on 35 cholangiographic studies was examined. Relief of spasm at the choledochoduodenal sphincter resulted in consistently improved demonstration of this area. Diminished spasm-induced pain was also recorded. The use of intravenous Glucagon is recommended for cholangiographic studies where there is total biliary obstruction, or where there is unsatisfactory demonstration of the choledocho-duodenal area.