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Understanding the effects of cash crop expansion on natural forest is of fundamental importance. However, for most crops there are no remotely sensed global maps1, and global deforestation impacts are estimated using models and extrapolations. Natural rubber is an example of a principal commodity for which deforestation impacts have been highly uncertain, with estimates differing more than fivefold1–4. Here we harnessed Earth observation satellite data and cloud computing5to produce high-resolution maps of rubber (10 m pixel size) and associated deforestation (30 m pixel size) for Southeast Asia. Our maps indicate that rubber-related forest loss has been substantially underestimated in policy, by the public and in recent reports6–8. Our direct remotely sensed observations show that deforestation for rubber is at least twofold to threefold higher than suggested by figures now widely used for setting policy4. With more than 4 million hectares of forest loss for rubber since 1993 (at least 2 million hectares since 2000) and more than 1 million hectares of rubber plantations established in Key Biodiversity Areas, the effects of rubber on biodiversity and ecosystem services in Southeast Asia could be extensive. Thus, rubber deserves more attention in domestic policy, within trade agreements and in incoming due-diligence legislation.

The meiosis-specific kinase Mek1regulates key steps in meiotic recombination in the budding yeast, Saccharomyces cerevisiae. MEK1limits resection at double-strand break (DSB) ends and is required for preferential strand invasion into homologs, a process known as interhomolog bias. After strand invasion, MEK1promotes phosphorylation of the synaptonemal complex protein Zip1 that is necessary for DSB repair mediated by a crossover-specific pathway that enables chromosome synapsis. In addition, Mek1phosphorylation of the meiosis-specific transcription factor, Ndt80, regulates the meiotic recombination checkpoint that prevents exit from pachytene when DSBs are present. Mek1interacts with Ndt80through a 5-amino acid sequence, RPSKR, located between the DNA-binding and activation domains of Ndt80. AlphaFold Multimer modeling of a fragment of Ndt80containing the RPSKR motif and full-length Mek1indicated that RPSKR binds to an acidic loop located in the Mek1FHA domain, a noncanonical interaction with this motif. A second protein, the 5′-3′ helicase Rrm3, similarly interacts with Mek1through an RPAKR motif and is an in vitro substrate of Mek1. Genetic analysis using various mutants in the MEK1acidic loop validated the AlphaFold model, in that they specifically disrupt 2-hybrid interactions with Ndt80and Rrm3. Phenotypic analyses further showed that the acidic loop mutants are defective in the meiotic recombination checkpoint and, in certain circumstances, exhibit more severe phenotypes compared to the NDT80mutant with the RPSKR sequence deleted, suggesting that additional, as yet unknown, substrates of Mek1also bind to Mek1using an RPXKR motif.

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Preparing patients for posthospital care may improve readmission risk. Alternative payment models (APMs) incent hospitals to reduce readmissions by tying payment to outcomes. The impact of APMs on preparation for discharge is not well understood. We assessed whether patient-reported preparation for posthospital care was associated with reduced readmissions, and whether APM participation was associated with improved preparation for posthospital care. We used mixed-effects regression on retrospective (2013–2017) observational data for 2685 U.S. hospitals. We measured patient-reported preparation for posthospital care using the 3-Item Care Transition Measure and readmission using 30-day all-cause risk-adjusted readmissions from Hospital Compare. Participation in accountable care organizations (ACOs), Medical Homes, and Medicare's Bundled Payments for Care Improvement program was obtained from Medicare, the American Hospital Association's Annual Survey, and Leavitt Partner's ACO database. We found that APMs are not associated with improved preparation for posthospital care, even though it was associated with reduced readmissions (Marginal Effect: −0.012 percentage points). This may be because hospitals are not investing in patient engagement. This study has limited insight into causality and reduced generalizability among smaller, rural, and non-teaching hospitals.

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Supplemental Digital Content is available in the text.

Data supporting the efficacy of preventive pharmacological therapy (PPT) to reduce urolithiasis recurrence are based on clinical trials with composite outcomes that incorporate imaging findings and have uncertain clinical significance. This study evaluated whether the use of PPT leads to fewer symptomatic stone events.

IMPORTANCE: Indwelling urethral catheters (ie, Foley catheters) are important in caring for certain hospitalized patients but can also cause complications in patients. OBJECTIVE: To determine the incidence of infectious and noninfectious patient-reported complications associated with the indwelling urethral catheter. DESIGN, SETTING, AND PARTICIPANTS: A prospective cohort study of consecutive patients with placement of a new indwelling urethral catheter while hospitalized at 1 of 4 US hospitals in 2 states. The study was conducted from August 26, 2015, to August 18, 2017. Participants were evaluated at baseline and contacted at 14 days and 30 days after insertion of the catheter about complications associated with the indwelling urethral catheter and how catheterization affected their social activities or activities of daily living. EXPOSURES: Indwelling urethral catheter placement during hospitalization. Patients were enrolled within 3 days of catheter insertion and followed up for 30 days after catheter placement, whether the catheter remained in or was removed from the patient. MAIN OUTCOMES AND MEASURES: Infectious and noninfectious complications associated with an indwelling urethral catheter as well as how the catheter affected patient social activities or activities of daily living. RESULTS: Of 2967 eligible patients, 2227 (75.1%) agreed to participate at 1 of 4 study sites; 2076 total patients were evaluated. Of these, 71.4% were male; mean (SD) age was 60.8 (13.4) years. Most patients (1653 of 2076 [79.6%]) had short-term catheters placed for surgical procedures. During the 30 days after urethral catheter insertion, 1184 of 2076 patients (57.0%; 95% CI, 54.9%-59.2%) reported at least 1 complication due to the indwelling urethral catheter. Infectious complications were reported by 219 of 2076 patients (10.5%; 95% CI, 9.3%-12.0%), whereas noninfectious complications (eg, pain or discomfort, blood in the urine, or sense of urinary urgency) occurred in 1150 patients (55.4%; 95% CI, 53.2%-57.6%) (P < .001). Women were more likely to report an infectious complication (92 of 594 [15.5%] women vs 127 of 1482 [8.6%] men; P < .001), while men were more likely to report a noninfectious complication (869 of 1482 [58.6%] men vs 281 of 594 [47.3%] women; P < .001). Restrictions in activities of daily living (49 of 124 patients [39.5%]) or social activity (54 of 124 [43.9%]) were commonly reported by the patients who had catheters still in place; sexual problems were reported by 99 of 2034 patients (4.9%) after their catheter was removed. CONCLUSIONS AND RELEVANCE: Noninfectious complications of urethral catheters affect a substantial number of patients, underscoring the importance of avoiding urethral catheterization whenever possible. Given the high incidence of these patient-reported complications, urethral catheter–associated noninfectious complications should be a focus of surveillance and prevention efforts.

IMPORTANCE: To reduce inefficiency and waste associated with care fragmentation, many current programs target greater clinical integration among physicians. However, these programs have led to only modest Medicare spending reductions. Most programs focus on formal integration, which often bears little resemblance to actual physician interaction patterns. OBJECTIVES: To examine how physician interaction patterns vary between health systems and to assess whether variation in informal integration is associated with care delivery payments. DESIGN, SETTING, AND PARTICIPANTS: National Medicare data from January 1, 2008, through December 31, 2011, identified 253 545 Medicare beneficiaries (aged ≥66 years) from 1186 health systems where Medicare beneficiaries underwent coronary artery bypass grafting (CABG) procedures. Interactions were mapped between all physicians who treated these patients—including primary care physicians and surgical and medical specialists—within a health system during their surgical episode. The level of informal integration was measured in these networks of interacting physicians. Multivariate regression models were fitted to evaluate associations between payments for each surgical episode made on a beneficiary’s behalf and the level of informal integration in the health system where the patient was treated. EXPOSURES: The informal integration level of a health system. MAIN OUTCOMES AND MEASURES: Price-standardized total surgical episode and component payments. RESULTS: The total 253 545 study participants included 175 520 men (69.2%; mean [SD] age, 74.51 [5.75] years) and 78 024 women (34.3%; 75.67 [5.91] years). One beneficiary of the 253 545 participants did not have sex information. The low level of informal clinical integration included 84 598 patients (33.4%; mean [SD] age, 75.00 [5.93] years); medium level, 84 442 (33.30%; 74.94 [5.87] years); and high level, 84 505 (33.34%; 74.66 [5.72] years) (P < .001). Informal integration levels varied across health systems. After adjusting for patient, health-system, and community factors, higher levels of informal integration were associated with significantly lower total episode and component payments (β coefficients for informal integration were −365.87 [95% CI, −451.08 to −280.67] for total episode payments, −182.63 [−239.80 to −125.46] for index hospitalization, −43.13 [−55.53 to −30.72] for physician services, −74.48 [−103.45 to −45.51] for hospital readmissions, and −62.04 [−88.00 to −36.07] for postacute care; P < .001 for each association). When beneficiaries were treated in health systems with higher informal integration, the greatest savings of lower estimated payments were from hospital readmissions (13.0%) and postacute care services (5.8%). CONCLUSIONS AND RELEVANCE: Informal integration is associated with lower spending. Although most programs that seek to promote clinical integration are focused on health systems’ formal structures, policy makers may also want to address informal integration.

Saccharomyces cerevisiaeMek1 is a CHK2/Rad53-family kinase that regulates meiotic recombination and progression upon its activation in response to DNA double-strand breaks (DSBs). The full catalog of direct Mek1 phosphorylation targets remains unknown. Here, we show that phosphorylation of histone H3 on threonine 11 (H3 T11ph) is induced by meiotic DSBs in S. cerevisiaeand Schizosaccharomyces pombe. Molecular genetic experiments in S. cerevisiaeconfirmed that Mek1 is required for H3 T11ph and revealed that phosphorylation is rapidly reversed when Mek1 kinase is no longer active. Reconstituting histone phosphorylation in vitrowith recombinant proteins demonstrated that Mek1 directly catalyzes H3 T11 phosphorylation. Mutating H3 T11 to nonphosphorylatable residues conferred no detectable defects in otherwise unperturbed meiosis, although the mutations modestly reduced spore viability in certain strains where Rad51 is used for strand exchange in place of Dmc1. H3 T11ph is therefore mostly dispensable for Mek1 function. However, H3 T11ph provides an excellent marker of ongoing Mek1 kinase activity in vivo. Anti-H3 T11ph chromatin immunoprecipitation followed by deep sequencing demonstrated that H3 T11ph was highly enriched at presumed sites of attachment of chromatin to chromosome axes, gave a more modest signal along chromatin loops, and was present at still lower levels immediately adjacent to DSB hotspots. These localization patterns closely tracked the distribution of Red1 and Hop1, axis proteins required for Mek1 activation. These findings provide insight into the spatial disposition of Mek1 kinase activity and the higher order organization of recombining meiotic chromosomes.

IMPORTANCE: Medicare is experimenting with numerous concurrent reforms aimed at improving quality and value for hospitals. It is unclear if these myriad reforms are mutually reinforcing or in conflict with each other. OBJECTIVE: To evaluate whether hospital participation in voluntary value-based reforms was associated with greater improvement under Medicare’s Hospital Readmission Reduction Program (HRRP). DESIGN, SETTING, AND PARTICIPANTS: Retrospective, longitudinal study using publicly available national data from Hospital Compare on hospital readmissions for 2837 hospitals from 2008 to 2015. We assessed hospital participation in 3 voluntary value-based reforms: Meaningful Use of Electronic Health Records; the Bundled Payment for Care Initiative episode-based payment program (BPCI); and Medicare’s Pioneer and Shared Savings accountable care organization (ACO) programs. We used an interrupted time series design to test whether hospitals’ time-varying participation in these value-based reforms was associated with greater improvement in Medicare’s HRRP. MAIN OUTCOMES AND MEASURES: Thirty-day risk standardized readmission rates for acute myocardial infarction (AMI), heart failure, and pneumonia. RESULTS: Among the 2837 hospitals in this study, participation in value-based reforms varied considerably over the study period. In 2010, no hospitals were participating in the meaningful use, ACO, or BPCI programs. By 2015, only 56 hospitals were not participating in at least 1 of these programs. Among hospitals that did not participate in any voluntary reforms, the association between the HRRP and 30-day readmission was −0.76 percentage points for AMI (95% CI, −0.93 to −0.60), −1.30 percentage points for heart failure (95% CI, −1.47 to −1.13), and −0.82 percentage points for pneumonia (95% CI, −0.97 to −0.67). Participation in the meaningful use program alone was associated with an additional change in 30-day readmissions of −0.78 percentage points for AMI (95% CI, −0.89 to −0.67), −0.97 percentage points for heart failure (95% CI, −1.08 to −0.86), and −0.56 percentage points for pneumonia (95% CI, −0.65 to −0.47). Participation in ACO programs alone was associated with an additional change in 30-day readmissions of −0.94 percentage points for AMI (95% CI, −1.29 to −0.59), −0.83 percentage points for heart failure (95% CI, −1.26 to −0.41), and −0.59 percentage points for pneumonia (95% CI, −1.00 to −0.18). Participation in multiple reforms led to greater improvement: participation in all 3 programs was associated with an additional change in 30-day readmissions of −1.27 percentage points for AMI (95% CI, −1.58 to −0.97), −1.64 percentage points for heart failure (95% CI, −2.02 to −1.26), and −1.05 percentage points for pneumonia (95% CI, −1.32 to −0.78). CONCLUSIONS AND RELEVANCE: Hospital participation in voluntary value-based reforms was associated with greater reductions in readmissions. Our findings lend support for Medicare’s multipronged strategy to improve hospital quality and value.

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This Outlook discusses Mu et al.’s finding showing that synaptonemal complex (SC) formation between individual chromosomes provides the feedback to down-regulate Spo11 activity, thereby revealing an additional function for the SC.

We show that Ady4 is a targeting factor that recruits the lipid kinase Mss4 to the meiotic SPB in yeast. The SPB protein Spo21 binds membranes through a positively charged helix and this is essential for proper membrane formation. Ady4 recruitment of Mss4 likely alters the local membrane composition to stabilize the SPB/membrane interaction.

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Loss of VPS13produces multiple phenotypes. This study implicates VPS13in the function of membrane contact sites and suggests that different phenotypes of the mutant result from defects in different contact sites. In yeast, mutations found in the VPS13Agene of ChAc patients have specific defects in the mitochondrial aspect of VPS13function.

Background:Data from the general surgery literature suggests that patient morphometric data obtained from preoperative imaging may help predict a patient’s risk around surgery. Objectives:In this context, we evaluated for associations between psoas muscle area and short-term convalescence following radical cystectomy. Methods:After identifying patients who underwent radical cystectomy at our institution (2008 to 2013), we calculated their psoas muscle area from staging computed tomography scans using established analytic morphomic techniques. We then determined early recovery among patients with high and low psoas muscle area using the validated Convalescence and Recovery Evaluation (CARE) questionnaire—a 27-item survey, divided into four domains (activity, cognitive, gastrointestinal, and pain recovery). Finally, we assessed the relationship between psoas muscle area and changes in CARE scores with nested linear regression models. Results:Among the 86 men and among 31 women in our cohort, the median total psoas muscle area was 2,544 mm2and 1,511 mm2, respectively (P <  0.001 for the comparison). While there was no association between psoas muscle area and recovery in men, women with higher (versus lower) total psoas muscle area had smaller decreases in their pain scores postoperatively and a quicker return to their baseline level (P = 0.05). Activity scores also approached baseline levels faster among women with higher psoas muscle area, although this finding did not reach statistical significance. Conclusions:Psoas muscle area is potentially an important preoperative predictor of recovery for women undergoingradical cystectomy. More broadly speaking, analytic morphomics may represent a novel approach to better understand perioperative risk.

Compared with white patients, black patients are more likely to undergo cardiac surgery at low-quality hospitals, even when they live closer to high-quality ones. Opportunities for organizational interventions to alleviate this problem remain elusive.

There has been a strong push to move outpatient surgery from hospital settings to ambulatory surgery centers (ASCs). Despite the efficiency advantages of ASCs, many are concerned that these facilities could increase overall utilization.

There are concerns that the availability of in-office ancillary services may lower thresholds for evaluation, leading to the overuse of testing without clear benefit. Motivated by this issue, we analyzed nationally representative survey data, and examined for associations between the availability of in-office laboratory services and the use of prostate specific antigen testing.

Interstitial lung diseases (ILD), including those related to connective tissue disease (CTD), and idiopathic pulmonary fibrosis (IPF) carry high morbidity and mortality. Great efforts are under way to develop and investigate meaningful treatments in the context of clinical trials. However, efforts have been challenged by a lack of validated outcome measures and by inconsistent use of measures in clinical trials. Lack of consensus has fragmented effective use of strategies in CTD-ILD and IPF, with a history of resultant difficulties in obtaining agency approval of treatment interventions. Until recently, the patient perspective to determine domains and outcome measures in CTD-ILD and IPF had never been applied. Efforts described here demonstrate unequivocally the value and influence of patient involvement on core set development. Regarding CTD-ILD, this is the first OMERACT working group to directly address a manifestation/comorbidity of a rheumatic disease (ILD) as well as a disease not considered rheumatic (IPF). The OMERACT 11 proceedings of the CTD-ILD Working Group describe the forward and lateral process to include both the medical and patient perspectives in the urgently needed identification of a core set of preliminary domains and outcome measures in CTD-ILD and IPF.

BACKGROUND Ambulatory surgery centers (ASCs) potentially deliver care more efficiently than hospitals. However, ASC proliferation may increase discretionary surgery use because of financial incentives for the physicians who staff them. To explore this possibility, we measured the impact of the opening of an ASC in a health care market, as defined by the hospital service area (HSA), on rates of procedure use. DESIGN With a 100% sample of outpatient surgery encounters, we measured annual rates of use for discretionary (cataract surgery, colonoscopy, and upper gastrointestinal [GI] tract endoscopy) and imperative (cancer-directed breast surgery) procedures among Medicare-eligible persons. Using a multiple time series research design, we compared the change in procedure use for HSAs where ASCs opened with that of HSAs where an ASC was never present. SETTING Florida HSAs. PATIENTS All patients 65 years or older undergoing outpatient surgery from January 1, 1998, through December 31, 2006. MAIN OUTCOME MEASURE Adjusted HSA-level rates of procedure use. RESULTS In HSAs where an ASC opened, colonoscopy use increased by 1610 procedures per 100 000 per year (95% confidence interval, 736-2485; P &lt; .001) and upper GI tract endoscopy use increased by 775 procedures per 100 000 per year (159-1391; P = .01). However, rates of cancer-directed breast surgery remained flat. Among HSAs where an ASC opened, the relative increases in colonoscopy and upper GI tract endoscopy use were approximately 117% and 93% higher, respectively, 4 years after the opening compared with HSAs without ASCs. CONCLUSION The opening of an ASC within an HSA is associated with significant increases in discretionary surgery use.Arch Surg. 2011;146(2):187-193--

The medical home's success depends, in part, on the degree to which primary care physicians (PCPs) and specialists collaborate to create “medical neighborhoods” based on collective accountability. Such collaboration may require a new equilibrium in chronic disease care, with some of the routine follow-up currently provided by specialists reallocated to PCPs and their medical home teams.

A robust phylogeny for the genus Hyacinthoides(bluebells) was established using cpDNA sequences and evaluated in light of a re-assessment of morphological diversity, cytology, distribution patterns and field observations. The genus is distributed in the western Mediterranean–Atlantic region and the northern African mountains. Within this area, there is a major divide between an eastern and western clade, each of them with their own radiations, mainly in autumn-winter flowering taxa in northern Africa and spring flowering taxa in the Iberian Peninsula. We now recognise eleven taxa and one hybrid taxon, which are separated into five clades. Polyploidy is confined to the H. non-scripta–hispanicaclade with diploid and triploid taxa as well as a newly recognized tetraploid taxon. For the eleven taxa, distribution ranges, taxonomy, morphology, descriptions and a new key are presented. The nomenclatural history of the genus has been reviewed. Generitypes have been designated for HyacinthoidesHeist. ex Fabr. and EndymionDumort. and lectotypes selected for four species, three of which are combined for the first time in Hyacinthoides: H. cedretorum, H. ciliolataand H. flahaultiana. Several important questions worthy of further investigation, such as evolutionary processes and their major drivers, e.g. environmental change in the Mediterranean basin, flower morphology and associated pollinators, or sympatric versus allopatric speciation have come into sharper focus through this phylogenetic investigation.

α1-Adrenergic antagonists relieve lower urinary tract symptoms related to benign prostatic hyperplasia. 5α-Reductase inhibitors (ARIs) can halt the disease's progression. To assess whether their combined use had an additive benefit, we identified and summarized all randomized controlled trials in which the combination of an α1-adrenergic antagonist and ARI was used to treat symptomatic benign prostatic hyperplasia.

To evaluate the relationship between ownership and use of ambulatory surgical centers (ASCs).

In budding yeast, as in other eukaryotes, the Cdc7 protein kinase is important for initiation of DNA synthesis in vegetative cells. In addition, Cdc7 has crucial meiotic functions: it facilitates premeiotic DNA replication, and it is essential for the initiation of recombination. This work uses a chemical genetic approach to demonstrate that Cdc7 kinase has additional roles in meiosis. First, Cdc7 allows expression of NDT80, a meiosis-specific transcriptional activator required for the induction of genes involved in exit from pachytene, meiotic progression, and spore formation. Second, Cdc7 is necessary for recruitment of monopolin to sister kinetochores, and it is necessary for the reductional segregation occurring at meiosis I. The use of the same kinase to regulate several distinct meiosis-specific processes may be important for the coordination of these processes during meiosis.

In budding yeast, as in other eukaryotes, the Cdc7 protein kinase is important for initiation of DNA synthesis in vegetative cells. In addition, Cdc7 has crucial meiotic functions: it facilitates premeiotic DNA replication, and it is essential for the initiation of recombination. This work uses a chemical genetic approach to demonstrate that Cdc7 kinase has additional roles in meiosis. First, Cdc7 allows expression of NDT80, a meiosis-specific transcriptional activator required for the induction of genes involved in exit from pachytene, meiotic progression, and spore formation. Second, Cdc7 is necessary for recruitment of monopolin to sister kinetochores, and it is necessary for the reductional segregation occurring at meiosis I. The use of the same kinase to regulate several distinct meiosis-specific processes may be important for the coordination of these processes during meiosis.

Despite data supporting the superiority of laparoscopy over conventional surgery for donor nephrectomy, prior work reveals that this technology's adoption has been slow. However, the underlying cause for its gradual adoption remains unclear. For this reason, a multilevel analysis was conducted using a population-based cohort to evaluate the amount of variation in laparoscopic donor nephrectomy use attributable to the individual, provider, and hospital levels.

We propose in this paper to use three regions of plastid DNA as a standard protocol for barcoding all land plants. We review the other markers that have been proposed and discuss their advantages and disadvantages. The low levels of variation in plastid DNA make three regions necessary; there are no plastid regions, coding or non-coding, that evolve as rapidly as mitochondrial DNA generally does in animals. We outline two, three-region options, (1) rpoC1, rpoBand 1matKor (2) rpoC1, matKand psbA-trnHas viable markers for land plant barcoding.

Meiotic recombination differs from mitotic recombination in that DSBs are repaired using homologous chromosomes, rather than sister chromatids. This change in partner choice is due in part to a barrier to sister chromatid repair (BSCR) created by the meiosis-specific kinase, Mek1, in a complex with two other meiosis-specific proteins, Hop1 and Red1. HOP1contains two functional domains, called the N and C domains. Analysis of a point mutation that specifically inactivates the C domain (hop1-K593A) reveals that the N domain is sufficient for Hop1 localization to chromosomes and for Red1 and Hop1 interactions. The C domain is needed for spore viability, for chromosome synapsis, and for preventing DMC1-independent DSB repair, indicating it plays a role in the BSCR. All of the hop1-K593Aphenotypes can be bypassed by fusion of ectopic dimerization domains to Mek1, suggesting that the function of the C domain is to promote Mek1 dimerization. Hop1 is a DSB-dependent phosphoprotein, whose phosphorylation requires the presence of the C domain, but is independent of MEK1. These results suggest a model in which Hop1 phosphorylation in response to DSBs triggers dimerization of Mek1 via the Hop1 C domain, thereby enabling Mek1 to phosphorylate target proteins that prevent repair of DSBs by sister chromatids.

Presents a study on the molecular evolution of Begonia. Characteristics of the genera within the family Begoniaceae; Method used in obtaining the phylogeny presented in the study; Relation between Symbegonia and Begonia; Paraphyletic nature of Begonia.

A new hybrid combination is reported here between two highly divergent (and taxonomically controversial) species, A. robusta(from the basally divergent A. palustrisgroup) and A. fragrans (from the more derived A. coriophoragroup); this plant, originating from the Albufera wetlands in Mallorca, is here named A. ×albuferensisR.M. Bateman, nothosp. nov. Sequencing of nuclear ITS and plastid trnL regions, together with PCR­RFLP analysis of the ITS region, confirm the suspected parentage of the hybrid and identify A. fragransas the seed­parent. Production of this hybrid is therefore inferred to have required a minimum travel distance of ca 100 m by the pollen vector from the closest presently available pollen­parent of A. robusta. As usual in orchids, the hybrid is intermediate between its parents in the majority of the 57 morphometric characters scored, but it more closely resembles its mother in three times more characters than its father. Placing this new combination in the context of other records of hybridisation in subtribe Orchidinae provides further evidence of the genetic cohesion of the genus Anacamptis, which was recently expanded to include approximately one third of the species previously assigned to Orchis s.l.

Three meiosis-specific chromosomal components in budding yeast, Mek1, Red1, and Hop1, are required for recombination, proper segregation of homologs, and the meiotic recombination checkpoint. Mek1 is a protein kinase. Mutations that increase the size of the ATP binding pocket of Mek1 (mek1-as1) sensitize the kinase to specific small molecule inhibitors. Experiments using mek1-as1demonstrate that the requirement for Mek1 kinase activity coincides with the formation of double strand breaks (DSBs) and that this activity is necessary after DSB formation to prevent repair by DMC1-independent pathways. Contrary to previous reports, Red1 is not a substrate for Mek1. Instead, RED1is required for wild-type levels of Mek1 kinase activity. In addition, activation of Mek1 requires HOP1, the formation of Red1/Hop1 complexes and a functional Mek1 FHA domain. The requirement for RED1to produce active kinase can be bypassed by a mek1mutation that creates a constitutively active Mek1 kinase. We propose that Red1 is phosphorylated by a kinase other than MEK1and that phosphothreonines on Red1 then interact with the Mek1 FHA domain to recruit the kinase to sites of DSBs where Mek1 is activated to prevent DMC1-independent DSB repair.

The utility of EST-simple sequence repeats (EST-SSRs) was evaluated in the fern Athyrium distentifolium. From 1152 frond cDNA clones, 165 microsatellites, including di-, tri-, tetra and penta-nucleotide repeat motifs, were identified. Primer design was possible for 74 of the SSRs; subsequent screening of 10 loci on 186 individuals from six natural populations revealed between two and seven alleles per locus and expected heterozygosity (HE) estimates ranging from 0.027 to 0.809. Eight of these loci were further examined for cross-species and cross-generic amplification in other Woodsiaceae species, and polymorphic products were detected. EST-derived SSRs provide robust, informative and potentially transferable polymorphic markers suitable for biodiversity research.

Retrophyllum is a genus in the Podocarpaceae consisting of five species with a disjunct distribution in the Southern Hemisphere. Support for the monophyly of the genus, and its sister group relationship to an Afrocarpus-Nageia clade, was obtained from trnL-F sequences. Within Retrophyllum, the Melanesian species (R. minus, R. comptonii, R. vitiense) formed a monophyletic group, sister to the South American species R. rospigliosii. This topology is consistent with Gondwanan fragmentation, although the amount of nucleotide substitutions between taxa is surprisingly small for such an ancient disjunction. We were unable to distinguish between historical long distance dispersal or slow substitution rates as the source of this discrepancy. Two of the Retrophyllum species are endemic to New Caledonia; one of these (R. minus) is endangered with less than 2500 individuals remaining in the wild. The other endemic species (R. comptonii) is more widespread. We have used a combination of chloroplast RFLPs and RAPDs to assess the distinctness of these two taxa that can be difficult to distinguish using morphological characters. Both techniques provided taxon-specific markers that allowed the discrimination of the two species and the clarification of uncertain identifications. Within R. comptonii we detected evidence for intra-specific genetic differentiation corresponding to geographical isolation of populations.

Overexpression of autocrine growth factors and their receptors has been reported in many human cancers. The study of autocrine-regulated pathways using in vitro culture systems can be hindered by the presence of fetal bovine serum in culture medium. A human pancreatic cancer cell line (HPAF) was slowly weaned from its dependence on fetal bovine serum and subsequently maintained in serum-free conditions. Growth factor secretion studies showed that production of autocrine growth factors such as transforming growth factor , gastrin-releasing peptide, and insulin-like growth factor I from weaned cells increased three times compared with nonweaned cells (p< 0.01). The epidermal growth factor and gastrin-releasing peptide receptor densities were also increased in weaned cells (2 times and 2.5 times, respectively, p< 0.05). The proliferation of weaned cells cultured continuously in the same medium was significantly greater than of nonweaned cells (p< 0.05). Collectively, these data indicate that weaned pancreatic cancer cells can proliferate in the absence of serum by up-regulating autocrine pathways.

ABSTRACTIn yeast, HOP1and RED1are required during meiosis for proper chromosome segregation and the consequent formation of viable spores. Mutations in either HOP1orRED1create unique as well as overlapping phenotypes, indicating that the two proteins act alone as well as in concert with each other. To understand which meiotic processes specifically require Red1p-Hop1p hetero-oligomers, a novel genetic screen was used to identify a single-point mutation of RED1,red1-K348E, that separates Hop1p binding from Red1p homo-oligomerization. The Red1-K348E protein is stable, phosphorylated in a manner equivalent to Red1p, and undergoes efficient homo-oligomerization; however, its ability to interact with Hop1p both by two-hybrid and coimmunoprecipitation assays is greatly reduced. Overexpression of HOP1specifically suppressesred1-K348E, supporting the idea that the only defect in the protein is a reduced affinity for Hop1p. red1-K348Emutants exhibit reduced levels of crossing over and spore viability and fail to undergo chromosome synapsis, thereby implicating a role for Red1p-Hop1p hetero-oligomers in these processes. Furthermore,red1-K348Esuppresses the sae2/com1defects in meiotic progression and sporulation, indicating a previously unknown role for HOP1in the meiotic recombination checkpoint.

The taxonomy of the British elms is notoriously complicated and a satisfactory consensus classification remains elusive. This taxonomic complexity appears to be attributable to the reproductive biology of the species. Ulmus glabraHuds. reproduces sexually and its taxonomic status is widely (albeit not universally) accepted. In contrast, the suckering elms of the U. minorcomplex (U. minorMill. emend. Richens sensu latissimo) rarely reproduce by seed in Britain. Instead they perpetuate predominantly by vegetative reproduction; arguments regarding their taxonomy are legion. We have used molecular markers (RAPDs) to investigate the amounts and partitioning of clonal diversity and taxon inter-relationships in the British elms, focusing on a particularly enigmatic suckering elm, U. plotiiDruce. Our molecular data suggest that all samples of U. plotiithat precisely match the type description are ramets of a single genet, the distribution of which is attributable to human planting. Morphologically similar samples, which have many but not all of the U. plotiidiagnostic characters, do not cluster with U. plotiiwhen the RAPD data are analysed using principal coordinates analysis (PCO). Instead, they are scattered on the PCO plots throughout the broader range of variability of the U. minorcomplex. The implications of these results for the taxonomy of the British elms are discussed, and the need to combine knowledge of population structure with taxonomic pragmatism is emphasized.