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We examined the influence of insect cadaver desiccation on the virulence and production of entomopathogenic nematodes (EPNs), common natural enemies of many soil-dwelling insects. EPNs are often used in biological control, and we investigated the feasibility of applying EPNs within desiccated insect cadavers. Desiccation studies were conducted using the factitious host, Galleria mellonella (Lepidoptera: Pyralidae, wax moth larvae) and three EPN species (Heterorhabditis bacteriophora 'HB1', Steinernema carpocapsae 'All', and Steinernema riobrave). Weights of individual insect cadavers were tracked daily during the desiccation process, and cohorts were placed into emergence traps when average mass losses reached 50%, 60%, and 70% levels. We tracked the proportion of insect cadavers producing infective juveniles (IJs), the number and virulence of IJs produced from desiccated insect cadavers, and the influence of soil water potentials on IJ production of desiccated insect cadavers. We observed apparent differences in the desiccation rate of the insect cadavers among the three species, as well as apparent differences among the three species in both the proportion of insect cadavers producing IJs and IJ production per insect cadaver. Exposure of desiccated insect cadavers to water potentials greater than -2.75 kPa stimulated IJ emergence. Among the nematode species examined, H. bacteriophora exhibited lower proportions of desiccated insect cadavers producing IJs than the other two species. Desiccation significantly reduced the number of IJs produced from insect cadavers. At the 60% mass loss level, however, desiccated insect cadavers from each of the three species successfully produced IJs when exposed to moist sand, suggesting that insect cadaver desiccation may be a useful approach for biological control of soil insect pests., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Biological control can be considered an intentional induction of a trophic cascade, whereby the addition of herbivores' natural enemies or other habitat manipulations effectively enhance natural enemy populations, lead to reduced herbivore populations or feeding damage, and indirectly improve or protect plant health, agricultural yield, or the condition of some other biotic population or community of interest to man. The following set of papers (Denno et al., 2008; Ram et al., 2008; Stuart and Duncan, 2008; Spence et al. 2008) offer insights into the broad- and fine-scale factors that ultimately contribute to the success of biological control efforts. Many of the ideas herein were presented and discussed during a special session at the 2007 Annual Meeting of the Society of Nematologists. The goal of this session was to examine explicitly the ramifications of spatial and temporal heterogeneity in the context of effective biological control. The biological focus was primarily on interactions involving entomopathogenic nematodes (EPN), although many of the authors' conclusions are applicable to other types of nematodes, soil fauna and natural enemies in general.

Fine-scale soil nutrient enrichment typically stimulates root growth, but it may also increase root herbivory, resulting in trade-offs for plant species and potentially influencing carbon cycling patterns. We used root ingrowth cores to investigate the effects of microsite fertility and root herbivory on root biomass in an aggrading upland forest in the coastal plain of South Carolina, USA. Treatments were randomly assigned to cores from a factorial combination of fertilizer and insecticide. Soil, soil fauna, and roots were removed from the cores at the end of the experiment (8-9 mo), and roots were separated at harvest into three diameter classes. Each diameter class responded differently to fertilizer and insecticide treatments. The finest roots (< 1.0 mm diameter), which comprised well over half of all root biomass, were the only ones to respond significantly to both treatments, increasing when fertilizer and when insecticide were added (each P < 0.0001), with maximum biomass found where the treatments were combined (interaction term significant, P < 0.001). These results suggest that root-feeding insects have a strong influence on root standing crop with stronger herbivore impacts on finer roots and within more fertile microsites. Thus, increased vulnerability to root herbivory is a potentially significant cost of root foraging in nutrient-rich patches.

While plant species respond differently to nutrient patches, the forces that drive this variability have not been extensively examined. In particular, the role of herbivory in modifying plant-resource interactions has been largely overlooked. We conducted a glasshouse study in which nutrient heterogeneity and root herbivory were manipulated, and used differences in foraging among plant species to predict the influence of root herbivores on these species in competition. We also tracked the influence of neighborhood composition, heterogeneity, and herbivory on whole-pot plant biomass. When herbivores were added to mixed-species neighborhoods, Eupatorium compositifolium, the most precise forager, was the only plant species to display a reduction in shoot biomass. Neighborhood composition had the greatest influence on whole-pot biomass, followed by nutrient heterogeneity; root herbivory had the smallest influence. These results suggest that root herbivory is a potential cost of morphological foraging in roots. Root herbivores reduced standing biomass and influenced the relative growth of species in mixed communities, but their effect was not strong enough at the density examined to overwhelm the bottom-up effects of resource distribution.

Background: Direct lymphatic drainage from the skin of the anterior chest and breast to internal mammary lymph nodes does not normally occur., Methods: Preoperative lymphoscintigraphy was performed in a 55-year-old man with a 3.7 mm-thick primary melanoma on his right anterior chest, who had undergone surgery and radiotherapy to successfully treat a localized lymphosarcoma in his right axilla 35 years earlier., Results: The sentinel node in the lower right internal mammary chain, in the 5th interspace, was removed at the same time as the primary melanoma site was widely excised, and micrometastatic melanoma was subsequently identified in it. Second-tier nodes in the 4th and 3rd right interspaces were therefore removed, and adjuvant radiotherapy was given to the entire internal mammary node chain., Conclusions: This case demonstrates that major disturbance of normal lymphatic drainage pathways can result from previous surgery and/or radiotherapy. Also, the rarity of this drainage pattern indicates that attempts to identify sentinel nodes in breast cancer patients by injecting tracer into the skin overlying a tumour rather than into the breast tissue immediately adjacent to it are likely to be inaccurate in some patients, because cutaneous injection will not demonstrate the sentinel nodes in the internal mammary chain that are present in up to 40% of patients with a breast cancer.

Purpose: To analyze prognostic factors, effects of treatment, and survival for patients with cerebral metastases from melanoma., Patients and Methods: All melanoma patients with cerebral metastases treated at the Sydney Melanoma Unit between 1952 and 2000 were identified. From 1985 to 2000, patients were diagnosed and treated using consistent modern techniques and this cohort was analyzed in detail. Multivariate analysis of prognostic factors for survival was performed., Results: A total of 1137 patients with cerebral metastases were identified; 686 were treated between 1985 and 2000. For these 686 patients, the median time from primary diagnosis to cerebral metastasis was 3.1 years (range, 0 to 41 years). A total of 646 patients (94%) have died as a result of melanoma. The median survival from the time of diagnosis of cerebral metastasis was 4.1 months (range, 0 to 17.2 years). Treatment was as follows: surgery and postoperative radiotherapy, 158 patients; surgery alone, 47 patients; radiotherapy alone, 236 patients; and supportive care alone, 210 patients. Median survival according to treatment received for these four groups was 8.9, 8.7, 3.4, and 2.1 months, respectively; the differences between surgery and nonsurgery groups were statistically significant. On multivariate analysis, significant factors associated with improved survival were surgical treatment (P <.0001), no concurrent extracerebral metastases (P <.0001), younger age (P =.0007), and longer disease-free interval (P =.036). Prognostic factors analysis confirmed the important influence of patient selection on treatment received., Conclusion: This large series documents the characteristics of patients who developed cerebral metastases from melanoma. Median survival was dependent on treatment, which in turn was dependent on patient selection.

Background: Multiple randomized trials of breast conservation compared with mastectomy in early breast cancer have validated equivalence of survival. Overwhelmingly the standard management of breast conservation includes surgical removal of the tumour, axillary dissection, postoperative breast irradiation, and adjuvant systemic therapy as appropriate. The outcomes are reviewed of 832 women with early breast cancer treated by local resection and irradiation at Royal Prince Alfred Hospital over an 18 year period, with particular emphasis on the changing patterns of practice., Methods: Between September 1978 and May 1996, 832 women with early stage breast cancer were treated with conservative surgery and radiation therapy. The changes in patient, tumour and treatment factors were analysed over this time period. The outcomes of local recurrence and survival were recorded. Trends in patterns of these variables were evaluated by dividing the 18 years accrual period into three consecutive periods (1978-1983, n = 28; 1984-1990, n = 392; 1991-1996, n = 412)., Results: At a median follow up of 76 months, the 5 and 10 year actuarial local recurrence rates were 4% and 6%, respectively. Half of the local recurrences were at the primary site. Young age, extensive intraduct carcinoma, oestrogen receptor (ER) status and extranodal spread were predictive of local recurrence on multivariate analysis. The 5 and 10 year overall survival rates were 88% and 73%, respectively. Actuarial 5 year local recurrence (4%, 6%, 2%) and survival (96%, 88%, 92%) rates varied little across the three time intervals. There was an increase in median age from 46 to 56 years over the accrual period, with no change in median primary tumour size (1.5 cm). There were significant histopathological improvements in reporting margin status and ER status. Surgically, the median number of axillary lymph nodes retrieved (14) did not alter significantly. With respect to adjuvant therapies, irradiation of lymph nodes regions decreased over time. The proportion of patients receiving adjuvant hormones or chemotherapy increased significantly (18%, 35%, 54%)., Conclusions: The low local recurrence rate and high survival are consistent with published literature for early breast cancer. Changes in practice during the accrual period included improvements in histopathological reporting, a reduction in irradiation of lymph node regions, and an increase in the use of systemic therapy. These changes parallel international recommendations regarding the optimal management of early breast cancer.

We report two cases of carotid sinus syndrome secondary to head and neck malignancy. The underlying mechanisms unique to head and neck malignancy and treatments of the syndrome are discussed.

Background: Regional recurrence remains a problem in the management of patients with metastatic malignant melanoma in the cervical lymph nodes and parotid. In this study, the influence of the number of positive nodes, extracapsular spread, and the use of adjuvant radiotherapy on regional control and survival were analyzed., Methods: A non-randomized, prospectively documented series of 143 patients with histologically positive nodes in the neck or parotid was analyzed. There were 152 dissected necks or parotids: 45 of these received postoperative radiotherapy, 6 x 5.5 Gy fractions over 3 weeks; 107 were not irradiated., Results: The regional recurrence rate was 6.5% in the irradiated group, compared with 18.7% in the non-irradiated group (p = .055). The irradiated group, however, had more extensive nodal involvement than the non-irradiated group: 65% had two or more positive nodes, and 48% had extracapsular spread, compared with 40% and 19%, respectively, in the non-irradiated group. Survival was significantly worse when there was extracapsular spread (p < .05) or multiple node involvement (p < .01). By multivariate analysis, the use of adjuvant radiotherapy was associated with a trend toward improved regional control (p = .065), but survival was not improved., Conclusions: Adjuvant radiotherapy was associated with improved control of metastatic malignant melanoma in the neck and parotid; however, statistical significance was not reached. A prospective trial should be supported to clarify this question.

Background: Approximately 5% of cutaneous squamous cell carcinomas (SCC) metastasize to regional nodes. Nodal involvement may be more common for cutaneous squamous cell carcinomas of the head and neck, but few large series have reported clinical outcome after treatment of parotid gland and neck metastases from these cancers., Patients and Methods: A combined retrospective/prospective study of patients treated between 1983 and 1994 was performed. There were 69 men and 6 women, with a median age of 67 years. Twenty-nine patients had neck metastases, and 33 had parotid gland metastases, while 13 patients had involvement at both sites. Of the 75 patients, 68 were treated surgically and 50 received postoperative radiotherapy., Results: The facial nerve was sacrificed totally in 6 patients and partially in 9. Histologic extranodal spread was present in 48 (71%) of all surgically treated patients. Among 61 patients followed up to recurrence, or for greater than 12 months, 26 (43%) developed recurrence--12 in the parotid gland, 7 in the neck, and 7 in both sites. Multiple recurrences were common and occurred at a median of 8 months after surgery. Positive surgical margins were associated with poorer local disease control (P < 0.05). Cumulative survival at 5 years was 61%, but only 15 of 70 evaluable patients (21%) were eligible for follow-up at this time. Neck involvement with or without parotid gland disease was associated with an increased risk of distant metastases, but this was not statistically significant. Postoperative radiotherapy was not associated with improved disease control., Conclusion: Cutaneous, metastatic SCC involving the parotid gland and neck is an aggressive disease with a tendency to an infiltrative growth pattern and multiple recurrences. More aggressive surgery may be justified to reduce the incidence of regional failure after parotidectomy and neck dissection.

Between 1970 and 1990, 104 patients with squamous cell carcinoma (SCC) of the tonsil were treated. The median age was 58 years and 80% of patients were males. Distribution among clinical stages was: stage I, 19 patients; stage II, 12 patients; stage III, 23 patients; and stage IV, 48 patients. More than 70% of patients had initial radiotherapy as definitive treatment irrespective of stage, reflecting the treatment philosophy over much of this period. The overall survival rate was 26% at 5 years, with survival being significantly affected by T stage, clinical stage and age. Clinical node status did not significantly affect survival rates. Good local control of T1N0 cancers was achieved with radiotherapy alone, but patients with more advanced cancers did poorly. We have now moved away from a non-selective policy and use initial surgery combined with postoperative radiotherapy in most patients, reserving radiotherapy alone for mainly early tonsil cancers.

Hypoxic breathing during irradiation has been advocated as a therapeutic modality, to increase the efficacy of radiotherapy. In this form of treatment, the total and daily X-ray dose is increased by a factor of 1.25, on the assumption that all normal tissues in the beam will be protected to a similar extent by breathing gas containing a reduced oxygen concentration (usually 10%). To test this concept, we have determined the effect of varying the inspired oxygen tension on the radiosensitivity of 3 normal tissues in the mouse (kidney, jejunum and skin), and have compared these results with data from the literature for mouse lung. Reduction of the inspired oxygen tension from 21% (air) to 7-8% led to much greater radioprotection of skin (protection factor 1.37) than of lung (1.09). Protection factors for jejunum and kidney were 1.16 and 1.36 respectively. The results show that the extent of radioprotection afforded by hypoxic breathing is tissue dependent, and that great care must be taken clinically in choosing the increased radiation dose to be used in conjunction with hypoxic breathing.

Glutathione peroxidase (GSH-Px) has been implicated in mediating the radioprotective effects of glutathione (GSH). This hypothesis was tested in vivo by determining the effect of GSH-Px depletion on the radiation response of murine kidneys. Renal GSH-Px levels were depleted to 17% of control values by feeding animals a selenium deficient diet for 6 weeks; this had no significant effect on renal levels of GSH or GSH-S-transferase (GST). However, we also tested the effect of direct depletion of GSH to 3-4% of control values, using a combination of DL-buthionine sulphoximine (BSO) and diethyl maleate (DEM). Kidneys with normal or depleted levels of GSH-Px and/or GSH were irradiated with 240kVp X rays (2 fractions, 7 days apart to minimize intestinal injury). Mice breathed 7% oxygen during irradiation. Renal damage was assessed at 20, 25, and 32 weeks after the first fraction of X rays, in terms of reduced hematocrit and renal clearance of 51Cr-EDTA. Depletion of GSH-Px levels to 17% of control did not alter renal radiosensitivity, but depletion of GSH to 3-4% of control values radiosensitized the kidney by a factor of 1.4. Depletion of both GSH and GSH-Px together did not radiosensitize the kidney any more than was achieved by GSH depletion alone.