Comparison of home-based palliative care delivered by community health workers versus usual care: research protocol for a pilot randomized controlled trial

BACKGROUND

Research studies demonstrate that palliative care can improve patient outcomes such as quality of life, symptom burden and patient satisfaction with care (Gomes B, et al. Effectiveness and cost-effectiveness of home palliative care services for adults with advanced illness and their caregivers. Cochrane Database Syst Rev. 2013(6):CD00776) (World Health Organization. Palliative Care. Published 2020.). While 76% of patients who need palliative care live in limited-resource countries, access to high quality palliative services in these countries is minimal (Worldwide Hospice and Palliative Care Association and World Health Organization. Global Atlas of Palliative Care (2nd ed). 2020.). In 2014 the Worldwide Hospice Palliative Care Alliance, with strong endorsement by the WHO, released the Palliative Care Toolkit to provide a training and implementation toolkit for empowering community members to deliver palliative care in resource poor settings (Worldwide Hospice and Palliative Care Association and World Health Organization. Global Atlas of Palliative Care at the End of Life. Geneva, Switzerland 2014.). They encouraged researchers and public health practitioners to conduct rigorous evaluation of the toolkit in diverse settings and contexts. To address this need, we will conduct a pilot randomized controlled trial (RCT) to examine implementation and explore potential effect of an intervention based upon the Palliative Care Toolkit, as adapted and used by community health workers (CHWs) working with a cancer center in Kolkata, India to deliver home-based palliative care for rural patients.

METHODS

Utilizing a randomized controlled trial design, intervention patients (n = 45) receive home-based palliative services (Pal-Care) delivered by community health workers (CHWs), with comparison against a control group of patients (n = 45) who receive usual cancer-center-based palliative services. Primary outcome measures include evaluation of CHW training outcomes, roles and responsibilities of the CHWS and how they assist patients, trial recruitment, stakeholder perceptions of the intervention, and fidelity to study protocol. Secondary outcomes measure patient self-report of health-related quality of life, symptom burden, palliative needs and patient care experience, outcomes The RE-AIM framework guides our evaluation plan to measure the reach, effectiveness, adoption, implementation and maintenance of the Pal-Care intervention (Gaglio B, et al. The RE-AIM framework: a systematic review of use over time. Am J Public Health. 2013;103(6):e38?46.). Data will be analyzed in SAS. All measures will be evaluated overall and by patient age, gender and cancer type and by CHW caseload.

DISCUSSION

Pal-Care is a RCT funded by the NCI to explore utilization of CHWs to deliver a home-based palliative care intervention built upon the WHO Palliative Care toolkit (PCT), as compared to a usual care control group. The long-term goal of this research is to develop an effective and sustainable model for delivering home-based palliative care for cancer patients in underserved areas.

TRIAL REGISTRATION (TRN)

ClinicalTrials.gov ID# NCT04972630.

The denture microbiome in health and disease: an exploration of a unique community

The United Nations suggests the global population of denture wearers (an artificial device that acts as a replacement for teeth) is likely to rise significantly by the year 2050. Dentures become colonized by microbial biofilms, the composition of which is influenced by complex factors such as patient’s age and health, and the nature of the denture material. Since colonization (and subsequent biofilm formation) by some micro‐organisms can significantly impact the health of the denture wearer, the study of denture microbiology has long been of interest to researchers. The specific local and systemic health risks of denture plaque are different from those of dental plaque, particularly with respect to the presence of the opportunist pathogen Candida albicans and various other nonoral opportunists. Here, we reflect on advancements in our understanding of the relationship between micro‐organisms, dentures, and the host, and highlight how our growing knowledge of the microbiome, biofilms, and novel antimicrobial technologies may better inform diagnosis, treatment, and prevention of denture‐associated infections, thereby enhancing the quality and longevity of denture wearers.

Design of a 16-channel fiber-optic coupled radiation detection array for radiation asymmetry studies in a 750-kJ dense plasma focus

A 16-channel fiber optically coupled radiation detection array has been developed for studies of radiation asymmetries and emission histories from the Verus Research 750-kJ Dense Plasma Focus. Each detector in the array consists of a light-tight housing with a plastic scintillator coupled to a fiber optic that is fed into one channel of a multi-anode photomultiplier tube (PMT). The PMT and associated electronics are located in a remote electrically shielded control room. The detector head is configurable for using a Be-9 foil to take advantage of the ⁹Be(n,α)⁶He reaction as a fast neutron activation detector or with a bare scintillator alone to record the radiation emission history. Fiber optically coupling the detector head not only provides electrical isolation in the pulsed power environment but also allows the spatial footprint of the detector array to be reduced with concomitant flexibility in positioning each individual detector head. The array allows for spatially resolved neutron yield and radiation waveform measurements for fast z-pinches. The activation detector heads were calibrated for the total neutron yield against silver and indium activation counters for the total neutron yield. Fiber scintillation was found to contribute to the time-resolved detector head signals and was accounted for.

Efficacy of cardiopulmonary resuscitation in the supine position with manual displacement of the uterus vs lateral tilt using a firm wedge: a manikin study

Prevention of aortocaval compression is essential for effective cardiopulmonary resuscitation in late pregnancy. This can be achieved by either lateral maternal tilt or lateral uterine displacement. Results from a previous manikin study show that a firm foam-rubber wedge allowed successful chest compressions whilst providing stable and reliable lateral tilt. However, it did not investigate resuscitation in the supine position with manual uterine displacement. The aim of this study was to compare the effectiveness of chest compressions in a manikin in the supine position vs lateral tilt using a foam-rubber wedge, both on the floor and on a typical patient bed. Overall, we found that compressions were easier to perform in the supine position (p = 0.007 (bed) and 0.048 (floor)), and with greater stability in the supine position on the floor (p = 0.011). The effectiveness of chest compressions was similar in both the supine/uterine displacement and the lateral tilt positions, suggesting that either method may be suitable for CPR.

Pregnant women's views on informed consent for research in labour

BACKGROUND

Studies of the optimal treatment of accidental dural puncture occurring during epidural insertion in labour are difficult for practical reasons and because of the ethical issues around seeking consent. In a recent study of accidental dural puncture, participants were assigned to one of two treatment groups and only informed about the study and consent sought, after treatment. We sought the views of parturients on the timing of consent for such a study.

METHODS

After ethical approval and written consent, 100 nulliparous women in the third trimester of pregnancy completed a structured, facilitated questionnaire, rating the acceptability of the consent process occurring: (i) in antenatal clinic; (ii) after the epidural was requested in labour; (iii) after the accidental dural puncture had occurred but before treatment; (iv) after the allocated treatment; or (v) without consent (waived consent). Results were analysed with the Friedman and Wilcoxon signed-rank tests.

RESULTS

Antenatal consent was considered the most acceptable option, whilst consent on request for epidural analgesia and after accidental dural puncture were least acceptable. Consent after treatment and waived consent were rated in-between these extremes. There was a statistically significant difference between these three groups (P<0.0001). There was a wide range of opinions on each option presented.

CONCLUSIONS

Antenatal consent was the preferred option but if this is not possible and the need for the research is strong, consent for the use of women's data after intervention, or waived consent, is acceptable to many women. It is important to seek the views of the participants themselves before planning research with difficult ethical aspects.

Handling the sequelae of breast cancer treatment: use of NPWT to enhance patient independence

A cancer diagnosis can be an overwhelming experience and has devastating implications for an individual, their family and friends. Radical treatment, although often essential, can have its own health consequences. This case study describes the management of a 38-year-old woman with a portable, non-electrical negative pressure wound therapy device, suggesting benefits in terms of healing, patient independence and improved quality of life. The case study also highlights the importance of effective communication, patient involvement and empowerment in clinical decision-making, showing that an effective client-clinician relationship can help overcome the physical and emotional sequelae of this diagnosis.

Current views on the functions of interleukin-17A-producing cells in atherosclerosis

Multiple components of the immune response are involved in the initiation, progression and persistence of atherosclerosis. Interleukin (IL)-17A is produced by a broad variety of leukocytes and plays an important role in host defense. IL-17A is also involved in the pathology of several autoimmune diseases mainly via the regulation of chemokine expression and leukocyte migration to the site of inflammation. There is an increasing body of evidence indicating an association between elevated levels of IL-17A and cardiovascular diseases. Interestingly, this IL-17A-dependent response occurs in parallel with the Th1-dominant immune response during atherogenesis. To date, the precise role of IL-17A+ cells in atherosclerosis is controversial. Several studies have suggested a pro-atherogenic role of IL-17A via the regulation of aortic macrophage numbers, Th1-related cytokines and aortic chemokine expression. However, two studies recently described anti-inflammatory effects of IL-17A on mouse plaque burden via possible regulation of aortic VCAM-1 expression and T cell content. Furthermore, an initial study using IL-17A-deficient mice demonstrated that IL-17A affects the immune composition and inflammatory phenotype of the aortic wall; however, no effects were observed on atherosclerosis. Further studies are necessary to fully address the role of IL-17A and other IL-17 family members in atherosclerosis.

Altered autoimmune response in NOD-Alox15null mice (99.13)

12/15-lipoxygenase (12/15-LO) reacts with fatty acids to produce pro-inflammatory lipids, enhance IL-12 production by macrophages (MΦ), and its product 12-(S)-HETE induces pancreatic β-cell apoptosis at nM concentrations. Congenic NOD mice deficient in 12/15-LO (NOD-Alox15null) show a significant decrease in Type 1 diabetes (T1D) development (2.5 vs. &gt;60% in ♀ by 30 wks). We tested the effects of the deficiency on the immune system in NOD-Alox15null vs. NOD mice. Adoptive transfer of diabetic (diab) or non-diabetic (non-diab) NOD, and non-diab NOD-Alox15null splenocytes (cells) determined ability of T1D disease transfer in NOD.scids. Both diab and non-diab NOD cells conferred T1D in NOD.scid hosts, but non-diab NOD-Alox15null cells did not (&gt;8 wks post-transfer). NOD-Alox15null.scids were also injected with either NOD (diab and non-diab) or NOD-Alox15null (non-diab) cells. NOD cells still transferred disease, but NOD-Alox15null cells did not. As transferred splenocytes were mainly T and B cells, we tested for 12/15-LO mRNA expression in these subsets. 12/15-LO levels were minimally detectable, suggesting that immune effects are likely due to indirect effects on B and T cells. To study the mechanism, we looked at the role of 12/15-LO on APCs. Fewer MΦ infiltrate the pancreas of NOD-Alox15null mice at 4 wks of age compared to NOD controls. Also, MΦ from 10-wko NOD-Alox15null mice show reduced IL-12 expression compared to age-matched NODs. Therefore, 12/15-LO is a key regulator of the autoimmune response leading to T1D.

Laser vs ultrasound biometry—a study of intra- and interobserver variability

BACKGROUND

Accurate biometry is of vital importance in achieving predictable postoperative refraction following cataract surgery.

AIM

To evaluate the accuracy and consistency in biometry, achieved by the new generation laser biometric system in comparison with the ultrasound biometric system.

METHODS

The study was randomized and prospective. Biometry was performed in 68 eyes of 39 patients by three groups of biometrists (expert, intermediate user, novice). Expert and intermediate users are compared as group A, and expert and novice are compared in group B. Axial length, anterior chamber depth (ACD), and keratometry results are compared by t-test analysis.

RESULTS

Axial length measurement variation between expert and non experts was 10 times less using laser than ultrasound (P<0.001). ACD measurement variation was also significantly less when using laser compared to ultrasound (P=0.003). Need for some level of user training is indicated in ACD measurement since group A achieved more consistent readings than group B. Keratometry measurements on the laser system were unreliable due to high range of results. Biometric failure was seen in 12% of eyes undergoing laser and 1% undergoing ultrasound biometry.

CONCLUSION

Axial length determination by laser biometry is more accurate and consistent at all levels of biometrist expertise, compared to ultrasound biometry. ACD and keratometry measurements on the laser systems need some degree of user training in order to produce consistent results.

Comparison between standard Goldmann applanation prism and disposable applanation prism in tonometry

BACKGROUND

Disposable devices are increasingly becoming the preferred choice where possible in contact medical equipment.

AIM

To evaluate the accuracy of the disposable applanation tonometer head as a potential substitute to the standard Goldmann applanation head.

METHODS

The study was prospective. The intraocular pressure recordings in 80 eyes of 42 patients were compared using the disposable and standard Goldmann applanator heads. The Bland and Altman method of assessing agreement between two methods of clinical measurement was used in the analysis.

RESULTS

The difference in the readings between the two types of tonometer heads was highly variable (mean difference=0.78 mm Hg, range=-1 to 11 mm Hg). This was because of the distortions on the applanating surface of the disposable device. When the readings associated with the defective heads were excluded, very strong agreement was obtained (mean=0.07 mm Hg, range=-1 to 2 mm Hg).

CONCLUSION

Good agreement with standard Goldmann applanation is achieved with the disposable heads except where surface distortions induce significant errors. Careful inspection to ensure well-structured disposable units is imperative in disposable applanation tonometry.

Driving ability after pupillary dilatation

BACKGROUND

The Royal College of Ophthalmologists' guidelines and Driver and Vehicle Licensing Agency (DVLA) recommend that a patient should not drive with dilated pupils based on the rationale that vision may be compromised in acuity and ability to tolerate glare. Arguments exist against these recommendations suggesting that pupillary dilatation does not have any real bearings on driving ability. Aim To determine the effects of pupillary dilatation on the ability to drive.

METHODS

The study was randomised and prospective. A total of 28 patients had their visual parameters (distance vision, near vision, licence plate reading at 20 m or shorter, and glare) measured and analysed pre- and post-tropicamide 1% dilatation. Paired two-tailed Student's t-test and chi(2)-test were used in the analysis.

RESULTS

At 20 min, following instillation of one drop of tropicamide 1% there is a significant reduction in visual acuity (VA), for distance Snellen and near. There is a significant reduction in the number of people who could read the licence plate at 20 m. Subjective glare assessment changed from 'none' (average score) in the undilated state to 'mild' in the dilated states. The overall patient feedback indicated that a significant 14% believed they would find it difficult to drive postdilatation.

CONCLUSION

This study demonstrates the rationale behind disallowing driving following pupillary dilatation. The risks to safe driving are proved significant as a result of significant reduction in visual quality and quantity after dilatation.

Post-surgery vaginal packs

The editor welcomes readers' questions and alternative answers to questions and letters.These should be sent to the Journal of Wound Care, Greater London House, Hampstead Road, London NW1 7EJ. Fax: +44 (0)20-7874 0386. Email: jwc@emap.com

Experimental inoculation of domestic cats (Felis domesticus) with Sarcocystis neurona or S. neurona-like merozoites

Sarcocystis neurona is the parasite most commonly associated with equine protozoal myeloencephalitis (EPM). Recently, cats (Felis domesticus) have been demonstrated to be an experimental intermediate host in the life cycle of S. neurona. This study was performed to determine if cats experimentally inoculated with culture-derived S. neurona merozoites develop tissue sarcocysts infectious to opossums (Didelphis virginiana), the definitive host of S. neurona. Four cats were inoculated with S. neurona or S. neurona-like merozoites and all developed antibodies reacting to S. neurona merozoite antigens, but tissue sarcocysts were detected in only two cats. Muscle tissues from the experimentally inoculated cats with and without detectable sarcocysts were fed to laboratory-reared opossums. Sporocysts were detected in gastrointestinal (GI) scrapings of one opossum fed experimentally infected feline tissues. The study results suggest that cats can develop tissue cysts following inoculation with culture-derived Sarcocystis sp. merozoites in which the particular isolate was originally derived from a naturally infected cat with tissue sarcocysts. This is in contrast to cats which did not develop tissue cysts when inoculated with S. neurona merozoites originally derived from a horse with EPM. These results indicate present biological differences between the culture-derived merozoites of two Sarcocystis isolates, Sn-UCD 1 and Sn-Mucat 2.

Collecting pressure ulcer prevention and management outcomes: 2

The first part of this article (Vol 11(4): 230-8) outlined the argument that a combination of efficacy and effectiveness is required to assess fully the impact of interventions such as pressure-redistributing (PR) beds and mattresses. In addition, it described the methodology of this multinational, multicentre, prospective, non-randomized cohort study designed to record the occurrence and characteristics of patients vulnerable to, or with, established pressure ulcers. This article reports further details of the characteristics of the 2507 UK adult hospital patients recruited to the study. Over 40% (42% n = 1046) of all subjects were considered to be at an elevated risk of developing ulcers (Waterlow score of 15 or greater) (Waterlow, 1985). Many were inactive with 332 (13%) confined to bed alone with a further 262 (10%) confined to bed and their chair. Most (74% n = 1868) were nursed upon PR beds and mattresses, while fewer subjects were provided with a PR seat cushion (n = 547; 27%). Two hundred and fifty-seven subjects (10%) experienced at least one change of bed mattress during their stay in hospital, with two subjects being nursed on five different mattresses during their hospital stay.

Collecting pressure ulcer prevention and management outcomes: 1

This article, the first of two parts, presents the argument that a combination of efficacy and effectiveness is required to assess fully the impact of interventions such as pressure-redistributing beds and mattresses. The methodology adopted within a multinational, multicentre, prospective, non-randomized cohort study, designed to record the occurrence and characteristics of patients vulnerable to, or with, established pressure ulcers, is described. General demographic data and the characteristics of the pressure ulcers experienced by the 2507 UK subjects recruited to the study across four UK hospitals between July 1996 and May 1998 are presented, with pressure ulcers affecting 218 subjects of whom 100 presented with ulcers on admission to hospital. Fourteen subjects developed severe ulcers, while a further 24 were admitted with full-thickness pressure ulcers. The second part of this article will report further details of the characteristics of the UK sample. Future articles will consider the subjects examined in greater detail and will also discuss the combination of this dataset with similar data collected in the USA.

Extended out-of-hospital low-molecular-weight heparin prophylaxis against deep venous thrombosis in patients after elective hip arthroplasty: a systematic review

PURPOSE

Evidence-based medicine guidelines based on venographic end points recommend in-hospital prophylaxis with low-molecular-weight heparin (LMWH) in patients having elective hip surgery. Emerging data suggest that out-of-hospital use may offer additional protection; however, uncertainty remains about the risk-benefit ratio. To provide clinicians with a practical pathway for translating clinical research into practice, we systematically reviewed trials comparing extended out-of-hospital LMWH prophylaxis versus placebo.

DATA SOURCES

Studies were identified by 1) searching PubMed, MEDLINE, and the Cochrane Library Database for reports published from January 1976 to May 2001; 2) reviewing references from retrieved articles; 3) scanning abstracts from conference proceedings; and 4) contacting pharmaceutical companies and investigators of the original reports.

STUDY SELECTION

Randomized, controlled trials comparing extended out-of-hospital prophylaxis with LMWH versus placebo in patients having elective hip arthroplasty.

DATA EXTRACTION

Two reviewers extracted data independently. Reviewers evaluated study quality by using a validated four-item instrument.

DATA SYNTHESIS

Six of seven original articles met the defined inclusion criteria. The included studies were double-blind trials that used proper randomization procedures. Compared with placebo, extended out-of-hospital prophylaxis decreased the frequency of all episodes of deep venous thrombosis (placebo rate, 150 of 666 patients [22.5%]; relative risk, 0.41 [95% CI, 0.32 to 0.54; P < 0.001]), proximal venous thrombosis (placebo rate, 76 of 678 patients [11.2%]; relative risk, 0.31 [CI, 0.20 to 0.47; P < 0.001]), and symptomatic venous thromboembolism (placebo rate, 36 of 862 patients [4.2%]; relative risk, 0.36 [CI, 0.20 to 0.67; P = 0.001]). Major bleeding was rare, occurring in only one patient in the placebo group.

CONCLUSIONS

Extended LMWH prophylaxis showed consistent effectiveness and safety in the trials (regardless of study variations in clinical practice and length of hospital stay) for venographic deep venous thrombosis and symptomatic venous thromboembolism. The aggregate findings support the need for extended out-of-hospital prophylaxis in patients undergoing hip arthroplasty surgery.

Education for women undergoing HPV testing

HPV is the main precursor to cervical cancer and is sexually transmitted. This may have psychological implications for women undergoing testing for the virus. A sensitive approach to the provision of information is required to minimise fear and stigmatisation.

Type 1 plasminogen activator inhibitor binds to fibrin via vitronectin

Type 1 plasminogen activator inhibitor (PAI-1), the primary inhibitor of tissue-type plasminogen activator (t-PA), circulates as a complex with the abundant plasma glycoprotein, vitronectin. This interaction stabilizes the inhibitor in its active conformation In this report, the effects of vitronectin on the interactions of PAI-1 with fibrin clots were studied. Confocal microscopic imaging of platelet-poor plasma clots reveals that essentially all fibrin-associated PAI-1 colocalizes with fibrin-bound vitronectin. Moreover, formation of platelet-poor plasma clots in the presence of polyclonal antibodies specific for vitronectin attenuated the inhibitory effects of PAI-1 on t-PA-mediated fibrinolysis. Addition of vitronectin during clot formation markedly potentiates PAI-1-mediated inhibition of lysis of (125)I-labeled fibrin clots by t-PA. This effect is dependent on direct binding interactions of vitronectin with fibrin. There is no significant effect of fibrin-associated vitronectin on fibrinolysis in the absence of PAI-1. The binding of PAI-1 to fibrin clots formed in the absence of vitronectin was characterized by a low affinity (K(d) approximately 3.5 micrometer) and rapid loss of PAI-1 inhibitory activity over time. In contrast, a high affinity and stabilization of PAI-1 activity characterized the cooperative binding of PAI-1 to fibrin formed in the presence of vitronectin. These findings indicate that plasma PAI-1.vitronectin complexes can be localized to the surface of fibrin clots; by this localization, they may modulate fibrinolysis and clot reorganization.

Investigating the risk of pressure damage during childbirth

The incidence of pressure ulceration is well documented within general adult hospital and community healthcare populations (Department of Health (DoH), 1992). However, within maternity units this negative outcome is largely unreported. Indeed, many trusts exclude maternity units from their regular pressure incidence and prevalence monitoring. This article will seek to raise awareness of the potential causes and areas where clinical practices could be reviewed in the light of new evidence.

Treating mixed aetiology ulcers in a man undergoing drug rehabilitation

Lower leg ulceration is a condition which is generally associated with the older population; however, medical conditions and social circumstances can place some clients at increased risk. This case study looks at the treatment of a patient undergoing drug rehabilitation whose leg ulceration developed as a direct result of his previous intravenous habit. It demonstrates that with correct assessment and management mixed aetiology ulceration can be successfully treated.

Identifying and combating the risk of pressure

Risk assessment tools for pressure sores are commonplace in most nursing settings. This article describes a situation where a woman in a maternity unit developed pressure-related injuries, and how a thorough assessment led to a solution to a surprising problem.

Management of wound sinuses

An update on the development, assessment and management of wound sinuses.

A systematic approach to complex wounds

Complex wounds fill most nurses with the feeling of unmanageable dread. This article aims to dispel such fears by showing that the nurse, once equipped with the correct physiological knowledge and an in-depth awareness of the treatments available, can provide effective wound care using the nursing process.

Molecular evidence that childhood monosomy 7 syndrome is distinct from juvenile chronic myelogenous leukemia and other childhood myeloproliferative disorders

The observation that juvenile chronic myelogenous leukemia (JCML) and childhood bone marrow monosomy 7 syndrome (Mo 7) are similar in many clinical and epidemiologic respects suggests a shared pathogenic basis and raises the possibility that the bone marrows of patients with JCML might lose chromosome 7 alleles by mechanisms that do not result in detectable cytogenetic deletions. We used a series of polymorphic markers mapped to chromosome 7 to test this hypothesis in 22 children with MPS and MDS, including 19 with JCML. All MPS and MDS samples demonstrated allelic heterozygosity with at least one chromosome 7 marker; 16 were heterozygous with probes from both 7p and 7q. Furthermore, the percentage of patient bone marrow samples heterozygous at each locus tested was similar to the frequency observed in the normal population. Whereas these data demonstrate that submicroscopic loss of large segments of chromosome 7 alleles is uncommon in children with MPS and MDS who do not have Mo 7, they do not exclude small deletions around an uncharacterized tumor-suppressor locus. Our results suggest that a number of distinct molecular events contribute to leukemogenesis, and we propose a multistep model to explain the similarities and differences between the major subtypes of childhood MPS and MDS.

Effect of tunicamycin and monensin on the transport to the cell surface and secretion of a viral membrane glycoprotein containing both N- and O-linked sugars

Most membrane glycoproteins contain either N-linked or O-linked oligosaccharides, which play important roles in correct folding, stability, and intracellular transport. Some glycoproteins, however, contain both the N- and O-linked sugars. To study the roles of the two types of glycosylation in intracellular transport we have used as a model the glycoprotein gC-1 of herpes simplex virus type 1 (HSV-1), which contains both N- and O-linked oligosaccharides. Cloned gene of gC-1 was expressed constitutively in mammalian cells to produce the gC-1 glycoprotein containing both types of glycosylation. Only a fraction of the gC-1 glycoprotein was secreted into the medium. Addition of tunicamycin blocked N-glycosylation and the gC-1 protein of reduced size containing only O-linked sugars was formed. This O-glycosylated gC-1 protein was transported to the cell surface and secreted into the medium, indicating that glycoprotein transport to and across the cell surface occurs in the absence of N-glycans. The data suggest either that O-glycans may contribute to this process or that transport can occur in the absence of both N- and O-glycans.

Tumour markers for prediction of survival and monitoring of remission in small cell lung cancer

Levels of the tumour markers neurone specific enolase (NSE), lactate dehydrogenase (LDH), chromogranin A (ChrA) and carcinoembryonic antigen (CEA) were measured in serum taken at presentation and during treatment, remission and relapse from 154 patients who received chemotherapy for small cell lung cancer at a single centre over a 6 year period. At presentation NSE was the most frequently elevated marker, being raised in 81% of patients and significantly higher in extensive as opposed to limited disease, as were LDH and ChrA. The response rate to therapy was best correlated with presentation level of ChrA, being 79% for those whose levels were within twice the upper limit of normal and 51% above (P < 0.01). Multivariate regression analysis showed NSE, performance status and albumin at presentation to be the best independent predictors of survival. Patients with NSE below twice the upper limit of normal, Karnofsky performance status of 80 or above and albumin 35 g l-1 or above had a median survival of 15 months with 25% alive at 2 years, whilst those with NSE above twice normal, Karnofsky below 80 and albumin less that 35 g l-1 had all died by 8 months. Changes in marker levels during therapy were of low predictive value for outcome although the finding of rising NSE during chemotherapy after an initial fall correlated with significantly reduced duration of remission. There was a strong inverse correlation between the NSE level at the time of response and duration of remission (P < 0.0001). Prediction of relapse was most reliable with ChrA, 52% of patients having rising levels before clinical evidence of disease recurrence.

Patterns of cell division and interkinetic nuclear migration in the chick embryo hindbrain

Early in its development, the chick embryo hindbrain manifests an axial series of bulges, termed rhombomeres. Rhombomeres are units of cell lineage restriction, and both they and their intervening boundaries form a series that reiterates various features of neuronal differentiation, cytoarchitecture, and molecular character. The segmented nature of hindbrain morphology and cellular development may be related to early patterns of cell division. These were explored by labeling with BrdU to reveal S-phase nuclei, and staining with basic fuchsin to visualise mitotic cells. Whereas within rhombomeres, S-phase nuclei were located predominantly toward the pial surface of the neuroepithelium, at rhombomere boundaries S-phase nuclei were significantly closer to the ventricular surface. The density of mitotic figures was greater toward the centres of rhombomeres than in boundary regions. Mitotic cells did not show any consistent bias in the orientation of division, either in the centres of rhombomeres, or near boundaries. Our results are consistent with the idea that rhombomeres are centres of cell proliferation, while boundaries contain populations of relatively static cells with reduced rates of cell division.

Acid pH-induced fusion of cells by herpes simplex virus glycoproteins gB an gD

Enveloped animal viruses enter host cells either by direct fusion at neutral pH or by endocytosis. Herpes simplex virus (HSV) is believed to fuse with the plasma membrane of cells at neutral pH, and the glycoproteins gB and gD have been implicated in virus entry and cell fusion. Using cloned gB or gD genes, we show that cells expressing HSV-1 glycoproteins gB or gD can undergo fusion to form polykaryons by exposure only to acidic pH. The low pH-induced cell fusion was blocked in the presence of monoclonal antibodies specific to the glycoproteins. Infection of cells expressing gB or gD glycoproteins with HSV-1 inhibited the low pH-induced cell fusion. The results suggest that although the glycoproteins gB and gD possess fusogenic activity at acidic pH, other HSV proteins may regulate it such that in the virus-infected cell, this fusion activity is blocked.

Expression from cloned DNA of biologically active glycoprotein C of herpes simplex virus type 1 in mammalian cells

A DNA fragment of the herpes simplex virus type 1 genome encoding glycoprotein C (gC-1) has been cloned into different eukaryotic expression vectors for transient and stable expression of the glycoprotein in a number of cell lines. All of these expression vectors use a non-HSV promoter, such as the adenovirus major late promoter or murine leukemia virus long terminal repeat promoter to express gC-1 in COS and CHO cells or 3T3 cells. The gC-1 protein synthesized was fully glycosylated with both N- and O-linked oligosaccharides. Synthesis of the mature 120K gC-1 glycoprotein involved partially glycosylated 100K and 105K proteins and the non-glycosylated 70K protein as intermediate molecules. Immunofluorescence studies showed that the expressed gC-1 was localized intracellularly in the nuclear envelope as well as on the cell surface. The expressed gC-1 was biologically active and could act as a receptor for the complement component C3b in the absence of other HSV proteins.

Structure and expression of the glycoprotein gene of Chandipura virus

A cDNA copy of the mRNA for the glycoprotein G of Chandipura virus, a rhabdovirus, has been cloned, sequenced, and expressed in mammalian cells. The deduced amino acid sequence of G shows that the encoded protein is a typical transmembrane glycoprotein of 524 amino acids containing a cleavable amino-terminal signal peptide, two potential N-linked glycosylation sites, a hydrophobic membrane anchor domain near the carboxy terminus, and a cytoplasmic domain at the carboxy terminus. Somewhat unusual is the appearance of two charged amino acid residues, aspartate and arginine, within the putative membrane anchor sequence. Expression of the G gene in COS cells resulted in production of a glycosylated protein of mol wt 71,000 which was recognized by anti-Chandipura antibodies. Like the viral G protein, the expressed G contained covalently linked palmitic acid. However, unlike its vesicular stomatitis virus (Indiana serotype) counterpart, the Chandipura G protein has no potential palmitate-accepting cysteine residue within its cytoplasmic domain. Thus, the covalent attachment of fatty acid to this molecule may occur at one or both of the cysteines within the membrane anchor domain. The G protein was intracellularly transported to the cell surface and could induce cell fusion at low pH, showing that the expressed G protein was biologically active.