Phytotoxicants from microorganisms and related compounds

Phytotoxic compounds produced by microorganisms are reviewed. Their utilisation as leads to new herbicides is explored in three chemical classes : 2-aminoalk-3-enoic acids, ether derivatives of 3-hydroxycyclobut-3-ene-1,2-diones, and 2-(acylaminooxy)acetic acid derivatives. It is concluded that some bacteria and fungi yield compounds possessing sufficient herbicidal activity to be valuable as herbicides as such, or as leads for chemical optimisation.     

Clonality and clinical behavior of canine indolent lymphoma

Introduction: Canine lymphomas with a follicular architecture are biologically indolent and include follicular (FL), mantle cell (MCL), marginal zone (MZL) and T‐zone (TZL) types. They are under recognized and have long survival regardless of treatment. Methods: 70 cases of canine lymphoma with fading follicular hyperplasia (FFH) received¹ over 1996 to present were reviewed. Diagnoses were determined by consensus of three pathologists^1,2 on phenotyped tissues. Clonality for B and T‐cell receptor genes was determined on DNA from paraffin blocks via PCR on 53 of 70 cases². Results: Of the total of 70 cases 52 were of B‐cell type (MZL 44, FL 4, MCL 3, MALT 1) and 9 were of T‐cell type (TZL). 9 cases of benign hyperplasia were included to assist in defining the histologic boundaries of neoplasia. Case presentation included splenic 16, and nodal 54. For 44 cases called MZL on histologic criteria, DNA was available on 33 of which 26 (78.8%) were clonal for B‐cell rearranged gene including 5 also clonal for T‐cell receptor, one clonal for T‐cell only and 6 cases negative for both and considered benign. For TZL, DNA was available on 6 of 9 cases of which 3 were clonal for T‐cell receptor, 1 for B‐cell, 1 for both and 2 polyclonal for both. Conclusions: An Ohio review of 380 cases of canine nodal lymphoma found 29% of cases to be of indolent type as described here and thus a very significant part of the patient population. Seven of 10 cases of MZL treated at Illinois with follow‐up died of other causes than lymphoma at an average of 18.8 months after diagnosis. One of the other three was lost to follow‐up, one was euthanized at owners’ choice at 9.5 m. after diagnosis still in good health and the other was terminated 3 m after diagnosis with concurrent lung carcinoma.     

Retropective Evaluation of Survival Time of Dogs with Stage III Osteosarcoma that Undergo Treatment

Introduction:  Stage III osteosarcoma generally carries a grave prognosis. Despite this, some owners elect to treat using palliative or curative intent protocols. The purpose of this study was to determine the survival times for dogs with stage III osteosarcoma that undergo treatment and to evaluate the variables that affect survival time.
Methods:  Retrospective study using the CSU Animal Cancer Center osteosarcoma data base. Search criteria included dogs diagnosed with osteosarcoma 1985–2004 with metastasis at the time of presentation. Dogs were excluded if they were euthanized at the time of diagnosis (13 dogs) or lost to follow‐up (10 dogs). There were 90 cases for analysis. The survival times were compared based on the primary tumor site, site of metastasis, treatment given, age, sex and breed.
Results:  Survival times in days ranged from 0 to 1583 days. The overall median survival time was 76 days. The one‐year, two‐year and three‐year percent survival were 7%, 4.7% and 3.5%, respectively. Treatment included various combinations of chemotherapy, surgery, radiation therapy, bisphosphonates and NSAIDs. Findings included an increased survival time with surgery and adjuvant therapy compared with surgery alone and a decreased survival time with metastasis to the lung or lymph node.
Conclusions:  Treatment of dogs with stage III osteosarcoma can result in variable survival times. Multimodality therapy appears to result in longer survival times. Metastasis to the lung or lymph node correlated with a decreased survival time.     

Leptospirosis and tularaemia in raccoons (Procyon lotor) of Larimer County, [corrected] Colorado

Raccoons (Procyon lotor) are commonly implicated as carriers of many zoonotic pathogens. The purpose of this cross-sectional study was to look for Leptospira interrogans and Francisella tularensis in opportunistically sampled, free-ranging raccoons of Larimer Country, Colorado, USA. Sixty-five animals were included in the study and testing consisted of gross post-mortem examination, histopathology, and both immunohistochemistry and PCR for L. interrogans and F. tularensis. No significant gross lesions were identified and the most common histological lesions were lymphoplasmacytic interstitial nephritis and pulmonary silicosis; rare periportal hepatitis, splenic lymphoid hyperplasia and small pulmonary granulomas were also identified. Of 65 animals, 20 (30%) were positive for Leptospira on IHC but only one by PCR. Animals with inflammation in their kidneys were seven times more likely to be positive for Leptospira than animals without inflammation. The severity of inflammation was variable but often mild with minimal associated renal pathology. One animal was positive for Francisella on both IHC and PCR; IHC staining was localized to histiocytic cells within a pulmonary granuloma. In Colorado the significance and epidemiology of Leptospira is poorly understood. The high prevalence of infection in raccoons in this study population suggests that this species may be important in the regional epidemiology or could be used to estimate risk to domestic animals and humans. Identification of a single Francisella positive animal is significant as this is an uncommon disease in terrestrial animals within the state; the apparently higher prevalence in this peridomestic species implies that raccoons may be good indicators of the pathogen in the region. The results of this study suggest that raccoons may serve as effective sentinels for both Leptospira and Francisella in the state of Colorado. Further studies are needed to better characterize the prevalence and epidemiology of both organisms within the region.     

Analysis of outcome in dogs that undergo secondary amputation as an end‐point for managing complications related to limb salvage surgery for treatment of appendicular osteosarcoma

Appendicular osteosarcoma (OSA) remains a prevalent musculoskeletal cancer in dogs and definitive local control followed by adjuvant cytotoxic chemotherapy is considered the gold standard approach. Several studies support surgical limb salvage as a means of local control with similar outcomes compared with limb amputation. Complications are well described for limb salvage but little is known of dogs that undergo secondary amputation as a result of complications and outcomes specific to this group. A retrospective analysis of dogs in an institutional primary bone tumour registry was performed to identify dogs diagnosed with histologically confirmed OSA treated with surgical limb salvage with a technique that required an implant to reconstruct the osseous defect. A total of 192 dogs were identified with 31 dogs undergoing secondary amputation representing a limb preservation rate of 84%. A total of 111 dogs were analysed: 31 secondary amputation cases and 80 controls were selected for comparison. The most common reasons for secondary amputation were local recurrence (LR) and surgical site infection (SSI), with odds ratios of 3.6 and 1.7, respectively. Dogs that underwent secondary amputation had a significantly (P = .05) longer median disease specific survival time (ST) (604 days) compared with the control group (385 days). Dogs lived for a median of 205 days beyond secondary amputation and 97% had good functional outcome. Significant independent factors that positively influenced ST were secondary amputation, moderate SSI, severe SSI and age.