Changing presentation of prostate cancer in a UK population--10 year trends in prostate cancer risk profiles in the East of England.

BACKGROUND: Prostate cancer incidence is rising in the United Kingdom but there is little data on whether the disease profile is changing. To address this, we interrogated a regional cancer registry for temporal changes in presenting disease characteristics. METHODS: Prostate cancers diagnosed from 2000 to 2010 in the Anglian Cancer Network (n=21,044) were analysed. Risk groups (localised disease) were assigned based on NICE criteria. Age standardised incidence rates (IRs) were compared between 2000-2005 and 2006-2010 and plotted for yearly trends. RESULTS: Over the decade, overall IR increased significantly (P<0.00001), whereas metastasis rates fell (P<0.0007). For localised disease, IR across all risk groups also increased but at different rates (P<0.00001). The most striking change was a three-fold increase in intermediate-risk cancers. Increased IR was evident across all PSA and stage ranges but with no upward PSA or stage shift. In contrast, IR of histological diagnosis of low-grade cancers fell over the decade, whereas intermediate and high-grade diagnosis increased significantly (P<0.00001). CONCLUSION: This study suggests evidence of a significant upward migration in intermediate and high-grade histological diagnosis over the decade. This is most likely to be due to a change in histological reporting of diagnostic prostate biopsies. On the basis of this data, increasing proportions of newly diagnosed cancers will be considered eligible for radical treatment, which will have an impact on health resource planning and provision.

Embryonic disruption of the candidate dyslexia susceptibility gene homolog Kiaa0319-like results in neuronal migration disorders.

Developmental dyslexia, the most common childhood learning disorder, is highly heritable, and recent studies have identified KIAA0319-Like (KIAA0319L) as a candidate dyslexia susceptibility gene at the 1p36-34 (DYX8) locus. In this experiment, we investigated the anatomical effects of knocking down this gene during rat corticogenesis. Cortical progenitor cells were transfected using in utero electroporation on embryonic day (E) 15.5 with plasmids encoding either: (1) Kiaa0319l small hairpin RNA (shRNA), (2) an expression construct for human KIAA0319L, (3) Kiaa0319l shRNA+KIAA0319L expression construct (rescue), or (4) controls (scrambled Kiaa0319l shRNA or empty expression vector). Mothers were injected with 5-bromo-2-deoxyuridine (BrdU) at either E13.5, E15.5, or E17.5. Disruption of Kiaa0319l function (by knockdown, overexpression, or rescue) resulted in the formation of large nodular periventricular heterotopia in approximately 25% of the rats, which can be seen as early as postnatal day 1. Only a small subset of heterotopic neurons had been transfected, indicating non-cell autonomous effects of the transfection. Most heterotopic neurons were generated in mid- to late-gestation, and laminar markers suggest that they were destined for upper cortical laminae. Finally, we found that transfected neurons in the cerebral cortex were located in their expected laminae. These results indicate that KIAA0319L is the fourth of four candidate dyslexia susceptibility genes that is involved in neuronal migration, which supports the association of abnormal neuronal migration with developmental dyslexia.

Basal cell carcinoma epidemiology in the UK: the elephant in the room.

BACKGROUND: UK Cancer registries have difficulties in recording the incidence of basal cell carcinoma (BCC). AIM: To estimate the total numbers of BCCs in the UK requiring surgical treatment. METHODS: The histopathology records of each year from 1999 to 2010 were examined to estimate the total annual numbers of BCCs and of people with BCC in the East Norfolk and Waveney area of the UK. RESULTS: Over this period, the numbers of patients with surgically treated BCCs increased by 81%, and the numbers of BCCs by 70%. The ratio of BCCs recorded by the cancer registry was 2-2.2 times lower than that recorded in the histopathology data. Extrapolating the data to the UK population suggests that in 2010, approximately 200,000 patients had 247,000 BCCs treated surgically (this estimate does not include those treated by other means such as cryotherapy, topical chemotherapy, photodynamic therapy or radiotherapy, without histology). In 2008, 114,000 nonmelanoma skin cancers were registered in England and Wales and 309,000 total cancers (excluding nonmelanoma skin cancers) were registered in the UK. CONCLUSIONS: These data indicate that in the UK, BCC is nearly as common as all other cancers in all other body sites combined.

The incidence of basal cell carcinoma in the under-30s in the UK.

BACKGROUND: Basal cell carcinoma (BCC) is the commonest cancer in many countries, but the current incidence in young people from the UK is unknown. AIM: To ascertain a recent incidence of BCC in the under-30 population in the UK. Methods. Cancer registry data from part of the Eastern Region of the UK was analysed for two periods: 1981-1989 and 1998-2006. Case notes were examined for a cohort of the patients from 1998 to 2006. RESULTS: The incidence of BCC increased from 0.73 to 1.79 per 100 000 in those aged < 30 years over the study period. More than half (55%) of BCCs were on the head and neck, and the most common histological subtype was superficial BCC (38%). CONCLUSIONS: The reported incidence of BCC in those aged < 30 years has increased by 145% during this period, corresponding to an average annual increase of 8.53%. This may be partially due to earlier presentation and to increased use of surgical treatments.

The association of diagnosis in the private or NHS sector on prostate cancer stage and treatment.

BACKGROUND: To examine associations of private healthcare with stage and management of prostate cancer. METHODS: Regional population-based cancer registry information on 15 916 prostate cancer patients. RESULTS: Compared with patients diagnosed in the National Health Service (NHS) (94%), those diagnosed in private hospitals (5%) were significantly more affluent (69 versus 52% in deprivation quintiles 1-2), younger (mean 69 versus 73 years) and diagnosed at earlier stage (72 versus 79% in Stages

How safe is it to transplant organs from deceased donors with primary intracranial malignancy? An analysis of UK Registry data.

Patients dying from primary intracranial malignancy are a potential source of organs for transplantation. However, a perceived risk of tumor transfer to the organ recipient has limited their use. We evaluated the risk of tumor transmission by reviewing the incidence in patients transplanted in the UK. Information from the UK Transplant Registry was combined with that from the national cancer registries of England, Wales and Northern Ireland to identify all organ donors between 1985 and 2001 inclusive with a primary intracranial malignancy and to identify the occurrence of posttransplant malignancy in the recipients of the organs transplanted. Of 11,799 organ donors in the study period, 179 were identified as having had a primary intracranial malignancy, including 33 with high-grade malignancy (24 grade IV gliomas and 9 medulloblastomas). A total of 448 recipients of 495 organs from 177 of these donors were identified. No transmission of donor intracranial malignancy occurred. Organs from patients dying from primary intracranial malignancy, including those with high-grade tumors, should be considered for transplantation and the small risk of tumor transmission should be balanced against the likely mortality for potential recipients who remain on the transplant waiting list.

Self-reported driving behaviour and attitudes towards driving under the influence of cannabis among three different user groups in England.

The study characterized self-reported driving behaviour, attitudes towards driving and assumptions about the effects of cannabis on driving, among two different volunteer groups: 63 regular cannabis users (RCUs; cannabis use>monthly) and 46 undergraduate student users, all from the West Midlands. More detailed information was provided by structured interviews with an additional sample of 23 regular users from southern England. Within each group, many respondents had driven whilst under the influence of cannabis (regular users, 82%; students, 40%; interviewees, 100%). Majorities among the regular users and interviewees continued to do so at least monthly. Most users believed that cannabis impaired driving only slightly. More stops by the police for drug-driving than for drink-driving were reported, but these rarely resulted in conviction and were not deterrent. Hence, cannabis users are very willing to drive after using the drug (often combined with alcohol), and even while intoxicated. They consider its effects on driving to be minimal; indeed, many consider it to promote better driving. Attitudes towards drink-driving were much more negative. Finally, most interviewees said that roadside drug testing would be the only efficacious deterrent to drug-driving.

Effect of high energy electron irradiation on the electromechanical properties of poly (vinylidene fluoride-trifluorethylene) 50/50 and 65/35 copolymers.

High energy electron irradiation with a broad range dosage was carried out on poly(vinylidene fluoride trifluorethylene) copolymer 65/35 mol% and 50/50 mol% films at different temperatures from room temperature to a temperature close to the melt temperature. The effect of irradiation on the properties of the films, such as electric field-induced strain, dielectric and polarisation behaviors, and mechanical modulus, is presented. The irradiated films can exhibit a very large electric field-induced strain, more than 4.5% longitudinal strain, and 3% transverse strain. The transverse strain of the stretched film can compare with the longitudinal strain; that of the unstretched film is much smaller than the longitudinal strain. With regard to the dielectric and polarization behaviors, we found that irradiation changes the copolymer from a typical ferroelectric to a relaxor ferroelectric in which the behavior of microregions under the electric field plays the key role. Between the two copolymers studied, we found that the 65/35 copolymer is preferred for both longitudinal and transverse strain generation. A model is proposed to explain the experimental results that the amplitude of the charge electrostrictive coefficient (Q) increases with decreasing crystallinity.

Chemical synthesis and biological properties of novel fluorescent antifolates in Pgp- and MRP-overexpressing tumour cell lines.

We have synthesised a series of fluorescent analogues of methylbenzoprim, a diaminopyrimidine antifolate which we have previously shown to exhibit in vivo antitumour activity in a methotrexate (MTX) "transport-resistant" tumour cell line. The analogues bear the dansyl, nitrobenzoxodiazole or methoxycoumarin fluorophores. The cytotoxicity of the compounds was evaluated using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay against two human lung cancer cell lines, together with their multidrug resistant (MDR) sublines. H69/P is a small cell line and its multidrug resistant subline H69/LX4 overexpresses P-glycoprotein (Pgp). COR-L23/P is a large cell line and its multidrug resistant subline COR-L23/R overexpresses the multidrug resistance associated protein (MRP). IC50 values for the compounds (i.e. concentration to reduce cell growth by 50%) in the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay ranged from 0.20 to 0.81 microM in the H69 parental line and from 0.83 to 5.10 microM in the COR-L23 parent line. The MDR sublines both showed clear cross-resistance to each of the compounds, with resistance factors (ratio of IC50 value in resistant vs parental cell line) ranging from 16 to 137 in H69/LX4 and from 5 to 16 in COR-L23/R. For compounds (10) and (11) where drug accumulation was studied using flow cytometry, resistance was associated with an approximately 10-fold reduction in cellular drug accumulation over a period of 30 min. The drug resistance modifiers verapamil (used at 6.6 microM) and cyclosporin A (used at 4.2 microM) were tested for their ability to sensitise the resistant lines. Whereas verapamil showed little activity, cyclosporin A partially restored the activity of compound (10), and fully restored the activity of compound (11) in H69/LX4 cells. This sensitisation of H69/LX4 by cyclosporin A was associated with a partial restoration of the drug accumulation deficit in this line. Hence, these novel lipophilic antifolates appear to be substrates for both the P-glycoprotein and MRP resistance mechanisms. Therefore, although they have been designed to overcome one mechanism of methotrexate resistance, namely impaired drug transport, this has been achieved only at the cost of rendering them susceptible to alternative mechanisms.

Alternative delivery of keratinocytes using a polyurethane membrane and the implications for its use in the treatment of full-thickness burn injury.

The Epicel ASAProgram service generates autologous keratinocyte grafts used for the closure of full-thickness wounds in moderately and severely burned patients. The manufacturing process used to generate Epicel service autografts (ESA) is based upon the keratinocyte co-culture technique described by Rheinwald and Green which employs murine Swiss 3T3/J2 fibroblasts as feeder cells. Recently, a technique has been described that employs a polyurethane wound dressing, HydroDerm (HD, Innovative Technologies, Ltd), as a delivery vehicle for cultured keratinocytes intended for autologous grafting. We have examined the practical feasibility of this technique and report on testing the ability of HD to support keratinocyte growth and epithelium formation in vitro, at the air-liquid interface (ALI), and in vivo, after grafting to full-thickness wounds created on the backs of athymic (Swiss Nu/Nu) mice. The results demonstrate that keratinocytes grow on the HD dressing in Gibco SFM at a rate that is approximately 15 per cent of that observed when cells are cultivated on tissue culture (TC) plastic using standard techniques, yet the cells retain their proliferative capacity and form an epithelium in vitro when cultivated at the ALI on a dermal substrate. Keratinocyte-seeded HD membranes were also transferred to full-thickness wounds in athymic mice. Animals grafted with cells seeded to HD developed human epithelium, as revealed by species-specific detection of involucrin and evolved a normal attachment to the wound substratum, as demonstrated through the expression of dermally opposed laminin and alpha 6 beta 4 integrin. The ability of keratinocytes to maintain proliferative potential after seeding onto HD and their ability to form a properly oriented epithelium in vitro and in vivo suggests that this wound dressing may be useful as a vehicle for autologous keratinocyte grafting and help to provide earlier epithelial coverage to the burned patient. However, because of the slow proliferation rate of keratinocytes on HydroDerm, timely graft delivery would be best achieved by combining cell expansion via the Rheinwald and Green culture system, followed by the seeding of cells onto HydroDerm in a reduced calcium medium for subsequent autologous grafting.

Changes in anion permeability following hypotonic challenge in rat brain endothelial cells: different responses in primary cultures and in immortalised RBE4 cells.

Hypotonicity-induced anion permeability changes were investigated but not detected in immortalised (RBE4) rat brain endothelial cells using iodide efflux measurements. Large, rapid increases were however observed in primary cultured cells. Both cell types were reinvestigated following culture in a common growth factor-depleted medium. Responses were still undetectable in the immortalised RBE4 cells. Reduced responses were observed in the primary cultured cells that also showed altered morphology and decreased activity of another transporter, P-glycoprotein. Thus both immortalisation and different culture conditions may alter functional expression in these cells of transporters involved in hypotonicity-induced anion permeability changes.

Modulation by acrolein and chloroacetaldehyde of multidrug resistance mediated by the multidrug resistance-associated protein (MRP).

Acrolein (AC) and chloroacetaldehyde (CHA) are metabolites of the non-multidrug resistance cytotoxic drugs cyclophosphamide and ifosfamide. It has previously been reported that both metabolites can induce extensive depletion of glutathione (GSH) in vitro and in vivo and that this depletion occurs at drug concentrations in the micromolar range. A link between the function of the multidrug resistance-associated protein (MRP) and the intracellular concentration of GSH has also been demonstrated. To determine whether AC and CHA can modulate the function of MRP by inducing GSH depletion, we used two human lung cancer cell lines overexpressing MRP: the large cell carcinoma cell line COR-L23/R and the adenocarcinoma cell line MOR/R0.4, along with their respective sensitive parental lines, COR-L23/P and MOR/P. We showed that micromolar concentrations of AC and millimolar concentrations of CHA are able to deplete GSH concentrations in the cell lines studied. In addition, concentrations of 50 micrometer AC and 5 mm CHA could completely reverse the daunorubicin (DNR) and vinblastine accumulation deficit present in COR-L23/R and partially reverse the DNR accumulation deficit in MOR/R0.4. In contrast, AC and CHA did not reverse the drug accumulation deficit in the P-glycoprotein-overexpressing lung cancer cell line H69/LX4. The effect of CHA and AC on drug accumulation was related to the GSH depletion, as we found a concentration-dependent relationship between the GSH levels and the reversal of the accumulation deficit for both AC and CHA. To substantiate further this correlation, we increased cellular GSH content in AC- and CHA-treated cells with the GSH ethyl ester. An increase in cellular GSH levels in CHA- and AC-treated COR-L23/R cells was accompanied by a restoration of the DNR accumulation deficit. No significant effect of the GSH ethyl ester was detected on DNR accumulation in COR-L23/P parental cells. In conclusion, treatment with AC or CHA can reverse the drug accumulation deficit of MRP-overexpressing cells, and this effect appears to be mediated by GSH depletion.

On the relationship between the probenecid-sensitive transport of daunorubicin or calcein and the glutathione status of cells overexpressing the multidrug resistance-associated protein (MRP).

Cells exposed to calcein acetoxymethyl ester (calcein AM) in the growth medium become fluorescent following cleavage of calcein AM by cellular esterases to produce the fluorescent derivative calcein. It has previously been shown by others that multidrug resistant cells which overexpress P-glycoprotein accumulate much less fluorescent calcein than the corresponding parental cells. We have now examined the transport of calcein in multidrug resistant cells which overexpress an alternative transporter, the multidrug resistance-associated protein (MRP). Accumulation of calcein fluorescence was greatly reduced in the MRP-overexpressing human lung cancer cell lines COR-L23/R and MOR/R compared with their parental lines. Energy depletion resulted in a considerably increased accumulation in the resistant lines. Treatment of resistant cells with buthionine sulfoximine (BSO), which depletes cellular glutathione (GSH), did not affect calcein accumulation, in marked contrast to our previous results for daunorubicin or the fluorescent probe rhodamine 123. Genistein, verapamil, cyclosporin A and ouabain were also each able to modify, to some extent, accumulation of daunorubicin, whilst having essentially no effect on calcein accumulation. However, the organic anion transport inhibitor probenecid was able to increase accumulation of both calcein and daunorubicin in the resistant cells. Genistein and verapamil treatment preferentially reduced the GSH content of resistant cells, whilst probenecid did not. However, probenecid caused a clear decrease in release of GSH from resistant cells into the medium.

Localisation of the multidrug resistance-associated protein, MRP, in resistant large-cell lung tumour cells.

The drug transport protein, P-glycoprotein, confers multidrug resistance (MDR) by expelling drugs across the cell surface. The structurally similar multidrug resistance-associated protein, or MRP, is also involved with drug efflux. In MDR variants of the human lung tumour cell line COR-L23 that overexpress MRP, there are also changes in intracellular drug distribution. To ascertain whether MRP could be involved in either process, experiments were performed to identify where MRP was located in these cells. Following separation of membranes by sucrose gradient centrifugation, MRP was found predominantly in the lighter membrane fractions containing plasma membrane enzyme activity. Immunofluorescent staining with a monoclonal antibody raised against MRP confirmed that MRP is present at the cell surface of these MDR lung tumour cells.

Expression of vascular endothelial growth factor and its receptors flt and KDR in ovarian carcinoma.

BACKGROUND: Two thirds of patients with ovarian carcinoma have advanced disease at diagnosis and have poor prognoses because of the presence of highly invasive carcinoma cells and rapidly accumulating ascitic fluid. Vascular endothelial growth factor (VEGF), a potent mitogen of endothelial cells, is produced in elevated amounts by many tumors, including ovarian carcinomas. The known human receptors for VEGF, flt and KDR, are both cell surface tyrosine kinases and are expressed predominantly on endothelial cells. Acting through these receptors, VEGF may stimulate angiogenesis and promote tumor progression. PURPOSE: We aimed to clarify the function of VEGF in tumor development by identifying the cells in ovarian carcinoma tissue that express VEGF and its receptors. METHODS: VEGF, flt, and KDR expression was localized by in situ hybridization and immunohistochemistry in frozen sections of primary tumors from five patients with ovarian carcinoma and from metastases of ovarian carcinoma from three different patients. Reverse transcription followed by polymerase chain reaction (RT-PCR) and an enzyme-linked immunosorbent assay were used to analyze VEGF, flt, and KDR expression in six epithelial cell lines derived from ovarian carcinoma ascites from five additional patients. RESULTS: Messenger RNAs (mRNAs) encoding VEGF, flt, and KDR were detected in primary ascitic cells and in three of four ovarian carcinoma cell lines examined by RT-PCR. Two novel complementary DNAs that may encode truncated, soluble forms of flt were cloned from one primary source. VEGF levels of 20-120 pM were found in culture media conditioned by the cell lines. Elevated expression of VEGF mRNA was found in all primary tumors and metastases, especially at the margins of tumor acini. VEGF immunoreactivity was concentrated in clusters of tumor cells and patches of stromal matrix. flt immunoreactivity was confined to tumor blood vessels, but flt mRNA was not detected by in situ hybridization. In contrast, KDR mRNA was detected not only in vascular endothelial cells but also in tumor cells at primary malignant sites. CONCLUSIONS: VEGF is expressed by tumor cells in primary and metastatic ovarian carcinoma and accumulates in the stromal matrix. Its receptors, flt and KDR, are expressed by some tumor cells that coexpress VEGF. This is the first localization of KDR expression in nonendothelial cells. IMPLICATIONS: Coexpression of VEGF and KDR by tumor cells in ovarian carcinoma raises the possibility of autocrine stimulation and of therapeutic strategies targeting this receptor-ligand interaction.

A 190-kilodalton protein overexpressed in non-P-glycoprotein-containing multidrug-resistant cells and its relationship to the MRP gene.

BACKGROUND: A 190k (190-kilodalton) membrane protein has been identified in several multidrug-resistant (MDR) cell lines that show decreased drug accumulation without expression of P-glycoprotein. It is not clear whether this 190k protein is involved directly in drug efflux. Recently, a gene for a putative transporter protein, MRP (multidrug resistance-associated protein) has been sequenced and localized to chromosome 16. The protein encoded by this gene contains a 7-amino-acid sequence present in the synthetic peptide used to generate the antiserum recognizing the 190k protein. PURPOSE: The study was undertaken to clarify the relationship of the 190k protein to MRP gene expression in non-P-glycoprotein-containing MDR cells of the large-cell and adenocarcinoma lung cancer lines, COR-L23 and MOR. METHODS: Expression of the 190k protein was determined by Western blot analysis and that of the MRP gene by polymerase chain reaction amplification of complementary DNA reverse transcribed from RNA. Abnormalities of chromosome 16 were investigated in chromosome spreads by fluorescence in situ hybridization. RESULTS: The amount of detectable 190k protein is closely associated with degree of drug resistance. Cell lines surviving in higher drug concentrations have greater amounts of protein, and revertant lines grown without drug for up to 28 weeks show reduced expression of the protein together with enhanced drug sensitivity. The 190k protein appears to be one of the major proteins differentially expressed in membranes of drug-resistant cells. The amount of MRP messenger RNA correlates closely with that of the 190k protein. The MDR cells contain amplified chromosome 16 material with many double minutes in the large-cell lung tumor lines and an enlarged chromosome 16 in the adenocarcinoma lines. CONCLUSION: The 190k protein detected immunologically is likely to be the protein, encoded by the MRP gene, which becomes overexpressed in these cells as a consequence of chromosomal amplification and fragmentation. IMPLICATION: Though associated with drug resistance, enhanced drug efflux, and decreased drug accumulation in cell lines, the role of this protein in clinical resistance has yet to be determined.

Amphotericin B lipid complex in the treatment of experimental cryptococcal meningitis and disseminated candidosis.

In the quest for safer and more effective antifungal agents, amphotericin B (AMB) has been placed in a variety of lipid preparations. In this study, we examined the efficacy of amphotericin B lipid complex (ABLC) on experimental cryptococcal meningitis and disseminated candidosis. This formulation is relatively safe compared to the parent compound, and therefore doses ten times greater than the commercial amphotericin B deoxycholate can be given to rabbits. Although at equal doses the ABLC preparation is less potent than AMB, a higher dose of ABLC was rapidly fungicidal in the contexts of both a central nervous system infection with Cryptococcus neoformans during immune suppression, and a heart and kidney infection with Candida albicans. Rapid sterilization of tissue should be a goal of antifungal drug therapy, particularly in the immune compromised host. From these studies, this AMB lipid formulation has the ability to produce rapid fungicidal activity in vivo, but it requires higher doses than AMB deoxycholate. Clinical trials in humans must examine carefully the therapeutic-toxic ratio in dose-escalation protocols to determine the optimal dosage strategy for this agent.

A freeze-fracture study of the cuticle of adult Nippostrongylus brasiliensis (Nematoda).

The surface of the cuticle of adult Nippostrongylus brasiliensis has been studied by means of the freeze-fracture technique and by transmission electron microscopy. Some of the surface coat appears to have been shed from the surface of the cuticle of adults fixed in situ in the intestine of its host and from the surface of individuals removed from the intestine and freeze-fractured. Freeze-fracturing the cuticle of individuals removed from the host has shown that this surface coat varies in thickness from 30 to 90 nm. The epicuticle is about 20 nm thick and cleaves readily to expose E- and P-faces. The P-face of the epicuticle possesses a small number of particles, similar to intra-membranous particles, whilst the E-face possesses a few, widely scattered depressions. Despite the presence of these particles the epicuticle is not considered to be a true membrane. Freeze-fracturing the remainder of the cuticle has confirmed its structure as described by conventional transmission electron microscopy. Clusters of particles on the P-face of the outer epidermal (hypodermal) membrane and corresponding depressions on the E-face of the membrane are though to be associated with points of attachment of the cuticle to the epidermis (hypodermis). No differences in appearance of the cuticle and its surface layers were observed in individuals taken from 7-, 10-, 13- and 15-day infections.

Management of agricultural injuries and illness.

Until recently, rural health care nursing issues had not been widely addressed. Appropriate concerns for an ill or injured worker in an urban setting are compounded in the rural setting with its isolation and lack of resources. Farming is very diversified, and different parts of the country face different types of problems. Nurses in the rural community have a responsibility to learn as much as possible about the agricultural hazards common to their area. Health care professionals must be able to make rapid, accurate assessments of the injured or ill farmer, taking into account the nature of the machine and environmental factors that may cause additional problems. Proper care of the injured or ill farmer must be initiated at the rural hospital for optimal recovery to take place.

Derivation and characterisation of a mouse tumour cell line with acquired resistance to cyclosporin A.

Cyclosporin A (CsA) is an effective modifier of multidrug resistance. We have studied (a) the possibility that cells grown in increasing concentrations of CsA acquire cellular resistance to the agent and, (b) whether such cells have a multidrug resistant phenotype. Sublines of the EMT6 mouse tumour cell line were developed which were able to grow in 75 and 200 micrograms/ml of CsA, respectively. The resistant sublines grew slowly in the presence of CsA but reverted to control growth rates, whilst maintaining resistance, when the drug was removed. P-glycoprotein (Pgp) was not detectable in the resistant sublines by immunocytochemistry. The CsA-resistant cells were not cross-resistant to doxorubicin or vincristine but showed a clear degree of cross-resistance to the calcium transport blocker, verapamil. Cellular accumulation of both [3H]CsA and [3H]daunorubicin was significantly increased in the EMT6/CsA200R subline compared with the parent line. In the EMT6 parent line, which expresses very low levels of Pgp, 10-30-fold sensitisation to doxorubicin may be achieved using 0.1-5 microgram/ml of CsA. Similar sensitisation by CsA was also seen in the CsA-resistant sublines.