Has the Expansion in Extended Criteria Deceased Donors Led to a Different Type of Delayed Graft Function and Poorer Outcomes?

OBJECTIVES: There has been considerable change in the practice of deceased kidney transplantation in the past 15 years, with more extreme phenotypes implanted. The aim of this study was to determine whether increased use of expanded criteria donors (extended criteria donors and donors after circulatory death) affected clinical outcomes, including the incidence and pattern of delayed graft function. METHODS AND MATERIALS: A retrospective analysis of 1359 renal transplants was performed over 15 years. The first 10 years of data (group 1) were compared with the subsequent 5 years (group 2). Outcomes were analyzed at 6 months and 12 months in addition to serum creatinine and patterns of delayed graft function (posttransplant times: on hemodialysis, to peak creatinine, for creatinine to half, and for creatinine to fall within 10% of baseline). RESULTS: There was a significant increase in the percentage of expanded criteria donor allografts used in group 2 with a significant increase in the incidence of delayed graft function. Despite this, serum creatinine and the incidence of biopsy-proven acute rejection had both improved in group 2. Group 2 expanded criteria donor kidneys had a significantly lower incidence of type 1 delayed graft function and a significantly higher incidence of types 3 and 4 delayed graft function. Time for creatinine to half in both groups was the best predictor of a serum creatinine <180 µmol/L at 1 year. CONCLUSION: The increased use of expanded criteria donor kidneys has led to a higher incidence of delayed graft function, but the pattern has shown that the requirement for hemodialysis has significantly reduced.

An evidence-based treatment algorithm for colorectal polyp cancers: results from the Scottish Screen-detected Polyp Cancer Study (SSPoCS).

OBJECTIVES: Colorectal polyp cancers present clinicians with a treatment dilemma. Decisions regarding whether to offer segmental resection or endoscopic surveillance are often taken without reference to good quality evidence. The aim of this study was to develop a treatment algorithm for patients with screen-detected polyp cancers. DESIGN: This national cohort study included all patients with a polyp cancer identified through the Scottish Bowel Screening Programme between 2000 and 2012. Multivariate regression analysis was used to assess the impact of clinical, endoscopic and pathological variables on the rate of adverse events (residual tumour in patients undergoing segmental resection or cancer-related death or disease recurrence in any patient). These data were used to develop a clinically relevant treatment algorithm. RESULTS: 485 patients with polyp cancers were included. 186/485 (38%) underwent segmental resection and residual tumour was identified in 41/186 (22%). The only factor associated with an increased risk of residual tumour in the bowel wall was incomplete excision of the original polyp (OR 5.61, p=0.001), while only lymphovascular invasion was associated with an increased risk of lymph node metastases (OR 5.95, p=0.002). When patients undergoing segmental resection or endoscopic surveillance were considered together, the risk of adverse events was significantly higher in patients with incomplete excision (OR 10.23, p<0.001) or lymphovascular invasion (OR 2.65, p=0.023). CONCLUSION: A policy of surveillance is adequate for the majority of patients with screen-detected colorectal polyp cancers. Consideration of segmental resection should be reserved for those with incomplete excision or evidence of lymphovascular invasion.

Genetic variation in Pythium myriotylum based on SNP typing and development of a PCR-RFLP detection of isolates recovered from Pythium soft rot ginger.

Pythium myriotylum is responsible for severe losses in both capsicum and ginger crops in Australia under different regimes. Intraspecific genomic variation within the pathogen might explain the differences in aggressiveness and pathogenicity on diverse hosts. In this study, whole genome data of four P. myriotylum isolates recovered from three hosts and one Pythium zingiberis isolate were derived and analysed for sequence diversity based on single nucleotide polymorphisms (SNPs). A higher number of true and unique SNPs occurred in P. myriotylum isolates obtained from ginger with symptoms of Pythium soft rot (PSR) in Australia compared to other P. myriotylum isolates. Overall, SNPs were discovered more in the mitochondrial genome than those in the nuclear genome. Among the SNPs, a single substitution from the cytosine (C) to the thymine (T) in the partially sequenced CoxII gene of 14 representatives of PSR P. myriotylum isolates was within a restriction site of HinP1I enzyme which was used in the PCR-RFLP for detection and identification of the isolates without sequencing. The PCR-RFLP was also sensitive to detect PSR P. myriotylum strains from artificially infected ginger without the need for isolation for pure cultures. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study of intraspecific variants of Pythium myriotylum isolates recovered from different hosts and origins based on single nucleotide polymorphism (SNP) genotyping of multiple genes. The SNPs discovered provide valuable makers for detection and identification of P. myriotylum strains initially isolated from Pythium soft rot (PSR) ginger by using PCR-RFLP of the CoxII locus. The PCR-RFLP was also sensitive to detect P. myriotylum directly from PSR ginger sampled from pot trials without the need of isolation for pure cultures.

Short- and long-term outcomes of metformin compared with insulin alone in pregnancy: a systematic review and meta-analysis.

AIM: To assess the short- and long-term maternal and fetal impact of metformin in pregnancy compared with insulin. METHODS: We performed a comprehensive literature search of MEDLINE, EMBASE, BIOSIS, Cochrane Database of Systematic Reviews and ClinicalTrials.gov. Eligible studies were randomized control trials (RCTs) or follow-up of an RCT that: (1) compared metformin with insulin in pregnancy in women with gestational diabetes mellitus or Type 2 diabetes; and (2) reported maternal or fetal outcomes of interest. Two reviewers extracted the data, evaluated study quality and calculated pooled estimates. RESULTS: Sixteen studies (n = 2165 in quantitative analysis) were included. Metformin lowered the risk of neonatal hypoglycaemia [risk ratio (RR) = 0.63; 95% confidence interval (95% CI), 0.45 to 0.87], large for gestational age babies (RR = 0.80; 95% CI, 0.64 to 0.99), pregnancy-induced hypertension (RR = 0.56; 95% CI, 0.37 to 0.85) and total maternal pregnancy weight gain [mean difference (MD) -2.07; 95% CI -2.88 to -1.27]. Metformin did not increase preterm delivery (RR = 1.18; 95% CI 0.67 to 2.07), small for gestational age babies (RR = 1.20; 95% CI, 0.67 to 2.14), perinatal mortality (RR = 0.82; 95% CI, 0.17 to 3.92) or Caesarean section (RR = 0.97; 95% CI, 0.80 to 1.19). Long-term outcome information is limited. CONCLUSIONS: Our review found that metformin had no short-term adverse effects on pregnancy, potential benefits in the neonatal period, but limited long-term follow-up information. Prior to routine use, we recommend further follow-up studies of offspring exposed to metformin in utero.

Natural History of Serum Calcium and Parathyroid Hormone Following Renal Transplantation.

BACKGROUND: Hyperparathyroidism is common in end-stage renal disease. It often persists following renal transplantation (RTx) and remains elusive to manage due to the lack of evidence base. We therefore present observational data describing the natural history and management of hypercalcemia and hyperparathyroidism following RTx. METHODS: Single-center experience of 216 adult patients undergoing kidney transplantation between January 1, 2011, and December 31, 2012. Data included calcium and parathyroid hormone (PTH) pretransplant and post-transplant at 1, 13, 26, and 52 weeks. Hyperparathyroidism management modalities were also noted. RESULTS: Persistent hyperparathyroidism (secondary/tertiary) following transplantation was observed in 71 (32.9%) patients. Mean PTH level decreased in the first 3 months post-RTx (3.95 ± 0.14 vs 3.61 ± 0.13 pmol/L; P < .01). Thereafter it remained relatively static until 1 year post-RTx (3.39 ± 0.14 pmol/L). Mean adjusted calcium level rose in the 3 months post-RTx and then remained largely unchanged until 1 year (2.39 ± 0.2 mmol/L, 2.49 ± 0.21 mmol/L, 2.47 ± 0.23 mmol/L at pretransplant, 3 months, and 12 months, respectively). Cinacalcet use pretransplant was significantly associated with reduced post-transplant hyperparathyroidism (15% vs 4.7% respectively, P = .006). There was no association between PTH (3.62 ± 4.16 mmol/L) or adjusted calcium levels (2.51 ± .17 mmol/L) at 6 months and estimated glomerular filtration rate at 1 year (r2 = 0.16 and r2 = 0.23, respectively). CONCLUSION: Tertiary hyperparathyroidism following RTx is common. However, no association was observed between either post-transplant PTH or adjusted calcium and graft function.

Wedge Versus Core Biopsy at Time Zero: Which Provides Better Predictive Value for Delayed Graft Function With the Remuzzi Histological Scoring System?

BACKGROUND: Histopathological features on time-zero renal biopsies correlate with graft outcome after renal transplantation. With increasing numbers of marginal donors, assessment of pre-implantation graft quality is essential. The clinician's choice of wedge or core biopsy is performed without evidence of efficacy or safety. This study aims to compare the information derived from wedge biopsy versus core biopsy. METHODS: Prospective evaluation of 37 wedge biopsies and 30 core biopsies was performed. Histopathological data were collected on number of glomeruli and arterioles observed, and Remuzzi scoring for glomerulosclerosis, tubular atrophy, interstitial fibrosis, and arteriolar narrowing was performed. Clinical data on delayed graft function (DGF) were also collated. Sensitivity, specificity, and positive and negative predictive values for DGF were compared. RESULTS: Patient demographics between the two cohorts were comparable. No complications of biopsies occurred; 81% of wedge biopsies versus 50% of core biopsies had >10 glomeruli (P = .01), whereas 32% of wedge biopsies and 57% of core biopsies had >2 arterioles (P = .02). Wedge biopsies were more likely to identify pathology with more glomerulosclerosis, tubular atrophy (P < .01), and interstitial fibrosis (P < .01). There was a non-significant trend toward high Remuzzi scores in wedge biopsy (22% versus 7% with Remuzzi ≥ 4; P = .12). The sensitivity and positive predictive value of Remuzzi ≥ 4 for predicting DGF was better on wedge biopsy (45.5% versus 0%; P < .01 and 62.5% versus 0%; P < .01, respectively). CONCLUSIONS: Wedge biopsies were safe and superior to core biopsies for identifying clinically significant histopathological findings on pre-implantation renal biopsy. We believe that the wedge biopsy is the method of choice for time-zero biopsies.

Green and brown bridges between weeds and crops reveal novel Diaporthe species in Australia.

Diaporthe (syn. Phomopsis) species are well-known saprobes, endophytes or pathogens on a range of plants. Several species have wide host ranges and multiple species may sometimes colonise the same host species. This study describes eight novel Diaporthe species isolated from live and/or dead tissue from the broad acre crops lupin, maize, mungbean, soybean and sunflower, and associated weed species in Queensland and New South Wales, as well as the environmental weed bitou bush (Chrysanthemoides monilifera subsp. rotundata) in eastern Australia. The new taxa are differentiated on the basis of morphology and DNA sequence analyses based on the nuclear ribosomal internal transcribed spacer region, and part of the translation elongation factor-1α and ß-tubulin genes. The possible agricultural significance of live weeds and crop residues ('green bridges') as well as dead weeds and crop residues ('brown bridges') in aiding survival of the newly described Diaporthe species is discussed.

Outcomes of renal transplantation in patients with major lower limb amputation.

INTRODUCTION: The impact of severe peripheral vascular disease on graft survival in patients undergoing renal transplantation is poorly defined. The aim of our study is to establish outcomes in renal transplant recipients who have severe peripheral vascular disease necessitating major lower limb amputation. METHODS: Data for patients undergoing renal transplantation from January 2001-December 2010 was extracted from a regional transplantation database. Patients undergoing lower limb amputation pre- and post-transplantation were identified and outcome measures including delayed graft function, biopsy-proven acute rejection, serum creatinine level at 1 year, and graft loss and recipient survival at 1 year and long-term were compared with patients who did not undergo amputation. Student t and Pearson's chi-squared tests were used to compare patients with and without amputation and Kaplan-Meier curves were used for survival analysis. A P value < .05 is considered statistically significant. RESULTS: A total of 762 patients underwent renal transplantation. Four (0.5%) patients had an amputation before transplantation and 16 (2.1%) underwent amputation after transplantation. Serum creatinine levels at 1 year were significantly higher in patients who had amputation after transplantation (308.5 ± 60.8 µmol/l vs 177.6 ± 6.4 µmol/l; P = .03). During longer follow-up (mean: 2053.1 ± 58.3 days), patients who underwent amputation after transplantation had a higher rate of graft loss (P < .01) and higher death rate (P < .01). CONCLUSION: The requirement for amputation after renal transplantation is associated with poor long-term graft and patient survival and higher serum creatinine levels at 1 year. Patients at increased risk of severe peripheral vascular disease should be identified and measures taken to reduce the long-term risk.

The impact of socioeconomic deprivation on outcomes following renal transplantation in the West of Scotland.

BACKGROUND: Social deprivation is associated with increased mortality for patients on renal replacement therapy. Patients from lower socioeconomic categories have reduced access to transplantation. However, the impact of social deprivation on outcomes following renal transplantation is unknown. METHODOLOGY: We undertook a retrospective analysis of all patients undergoing renal transplantation at a single center serving the West of Scotland over the 10-year period 2000 to 2010 (n = 705). Postcode data permitted calculation of a Scottish Index of Multiple Deprivation (SIMD) score, which was analyzed in quartiles from 0% to 25% (least deprived) to 75% to 100% (most deprived). Outcomes measures were graft loss, mortality, creatinine at 1 year, delayed graft function (DGF), and biopsy-proven acute rejection (BPAR). Kaplan-Meier survival analysis was undertaken (P < .05 is significant). Results are presented as percentages of the total population in SIMD quartiles 0% to 25%, 25% to 50%, 50% to 70%, and 75% to 100%, respectively. RESULTS: Mean follow-up was 5.86 ± 0.11 years. There was no difference in survival following renal transplantation depending on SIMD (89.6%, 87%, 88.4%, 90.2%; P = .82). There was improved graft survival in the least socioeconomically deprived; however, this was not significant (80%, 69.9%, 74.1%, 73.8%; P = .34). Similarly, there was a nonsignificant trend toward lower creatinine at 1 year in the least deprived patients (163.5 ± 12.8, 211.7 ± 19.5, 170.2 ± 9.8, 197.1 ± 6.9; P = .07). There was no difference in rates of DGF (P = .47), primary nonfunction (P = .17), or BPAR (P = .97) depending on socioeconomic status. The proportion of patients undergoing living donor transplantation was similar across the range of SIMD (23.9%, 27.6%, 25.5%, 21.8%; P = .76). CONCLUSIONS: Social deprivation does not affect either graft or patient survival after renal transplantation. Additionally, it did not influence the rate of living donor renal transplantation in our patient population.

Acute kidney injury: outcomes and quality of care.

BACKGROUND: Deficiencies in management have been highlighted as contributory factors in the death of many patients with acute kidney injury (AKI). However, there is little evidence addressing the quality of care provided to patients with milder AKI. AIM: The aim of this study is to evaluate the quality of care provided to a non-select cohort of patients with AKI and evaluate discrepancies in causation, recognition and management. DESIGN: Retrospective inception cohort study. METHODS: Demographic data were collected for all 1577 patients admitted to a University Teaching Hospital during a 1-month period. Baseline, admission and peak creatinine were correlated with mortality and length of hospital admission. AKI was classified according to Kidney Disease Improving Global Outcomes criteria. A retrospective case note review of all patients with AKI was carried out to evaluate quality of documentation and clinical management of AKI. Multivariate analysis was undertaken to determine risk factors for AKI. RESULTS: Incidence of AKI on admission was 4.6%. A further 10.3% developed AKI while in hospital. All cause mortality was 4-fold higher among patients with AKI compared with those without (19 vs. 3.8%; P < 0.001). Mortality was significantly higher in those patients who developed AKI while an in-patient compared with those with AKI on admission (27.3 vs. 11.8%; P < 0.001). Diabetes, clinician perception of frailty, age and treatment with angiotensin-converting enzyme inhibitor prior to admission were found to be independent risk factors for AKI. AKI was unrecognized in 23.5% of patients, two-thirds of whom were discharged without resolution of renal function. Significant weaknesses in management were poorly kept fluid balance charts (48.2%), failure to withhold nephrotoxic drugs (38.8%) and failure to act upon abnormal biochemistry (41%) in a timely fashion. CONCLUSION: AKI is common in hospitalized patients and associated with a significant increase in hospital stay and mortality. AKI is often found in conjunction with other organ failure and in many cases is not preventable. Nevertheless clinicians need to be more vigilant of small creatinine rises to permit early intervention particularly among elderly and frail patients.

Below-target postoperative arterial blood pressure but not central venous pressure is associated with delayed graft function.

Delayed graft function (DGF) is a major issue in kidney transplantation and is associated with reduced graft and patient survival. The condition results from the summative effects of multiple injurious processes associated with transplantation with many underlying factors being nonmodifiable. Reducing cold ischemic time and machine perfusion have decreased the DGF incidence but peri-/postoperative injury resulting from suboptimal perfusion may also be critical to the development of DGF. We investigated the effect of perfusion parameters and other key variables on the incidence of DGF in 149 consecutive renal transplants. The occurrence of any recorded subtarget (70 mm Hg) mean arterial pressure (MAP) was significantly associated with DGF (perioperative P = .005; postoperative P = .002) while the occurrence of a subtarget (8 cm H(2)O) central venous pressure (CVP) among other variables was not. Routine continuous blood pressure monitoring is rare postoperatively and is shown to be more accurate than CVP in assessing renal perfusion and guiding management in the postoperative period.

The prognostic significance of iliac vessel calcification in renal transplantation.

BACKGROUND: Peripheral vascular disease and major extremity amputation are common in patients with established renal failure and are associated with considerable morbidity. Several studies have shown high rates of amputation following simultaneous pancreas-kidney transplantation, but there is minimal literature on the incidence of amputation following renal transplantation. Furthermore, there is little evidence regarding the best method of predicting which patients might be at risk of developing peripheral vascular complications after transplantation. METHODS: We undertook a 5 year follow-up on the cohort of patients who were on our renal transplant waiting list 5 years ago (January 2007). At this time, it was standard practice within our unit for all patients to have routine pelvic x-rays to assess for vascular calcification of the iliac vessels at the time of activation onto the transplant waiting list. Any patients with moderate/severe calcification on x-ray, which may complicate transplantation, were referred for computed tomography angiogram (CTA) of their aorto-iliac vessels. Mortality, transplantation outcomes, and amputation rates at 5 years were correlated with the severity of calcification on preoperative imaging. RESULTS: One hundred eighty-seven patients were on the waiting list for renal transplantation in January 2007 (92 men; mean age, 58.3 +/- 6.2 years). Ninety-three patients received a transplant during the subsequent 5 years. By January 2012, 82 patients had a functioning transplant, 45 remained on the waiting list (5 suspended), 40 patients had died, and 20 were alive but no longer on the waiting list. Seventy-three (39.5%) had moderate or severe calcification on plain x-ray and went on to have CTA. Of these patients, 16 (21.9%) had extensive calcification affecting all the iliac vessels and were removed from the waiting list as a result. Preoperative imaging was useful in determining the side for surgery in a further 18 patients (24.3%). Twenty-two patients developed vascular complications. Nineteen (86.4%) had moderate-severe vascular calcification on imaging. Four of the patients with vascular complications (18.2%) underwent transplantation (2 had below knee amputation (BKA) prior to transplantation; 1 developed distal ischemia on the same side as the transplantation 2 years postoperatively; 1 had bilateral above knee amputation (AKA) approximately 2 years after transplantation). Eleven (50%) of the patients with vascular complications were dead at 5 years of follow-up. Mortality and amputation rates were higher in patients with moderate-severe calcification than minimal calcification (30.1% vs 16.6%; P = .02 and 10.9% vs 1.8%; P = .003, respectively). There was no difference in rates of delayed graft function (DGF), biopsy-proven acute rejection (BPAR), or creatinine at 1 year between patients who underwent transplantation with moderate-severe calcification and those without, however, intraoperative vascular complications (26.7% vs 3%; P < .001), graft loss (28.1% vs 3.4%; P = .01), and death with a functioning transplant (9.7% vs 1.6%; P = .04) rates were higher in patients with extensive calcification compared with those without. CONCLUSIONS: Plain x-ray of the pelvis is a useful screening tool to identify those patients who may require further detailed vascular imaging prior to transplantation. Amputation rates following renal transplantation are low and peripheral vascular disease (PVD) in isolation should not preclude transplantation. Nevertheless, significant vascular calcification is predictive of mortality both with and without transplantation and graft loss in patients with a renal transplant.

Stem cankers on sunflower (Helianthus annuus) in Australia reveal a complex of pathogenic Diaporthe (Phomopsis) species.

The identification of Diaporthe (anamorph Phomopsis) species associated with stem canker of sunflower (Helianthus annuus) in Australia was studied using morphology, DNA sequence analysis and pathology. Phylogenetic analysis revealed three clades that did not correspond with known taxa, and these are believed to represent novel species. Diaporthe gulyae sp. nov. is described for isolates that caused a severe stem canker, specifically pale brown to dark brown, irregularly shaped lesions centred at the stem nodes with pith deterioration and mid-stem lodging. This pathogenicity of D. gulyae was confirmed by satisfying Koch's Postulates. These symptoms are almost identical to those of sunflower stem canker caused by D. helianthi that can cause yield reductions of up to 40 % in Europe and the USA, although it has not been found in Australia. We show that there has been broad misapplication of the name D. helianthi to many isolates of Diaporthe (Phomopsis) found causing, or associated with, stem cankers on sunflower. In GenBank, a number of isolates had been identified as D. helianthi, which were accommodated in several clades by molecular phylogenetic analysis. Two less damaging species, D. kochmanii sp. nov. and D. kongii sp. nov., are also described from cankers on sunflower in Australia.

RGD-ligand mimetic antagonists of integrin alphaIIbbeta3 paradoxically enhance GPVI-induced human platelet activation.

BACKGROUND: The integrin alpha(IIb)beta(3) is the major mediator of platelet aggregation and has, therefore, become an important target of antithrombotic therapy. Antagonists of alpha(IIb)beta(3), for example abciximab, tirofiban and eptifibatide, are used in the treatment of acute coronary syndromes. However, in addition to effective blockade of the integrin, binding of can induce conformational changes in the integrin and can also induce integrin clustering. This class effect of RGD-ligand mimetics might, therefore, underlie paradoxical platelet activation and thrombosis previously reported. OBJECTIVES: To examine the components of signaling pathways and functional responses in platelets that may underlie this phenomenon of paradoxical platelet activation. METHODS: We assessed the effect of lotrafiban, and other alpha(IIb)beta(3) antagonists including the clinically used drug tirofiban, on tyrosine phosphorylation of key signaling proteins in platelets by immunoblotting and also platelet functional outputs such as cytosolic calcium responses, phosphatidylserine exposure (pro-coagulant activity) and dense granule release. RESULTS: In all cases, no effect of alpha(IIb)beta(3) antagonists were observed on their own, but these integrin antagonists did lead to a marked potentiation of glycoprotein VI (GPVI)-associated FcR gamma-chain phosphorylation, activation of Src family kinases and Syk kinase. This correlated with increased dense granule secretion, cytosolic calcium response and exposure of phosphatidylserine on the platelet surface. P2Y(12) antagonism abolished the potentiated phosphatidylserine exposure and dense granule secretion but not the cytosolic calcium response. CONCLUSIONS: These data provide a mechanism for enhancement of platelet activity by alpha(IIb)beta(3) inhibitors, but also reveal a potentially important signaling pathway operating from the integrin to GPVI signaling.

QTL analysis of ergot resistance in sorghum.

Sorghum ergot, caused predominantly by Claviceps africana Frederickson, Mantle, de Milliano, is a significant threat to the sorghum industry worldwide. The objectives of this study were firstly, to identify molecular markers linked to ergot resistance and to two pollen traits, pollen quantity (PQ) and pollen viability (PV), and secondly, to assess the relationship between the two pollen traits and ergot resistance in sorghum. A genetic linkage map of sorghum RIL population R931945-2-2 x IS 8525 (resistance source) was constructed using 303 markers including 36 SSR, 117 AFLP , 148 DArT and two morphological trait loci. Composite interval mapping identified nine, five, and four QTL linked to molecular markers for percentage ergot infection (PCERGOT), PQ and PV, respectively, at a LOD >2.0. Co-location/linkage of QTL were identified on four chromosomes while other QTL for the three traits mapped independently, indicating that both pollen and non pollen-based mechanisms of ergot resistance were operating in this sorghum population. Of the nine QTL identified for PCERGOT, five were identified using the overall data set while four were specific to the group data sets defined by temperature and humidity. QTL identified on SBI-02 and SBI-06 were further validated in additional populations. This is the first report of QTL associated with ergot resistance in sorghum. The markers reported herein could be used for marker-assisted selection for this important disease of sorghum.

First Report of Pythium splendens Associated with Severe Wilt of Muskmelon (Cucumis melo) in Oman.

Muskmelon (Cucumis melo L.) is one of the most important vegetable crops in Oman. In the fall of 2004, sudden wilt was observed in muskmelon grown in a field at Sultan Qaboos University, Muscat. The disease was characterized by rapid collapse of vines and muskmelon plants at the fruit production to maturation stage, associated with brown-to-dark brown rotted primary and secondary roots. The disease resulted in death of more than 85% of muskmelon plants in that field. On potato dextrose agar (PDA), with published methods (1), Pythium spp. were consistently isolated from crowns and roots of plants showing wilt symptoms. Further identification of five isolates of Pythium with sequences of the internal transcribed spacer (ITS) of the ribosomal DNA (1) using ITS1 and ITS4 primers produced a nucleotide sequence 806 bp long, which was identical among all isolates. Comparison with sequences deposited at the National Center for Biotechnology Information revealed 100% nucleotide similarity to a previously published sequence (Accession No. DQ381808) of isolate P091 of P. splendens from cucumber from Oman, for which identification has also been confirmed by morphological characteristics. The sequence of one isolate of P. splendens (P222) was assigned GenBank Accession No. EF546436 and deposited at CBS under Accession No. CBS121855. In pathogenicity tests conducted in a greenhouse, P. splendens induced damping-off symptoms on 7-day-old muskmelon seedlings and also reproduced the same wilt symptoms observed in the field when 2-month-old muskmelon plants were inoculated with 3-day-old P. splendens grown in PDA. To our knowledge, this is the first report of association of P. splendens with wilt of muskmelon in Oman. Reference: (1) A. M. Al-Sa'di et al. Plant Pathol. 56:140, 2007.

First Report of Glomerella cingulata (Colletotrichum gloeosporioides) Causing Anthracnose and Tip Dieback of Lygodium microphyllum and L. japonicum in Australia.

The Old World climbing fern, Lygodium microphyllum (Cav.) R. Br., and Japanese climbing fern, L. japonicum (Thunb.) Sw., are invasive noxious weeds in Florida (1). Exploratory surveys for classical biological control agents of L. microphyllum in the fern's native range of Australia and Asia have focused on aboveground herbivores (1). From February to August 2006, fungi were isolated from symptomatic foliage, including lesions associated with leaf curls caused by the mite Flocarus perrepae Knihinicki & Boczek., obtained from L. microphyllum at sites across southeast Queensland, Australia and from both fern species grown at the CSIRO Long Pocket Laboratories in Brisbane, Australia. Anthracnose symptoms with chlorotic margins, initiating at the tip or base of the individual pinnules, were observed on fronds. Dieback symptoms affected growing tips, with sunken lesions and a gradual necrotic wilt as far as the next growth junction of pinnae. Sections from diseased margins were surface sterilized, placed onto water agar, and incubated at 23°C with a 16-h photoperiod. Variable colonies of white-to-gray mycelia, felted or tufted with complete margins, grew well on oatmeal agar and potato dextrose agar. Conidia were hyaline to light salmon, aseptate, straight, and cylindrical (10.4 to 18.2 × 2.6 to 5.2 µm), borne in salmon-to-bright orange masses at 25°C, and consistent with previous descriptions of Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. (3), anamorph of Glomerella cingulata (2). Asci that formed after 3 to 4 weeks in culture were eight-spored, clavate to cylindrical (46.8 to 62.4 × 9.1 to 11.7 µm), and thickened at the apex, and ascospores were cylindrical (11.7 to 18.2 × 3.9 to 5.2 µm), slightly curved, unicellular and hyaline, which is consistent with descriptions of G. cingulata (2). No fruiting bodies were observed in planta; acervuli, setae, and perethecia were not observed. Identification was further confirmed by molecular analysis using the primer pair ITS1/ITS4 (4) (GenBank Accession No. EU697014), indicating 100% similarity to isolates of G. cingulata. To confirm pathogenicity, Koch's postulates were performed on three plants of L. japonicum and 12 plants of L. microphyllum, with an equal number of controls. Conidial suspensions were made to 1.7 × 106 conidia ml-1. During the experiments in the glasshouse, temperatures ranged from 12.6 to 40°C and relative humidity from 39 to 85%. Tips and fronds were collected after 2 to 8 weeks and isolation and identification performed. G. cingulata was consistently reisolated from diseased tissue. No symptoms appeared on controls and isolations did not yield the pathogen. To our knowledge, this is the first report of G. cingulata infecting L. microphyllum and L. japonicum in Australia. Its potential as a biological control agent in the ferns' introduced range remains to be tested. References: (1) J. A. Goolsby et al. Biol. Control. 28:33, 2003. (2) J. E. M. Mordue. Glomerella cingulata. No. 315 in: CMI Descriptions of Pathogenic Fungi and Bacteria. CAB, Kew, UK, 1971. (3) B. C. Sutton. The Genus Glomerella and its Anamorph Colletotrichum. In: Colletotrichum: Biology, Pathology and Control. J. A. Bailey and M. J. Jeger, eds. CAB International, Wallingford, UK, 1992. (4) T. M. White et al. Amplification and Direct Sequencing of Fungal Ribosomal RNA for Phylogenetics. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, 1990.

The normal human myometrium has a vascular spatial gradient absent in small fibroids.

BACKGROUND: The human uterine vasculature is highly structured, exhibiting circumferential and radial branching. Previously published angiograms of the arterial network describe a system of regular coils. Uterine fibroids lack this structured vasculature. In this study, we make a comparison between the vasculature in normal myometrium and in fibroids using robust stereological methods thus far lacking in the literature. METHODS: Stereological and morphometric analysis of the vascular system was carried out on 15 normal and 27 small fibroid (5-40 mm) uteri taken from women suffering menorrhagia. Projected images of published angiograms were also re-examined, measuring tortuosity. RESULTS: A decreasing gradient of vascular smooth muscle from outer to inner myometrium was found in normal uteri, with no corresponding gradient in capillary tissue fraction. An association between vascular luminal size, amplitude and frequency of vessel bending was also established. Conversely, fibroids were found to lack structured or muscularized vasculature. CONCLUSIONS: A quantitative gradient within the myometrial vascular system, which is absent in fibroids, has been demonstrated. These structural differences between diseased and healthy tissues are probably because of differing expression of angiogenic growth factors and may explain the distribution of particles seen after uterine artery embolization.