Tolerability and outcome of palliative treatment for metastatic pulmonary carcinoma in cats.

OBJECTIVES: Pulmonary carcinoma is uncommon in cats and reporting of outcomes following medical treatment is limited, especially in presence of metastases. The aim of this study was to describe the outcome of cats affected by metastatic primary pulmonary carcinoma and to evaluate the tolerability of palliative treatment in this patient population. MATERIALS AND METHODS: Medical records were searched for cats with a cytological or histopathological diagnosis of primary pulmonary carcinoma and evidence of metastatic disease. Cats were treated with antineoplastic agents, corticosteroids, non-steroidal anti-inflammatory drugs (NSAIDs) or received no systemic treatment. Cases in which thoracic CT was not performed, and those lacking definitive diagnosis by cytology or histopathology or receiving curative-intent surgery were excluded. RESULTS: Thirty-four cats were identified: 18 were treated with antineoplastic agents and 16 received corticosteroids, NSAIDs or no treatment. Presenting clinical signs included coughing (53%), tachypnoea (26%), gastrointestinal signs (35%) and lethargy (18%). CT scan identified metastases to the lung parenchyma in all cases and additional metastatic lesions in 10 of 34 (59%) cases; pleural effusion was detected in 11 cases (32%). The overall median survival time for all cats was 64 days [range 1-1352 days; 95% confidence interval (CI) 48-164]. Presence of respiratory signs at presentation was the only factor influencing survival in the multivariable analysis. CLINICAL SIGNIFICANCE: Medical treatment was well tolerated and appeared to palliate clinical signs in cats with metastatic pulmonary carcinoma, albeit with a modest duration and short overall survival. The role and benefit of chemotherapy/antineoplastic agents versus conventional palliative drugs in this setting remains unclear.

Outcome of dogs with intermediate grade low mitotic index high Ki67 mast cell tumours treated with surgery and single agent lomustine.

OBJECTIVES: The objective of this retrospective study was to evaluate the outcome of dogs when grade II mast cell tumour (MCT) with low mitotic index (MI) and high Ki67 were treated with adjuvant lomustine. ANIMALS: Client owned dogs with spontaneously occurring disease treated with adjuvant chemotherapy for grade II mast cell tumour with low MI (≤5/10HPF) and high Ki67 (>1.8%) with no evidence of metastatic disease at presentation. PROCEDURES: Lomustine was administered every 3 weeks with three or four planned cycles. Response to treatment was assessed by regular re-staging ultrasound with or without cytopathological examination of liver and spleen or through medical records from the referring veterinarian. Disease-free interval (DFI) and median survival time (MST) were calculated using Kaplan-Meier method. RESULTS: Twenty-one dogs were included. All dogs underwent surgical excision and two dogs received adjuvant radiotherapy. None of the patients developed local recurrence. Three dogs (14.3%) developed metastatic disease. The DFI of these dogs was 141, 186 and 223 days. Median follow-up period of the whole study population was 1112 days (358-2619). MST for patients with metastatic disease was 417 days. MST of the whole group was not reached. One-year and 2-year survivals were 95.2% and 90.5%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: This study population had low rates of tumour recurrence and improved survival compared to previously published data of similar population of dogs with low MI/high Ki67 MCT without adjuvant chemotherapy.

Haematologic toxicity in dogs with mast cell tumours treated with vinblastine/prednisolone chemotherapy with/without radiotherapy.

OBJECTIVES: To determine whether dogs with surgically excised mast cell tumours receiving a vinblastine/prednisolone chemotherapy protocol in combination with radiation therapy are at greater risk of myelosuppression than patients receiving the chemotherapy protocol alone. MATERIALS AND METHODS: Retrospective study of clinical records of dogs with mast cell tumours that, subsequent to surgical excision, had received combination vinblasine/prednisolone chemotherapy. Dogs were assigned to two groups: those treated with adjunctive radiotherapy and vinblastine/prednisolone (RT group) and those treated with surgery followed by vinblastine/prednisolone alone (control group). Haematology results were compared between groups. RESULTS: Forty-three cases and 43 controls of similar breed, age and bodyweight were included. Concurrent radiation and vinblastine chemotherapy did not appear to increase the risk of neutropenia, which was observed in 18.6 and 23.2% of cases in the RT and control groups, respectively. CLINICAL SIGNIFICANCE: Radiation and vinblastine chemotherapy can be safely combined in dogs with mast cell tumours without increasing the risk of clinically important myelosuppression.

Outcome and prognostic factors in medically treated canine prostatic carcinomas: A multi-institutional study.

Literature describing medical treatment of canine prostatic carcinoma (PC) is sparse. The aims of this study were to assess outcomes, including time to progression (TTP) and median survival time (MST), of canine PC treated with non-steroidal anti-inflammatory drugs (NSAIDs) and/or chemotherapy, and to identify prognostic factors. Records from 8 institutions were searched for dogs with cytologically or histologically confirmed PC without bladder involvement: 67 dogs were included. Presenting signs were urinary (25), gastrointestinal ([GI], 11) and systemic (3); 16 dogs had GI and urinary signs, 7 dogs had systemic signs with concurrent GI or urinary signs and in 5 dogs the tumour was an incidental finding. Out of 27 dogs, 9 (33%) had positive urine culture. Metastases were identified in 26 dogs to lymph nodes (19), lungs (10), bone (2) and liver (1). Treatment included NSAIDs and chemotherapy (32), NSAIDs alone (31) and chemotherapy alone (4). The overall MST was 82 days (range 9-752) and median TTP was 63 days (range 9-752). Dogs receiving NSAIDs combined with chemotherapy experienced a significantly longer MST (106 vs 51 days; P = .035) and TTP (76 vs 44 days; P = .02) compared to dogs receiving NSAIDs alone. Intact dogs and those with metastatic disease had significantly shorter MST (31 vs 90 days, P = .018 and 49 vs 109 days, P = .037, respectively); intact dogs also had significantly shorter TTP (25 vs 63 days, P = .0003). This study suggests that a combination of NSAIDs and chemotherapy may improve outcomes in canine PC. Metastatic disease and being entire negatively influenced prognosis.

Evaluation of a multi-agent chemotherapy protocol combining lomustine, procarbazine and prednisolone (LPP) for the treatment of relapsed canine non-Hodgkin high-grade lymphomas.

The standard of care treatment for canine lymphoma is multi-agent chemotherapy containing prednisolone, cyclophosphamide, vincristine and an anthracycline such as doxorubicin (CHOP) or epirubicin (CEOP). Lomustine, vincristine, procarbazine, and prednisone (LOPP) has been evaluated as a rescue, with encouraging results; however, resistance to vincristine is likely in patients relapsing on CHOP/CEOP, and this agent may enhance LOPP toxicity without improving efficacy. The aim of this study was to evaluate responses to a modified-LOPP protocol that does not include vincristine (LPP) and is administered on a 21-day cycle. Medical records of dogs with high-grade multicentric lymphoma from 2012 to 2017 were reviewed. Dogs with relapsed lymphoma that received LPP as a rescue protocol were enrolled. Response, time from initiation to discontinuation (TTD) and toxicity of LPP were assessed. Forty-one dogs were included. Twenty-five dogs (61%) responded to LPP including 12 complete responses (CR) and 13 partial responses (PR). Responders had a significantly longer TTD (P < .001) compared to non-responders with 84 days for CR and 58 days for PR. Neutropenia was documented in 20 dogs (57%): 12 grade I to II, 8 grade III to IV. Thrombocytopenia was infrequent (20%): 5 grade I to II, 2 grade III to IV. Twelve dogs developed gastrointestinal toxicity (30%): 10 grade I to II and 2 grade III. Nineteen dogs had elevated ALT (59%): 9 grade I to II, 10 grade III to IV. Treatment was discontinued due to toxicity in 8 dogs (19%). The LPP protocol shows acceptable efficacy and toxicity-profile and minimizes in-hospital procedures.

Epirubicin in the treatment of canine histiocytic sarcoma: sequential, alternating and rescue chemotherapy.

The aims of this study were to report treatment outcomes for dogs with histiocytic sarcoma (HS) treated with both lomustine and epirubicin, and to report response rates to epirubicin as a rescue therapy in dogs previously treated with lomustine. Medical records of dogs with a diagnosis of HS that were treated with both lomustine and epirubicin were retrospectively evaluated. Of 29 dogs receiving epirubicin alternating with, or subsequent to lomustine treatment, including in a rescue setting, response to epirubicin could be assessed in 20 with an overall response rate (ORR) of 29% and biological response rate (BRR) of 71%. Median time to progression (TTP) in 12 of these 20 dogs in which it was assessable was 69 days (range: 40-125 days). For dogs treated in the rescue setting epirubicin specific ORR was 19% and BRR 63%. Median TTP in the 9 of these 16 dogs in which it was assessable was 62 days (range: 40-125 days). Median survival time for all dogs treated with both epirubicin and lomustine was 185 days (range: 27-500 days). Some dogs with HS respond to epirubicin and dogs treated with combinations of epirubicin and lomustine have modestly improved survival times compared with single agent studies, and similar to dogs with HS treated with alternating lomustine and doxorubicin. Single agent epirubicin is also a valid short term rescue therapy for canine HS.

Presentation, clinical pathological and post-mortem findings in three related Scottish terriers with ligneous membranitis.

Ligneous conjunctivitis and gingivitis were diagnosed in three related Scottish terrier dogs presented for investigation of severe conjunctivitis and respiratory signs. Hypoplasminogenaemia was confirmed in one of the three affected dogs. Supportive treatment was not effective, and the dogs died or were euthanased because of the disease. Post-mortem analysis of two of the dogs revealed multiple abnormalities including severe proliferative fibrinous lesions affecting the conjunctiva, gingiva, trachea, larynx and epicardium and multiple fibrous adhesions throughout the thoracic and abdominal cavities. One dog had internal hydrocephalus and lacked a cerebellar vermis. Ligneous membranitis was confirmed on histopathology. This is a rare condition in dogs but an important differential diagnosis for severe conjunctivitis and gingivitis.

Modelling the natural history of Huntington's disease progression.

BACKGROUND: The lack of reliable biomarkers to track disease progression is a major problem in clinical research of chronic neurological disorders. Using Huntington's disease (HD) as an example, we describe a novel approach to model HD and show that the progression of a neurological disorder can be predicted for individual patients. METHODS: Starting with an initial cohort of 343 patients with HD that we have followed since 1995, we used data from 68 patients that satisfied our filtering criteria to model disease progression, based on the Unified Huntington's Disease Rating Scale (UHDRS), a measure that is routinely used in HD clinics worldwide. RESULTS: Our model was validated by: (A) extrapolating our equation to model the age of disease onset, (B) testing it on a second patient data set by loosening our filtering criteria, (C) cross-validating with a repeated random subsampling approach and (D) holdout validating with the latest clinical assessment data from the same cohort of patients. With UHDRS scores from the past four clinical visits (over a minimum span of 2 years), our model predicts disease progression of individual patients over the next 2 years with an accuracy of 89-91%. We have also provided evidence that patients with similar baseline clinical profiles can exhibit very different trajectories of disease progression. CONCLUSIONS: This new model therefore has important implications for HD research, most obviously in the development of potential disease-modifying therapies. We believe that a similar approach can also be adapted to model disease progression in other chronic neurological disorders.

Gastrointestinal toxicity after vincristine or cyclophosphamide administered with or without maropitant in dogs: a prospective randomised controlled study.

OBJECTIVES: To assess the prevalence of gastrointestinal toxicity in dogs receiving chemotherapy with vincristine and cyclophosphamide and the efficacy of maropitant citrate (Cerenia™, Zoetis) in reducing these events. METHODS: Dogs receiving chemotherapy with cyclophosphamide or vincristine were randomised to either receive maropitant or not in the period immediately after treatment and for 4 days afterwards. Owners completed a diary of adverse events following treatment. RESULTS: Adverse events occurred in 40/58 (69%) dogs in the vincristine group. Most of these adverse events were mild and included: lethargy (62%), appetite loss (43%), diarrhoea (34%) and vomiting (24%). Adverse events occurred in 34/42 (81%) dogs treated with cyclophosphamide. Most of these adverse events were mild and included: lethargy (62%), diarrhoea (36%), appetite loss (36%) and vomiting (21%). There was no difference in total clinical score, vomiting, diarrhoea, appetite loss or lethargy score between dogs treated with maropitant and non-treated dogs in either the vincristine or cyclophosphamide groups. CLINICAL SIGNIFICANCE: Chemotherapy-related side effects are frequent but usually mild in dogs receiving vincristine or cyclophosphamide. Prophylactic administration of maropitant does not reduce the frequency of adverse events and maropitant should be administered only as required for individual cases.

Presentation and management of trapped neutrophil syndrome (TNS) in UK Border collies.

Three UK bred Border collie puppies were presented for investigation of pyrexia and severe lameness with associated joint swelling. Investigations revealed neutropenia, radiographic findings suggesting metaphyseal osteopathy, and polyarthritis and all dogs were subsequently confirmed with trapped neutrophil syndrome. Clinical improvement was seen after treatment with prednisolone and antibiotics and the dogs all survived to adulthood with a good short- to medium-term outcome. Trapped neutrophil syndrome is an important differential diagnosis for young Border collie dogs in the UK presenting with pyrexia, neutropenia and musculoskeletal signs.

Late presentation of canine nasal tumours in a UK referral hospital and treatment outcomes.

OBJECTIVES: To determine the computed tomographic stage of dogs with nasal tumours in a UK referral population, and whether stage, time to referral and treatment correlates with outcome. METHODS: Retrospective review of clinical records and computed tomography scans of dogs with nasal tumours. RESULTS: Dogs (n=78) presented to a referral practice in the UK with suspected nasal tumours are presented with more late stage tumours than dogs in the USA and Japan. Length of time from initial presentation to referral did not correlate with tumour stage at diagnosis. Median survival times for radiotherapy-treated dogs in this population are equivalent to those previously reported for late stage nasal tumours. CLINICAL SIGNIFICANCE: Dogs with nasal tumours are presented late in the course of disease in the North West of England. Dogs with clinical signs consistent with a nasal tumour should have timely imaging and biopsy, in order to make prompt treatment decisions. Although survival times are comparable with previous reports and radiotherapy is a valid treatment option for dogs with late stage disease, better outcomes are likely to be achievable with earlier treatment.

Design and validation of an error capture tool for quality evaluation in the vascular and endovascular surgical theatre.

BACKGROUND: The unique and complex vascular and endovascular theatre environment is associated with significant risks of patient harm and procedural inefficiency. Accurate evaluation is crucial to improve quality. This pilot study attempted to design a valid, reproducible tool for observers and teams to identify and categorise errors. METHODS: Relevant published literature and previously collected ethnographic field notes from over 250 h of arterial surgery were analysed. A comprehensive log of vascular procedural errors was compiled and twelve vascular experts graded each error for the potential to disrupt procedural flow and cause harm. Using this multimodal approach, the Imperial College Error CAPture (ICECAP) tool was developed. The tool was validated during 21 consecutive arterial cases (52 h operating-time) as an observer-led error capture record and as a prompt for surgical teams to determine the feasibility of error self-reporting. RESULTS: Six primary categories (communication, equipment, procedure independent pressures, technical, safety awareness and patient related) and 20 error sub-categories were determined as the most frequent and important vascular procedural errors. Using the ICECAP, the number of errors detected correlated well between two observers (Spearman rho = 0.984, p < 0.001). Both observers identified all moderate or severe errors similarly and categorised all but 4/139 (2.9%) of the total errors in an identical fashion. Self-reporting of errors without prompting identified a mean of 24.4% (range 0-50%) of all recorded errors, whereas surgical teams reported a mean of 69.7% (range 50-100%) of errors when ICECAP error-category prompts were used. CONCLUSION: The ICECAP tool may be useful for capturing and categorising errors that occur during vascular/endovascular procedures. ICECAP may also have a role as an error recall prompt for self-reporting purposes by vascular surgical teams.

Imprecision when using measuring cups to weigh out extruded dry kibbled food.

Many pet cats and dogs are fed dry extruded kibbled food by measuring cup, yet the precision and accuracy of this feeding strategy is not known. Over 12 studies, we assessed precision and accuracy of weighing out food portions, of various dry kibbled foods, by measuring cup. Poor precision was noted in all studies, with intra- and inter-subject coefficients of variation ranging from 2 to 13% and 2 to 28% respectively. Variable accuracy was also noted, which ranged from an 18% under-estimate to an 80% over-estimate in portion size. No specific factors were associated with imprecision, but the degree of inaccuracy was negatively associated with portion size (R = -0.67, p = 0.022), and positively associated with the number of subjects participating in the study (R = 0.60, p = 0.048). This is the first study to document imprecision and inaccuracy of using measuring cups to estimate portions of extruded dry kibbled food. Over time, such errors could contribute to insidious weight gain in companion animals, potentially contributing to the development of obesity. Imprecision in measuring food portions could also contribute to failure of weight management programmes for obese animals.

First Report of Tobacco etch virus Infection in Coleus in the United States.

Virus-like disease symptoms consisting of foliar and veinal necrosis similar to those caused by Coleus vein necrosis virus (CVNV) (2) were observed in plants of coleus (Coleus blume Benth.) 'Rustic Orange' obtained from retail greenhouse outlets in Missouri and Minnesota. Flexuous, filamentous, 750 to 770 nm virus-like particles (vlps) were observed by transmission electron microscopy in negatively stained partially purified leaf tissue extracts from symptomatic 'Rustic Orange' leaf tissue. No other virus-like particles were observed and none were detected in extracts from asymptomatic leaves. These vlps were longer than those of CVNV (640 nm) (2) and were not detected by immunosorbent electron microscopy (ISEM) using antibodies to CVNV (2). Degenerate potyvirus primers PNIbF1 (5'GGBAAYAATAGTGGNCAACC3') and PCPR1 (5'GGGGAGGTGCCGTTCTCDATRCACCA3') (1) and total RNA extracted from 'Rustic Orange' leaf tissue with a Qiagen RNeasy Kit were used for reverse transcription-PCR with Ready-To-Go RT-PCR Beads (GE Healthcare). A 950-bp amplicon was obtained from total RNA from diseased but not from healthy leaf tissue. The nucleotide sequence of the amplicon (GenBank Accession No. GQ268818) had levels of identity to published Tobacco etch virus (TEV) sequences comprising portions of the nuclear inclusion body (NIb) and coat protein (CP) gene regions ranging from 89% (L38714) to 93% (M15239, M11458). The identity of the virus occurring in 'Rustic Orange' was further confirmed by ISEM. Virions were trapped and decorated by antibodies to TEV (ATCC PVAS 32). Systemically infected leaf tissue from Datura stramonium in which the coleus TEV isolate was propagated was used to mechanically inoculate Carborundum-dusted leaves of virus-free test plants of 'Rustic Orange' (Park Seed, Greenwood, SC). Inoculated plants developed foliar necrosis symptoms similar to those observed originally, and the presence of TEV was confirmed by ISEM and RT-PCR and nucleotide sequence analysis as described above. To our knowledge, this is the first report of a disease of coleus caused by TEV. Many of approximately 30 'Rustic Orange' plants in one nursery in Minnesota showed similar necrotic foliar symptoms and randomly selected plants tested positive for TEV by ISEM. This suggests that TEV infection in this variety may be spread by vegetative propagation from infected stock plants. References: (1) Y.-C. Hsu et al. J. Virol. Methods 128:54. 2005. (2) D. S. Mollov et al. Plant Dis. 91:754. 2007.

First Report of Tobacco rattle virus in Sedum in Minnesota.

Sedums (Sedum spp.; Crassulaceae) are perennial landscape plants that are grown widely because they are drought tolerant and winter hardy. Plants of Sedum 'Matrona' showing faint foliar ringspot symptoms were collected at a nursery retail outlet in St. Paul, MN in July 2008 and tested for possible viral infection by transmission electron microscopic (TEM) examination of negatively stained, partially purified leaf tissue extracts (1). The only virus-like particles observed were rigid, rod-shaped particles similar to those of Tobacco rattle virus (TRV) and other tobraviruses. A random sample of 100 measurements showed particles 20 nm in diameter with two modal lengths of 115 nm and 175 nm. These virus-like particles were confirmed to be those of TRV by immunosorbent electron microscopy (1) using antiserum to TRV (ATCC PVAS 75) and by reverse transcription (RT)-PCR using total RNA extracted with the RNeasy Kit (Qiagen, Valencia, CA) and primers that yield a 462-bp amplicon from TRV RNA 1 (4). An amplicon of the expected size was obtained by RT-PCR and its nucleotide sequence (GenBank Accession No. GQ268817) had 95 to 99% identity to published TRV sequences (AAW13192 and AAB48382). Two additional amplicons generated by RT-PCR from separate plants were identical in size and nucleotide sequence to the first. On the basis of virion morphology, serological relatedness, and sequence identity, the virus associated with mild ringspot symptoms in sedum was identified as an isolate of TRV. To our knowledge, this represents the first report of TRV incidence in sedum. Although Arabis mosaic virus is the only other virus reported to occur in sedum (2), we have observed numerous, flexuous filamentous 750 to 800 nm virus-like particles in partially purified extracts of a range of sedums showing mild mosaic and/or vein-clearing symptoms in Minnesota. Similar virus-like particles were not observed by TEM in partially purified extracts from TRV-infected 'Matrona' plants, suggesting that they did not contribute to the symptoms observed. We have reported previously (3) the occurrence of TRV in a variety of widely grown perennial ornamentals that provide potential sources of inoculum for spread of this virus by nematode vectors (Trichodorus and Paratrichodorus spp.) that occur commonly in garden soil, and Sedum is now added to the list of potential TRV reservoir plants. References: (1) Y. S. Ahlawat et al. Plant Dis. 80:590, 1996. (2) A. Gera et al. Acta Hortic. 722:175, 2006. (3) B. E. Lockhart et al. Plant Dis. 79:1249, 1995. (4) D. J. Robinson. J. Virol. Methods 40:57, 1992.

Expression and nephron segment-specific distribution of major renal aquaporins (AQP1-4) in Equus caballus, the domestic horse.

Aquaporins (AQPs) play fundamental roles in water and osmolyte homeostasis by facilitating water and small solute movement across plasma membranes of epithelial, endothelial, and other tissues. AQP proteins are abundantly expressed in the mammalian kidney, where they have been shown to play essential roles in fluid balance and urine concentration. Thus far, the majority of studies on renal AQPs have been carried out in laboratory rodents and sheep; no data have been published on the expression of AQPs in kidneys of equines or other large mammals. The aim of this comparative study was to determine the expression and nephron segment localization of AQP1-4 in Equus caballus by immunoblotting and immunohistochemistry with custom-designed rabbit polyclonal antisera. AQP1 was found in apical and basolateral membranes of the proximal convoluted tubules and thin descending limbs of the loop of Henle. AQP2 expression was specifically detected in apical membranes of cortical, medullary, and papillary collecting ducts. AQP3 was expressed in basolateral membranes of cortical, medullary, and papillary collecting ducts. Immunohistochemistry also confirmed AQP4 expression in basolateral membranes of cells lining the distal convoluted and connecting tubules. Western blots revealed high expression of AQP1-4 in the equine kidney. These observations confirm that AQPs are expressed in the equine kidney and are found in similar nephron locations to mouse, rat, and human kidney. Equine renal AQP proteins are likely to be involved in acute and chronic regulation of body fluid composition and may be implicated in water balance disorders brought about by colic and endotoxemia.

Expression of the GLUT1 and GLUT9 facilitative glucose transporters in embryonic chondroblasts and mature chondrocytes in ovine articular cartilage.

Glucose transport across the chondrocyte membrane is essential for chondrogenesis and the development of the skeletal system. We have previously used RT-PCR to show that fully developed human articular chondrocytes express transcripts for the GLUT1 and GLUT9 glucose transporters. In this study we report on the expression and immunohistochemical localization of the GLUT1 and GLUT9 proteins in embryonic and mature ovine cartilage. We also provide Western blot evidence for GLUT1 and GLUT9 expression in mature ovine chondrocytes. Ovine embryos (developmental stages E32 to E36 and E42 to E45) were obtained from pregnant ewes humanely killed by injection with sodium pentobarbitone. Embryos were fixed and processed for immunohistochemistry. Polyclonal antibodies to GLUT1 and GLUT9 revealed that both transporters are expressed in developing chondrocytes in ovine embryos and in the superficial, middle and deep layers of ovine cartilage from mature animals. GLUT1 expression was observed in erythrocytes and organs including heart, liver, and kidney. GLUT9 was also found in heart, kidney and liver. Western blotting confirmed the presence of the GLUT1 protein which migrated between the 50 and 64 kDa markers and two specific GLUT9 bands migrating under the 50 and 60 kDa markers, respectively. The presence of GLUT1 and GLUT9 in developing joints of ovine embryos suggests that these proteins may be important in glucose delivery to developing chondroblasts. Expression of these GLUT isoforms may be an important bioenergetic adaptation for chondrocytes in the extracellular matrix of developing cartilage.

A genetic linkage map of quinoa ( Chenopodium quinoa) based on AFLP, RAPD, and SSR markers.

Quinoa ( Chenopodium quinoa Willd.) is an important seed crop for human consumption in the Andean region of South America. It is the primary staple in areas too arid or saline for the major cereal crops. The objective of this project was to build the first genetic linkage map of quinoa. Selection of the mapping population was based on a preliminary genetic similarity analysis of four potential mapping parents. Breeding lines 'Ku-2' and '0654', a Chilean lowland type and a Peruvian Altiplano type, respectively, showed a low similarity coefficient of 0.31 and were selected to form an F(2) mapping population. The genetic map is based on 80 F(2) individuals from this population and consists of 230 amplified length polymorphism (AFLP), 19 simple-sequence repeat (SSR), and six randomly amplified polymorphic DNA markers. The map spans 1,020 cM and contains 35 linkage groups with an average marker density of 4.0 cM per marker. Clustering of AFLP markers was not observed. Additionally, we report the primer sequences and map locations for 19 SSR markers that will be valuable tools for future quinoa genome analysis. This map provides a key starting point for genetic dissection of agronomically important characteristics of quinoa, including seed saponin content, grain yield, maturity, and resistance to disease, frost, and drought. Current efforts are geared towards the generation of more than 200 mapped SSR markers and the development of several recombinant-inbred mapping populations.

A polymorphic marker for the human cathepsin B gene.

Human cathepsin B (CTSB) is a proteolytic enzyme implicated in tumor invasion and metastasis. We describe a PCR-based polymorphic marker for this gene comprising two amplimers differing in length by 19 consecutive nucleotides in intron 7, near the exon 8 splice acceptor site, identifying two gene alleles (A and B). Allele frequencies were 0.614 for A and 0.386 for the B allele, with an observed heterozygosity of 0.457 in a cohort of 70 non-related Australian blood donors. One additional nucleotide difference was also revealed through sequencing. The human CTSB gene is located on chromosome 8 and the alleles described here can potentially be used as markers in linkage and association studies of cancers and other diseases.