GDF15 linked to maternal risk of nausea and vomiting during pregnancy.

GDF15, a hormone acting on the brainstem, has been implicated in the nausea and vomiting of pregnancy, including its most severe form, hyperemesis gravidarum (HG), but a full mechanistic understanding is lacking1-4. Here we report that fetal production of GDF15 and maternal sensitivity to it both contribute substantially to the risk of HG. We confirmed that higher GDF15 levels in maternal blood are associated with vomiting in pregnancy and HG. Using mass spectrometry to detect a naturally labelled GDF15 variant, we demonstrate that the vast majority of GDF15 in the maternal plasma is derived from the feto-placental unit. By studying carriers of rare and common genetic variants, we found that low levels of GDF15 in the non-pregnant state increase the risk of developing HG. Conversely, women with ß-thalassaemia, a condition in which GDF15 levels are chronically high5, report very low levels of nausea and vomiting of pregnancy. In mice, the acute food intake response to a bolus of GDF15 is influenced bi-directionally by prior levels of circulating GDF15 in a manner suggesting that this system is susceptible to desensitization. Our findings support a putative causal role for fetally derived GDF15 in the nausea and vomiting of human pregnancy, with maternal sensitivity, at least partly determined by prepregnancy exposure to the hormone, being a major influence on its severity. They also suggest mechanism-based approaches to the treatment and prevention of HG.

Fetally-encoded GDF15 and maternal GDF15 sensitivity are major determinants of nausea and vomiting in human pregnancy.

Human pregnancy is frequently accompanied by nausea and vomiting that may become severe and life-threatening, as in hyperemesis gravidarum (HG), the cause of which is unknown. Growth Differentiation Factor-15 (GDF15), a hormone known to act on the hindbrain to cause emesis, is highly expressed in the placenta and its levels in maternal blood rise rapidly in pregnancy. Variants in the maternal GDF15 gene are associated with HG. Here we report that fetal production of GDF15, and maternal sensitivity to it, both contribute substantially to the risk of HG. We found that the great majority of GDF15 in maternal circulation is derived from the feto-placental unit and that higher GDF15 levels in maternal blood are associated with vomiting and are further elevated in patients with HG. Conversely, we found that lower levels of GDF15 in the non-pregnant state predispose women to HG. A rare C211G variant in GDF15 which strongly predisposes mothers to HG, particularly when the fetus is wild-type, was found to markedly impair cellular secretion of GDF15 and associate with low circulating levels of GDF15 in the non-pregnant state. Consistent with this, two common GDF15 haplotypes which predispose to HG were associated with lower circulating levels outside pregnancy. The administration of a long-acting form of GDF15 to wild-type mice markedly reduced subsequent responses to an acute dose, establishing that desensitisation is a feature of this system. GDF15 levels are known to be highly and chronically elevated in patients with beta thalassemia. In women with this disorder, reports of symptoms of nausea or vomiting in pregnancy were strikingly diminished. Our findings support a causal role for fetal derived GDF15 in the nausea and vomiting of human pregnancy, with maternal sensitivity, at least partly determined by pre-pregnancy exposure to GDF15, being a major influence on its severity. They also suggest mechanism-based approaches to the treatment and prevention of HG.

Species discovery and diversity in Lobocriconema (Criconematidae: Nematoda) and related plant-parasitic nematodes from North American ecoregions.

There are many nematode species that, following formal description, are seldom mentioned again in the scientific literature. Lobocriconema thornei and L. incrassatum are two such species, described from North American forests, respectively 37 and 49 years ago. In the course of a 3-year nematode biodiversity survey of North American ecoregions, specimens resembling Lobocriconema species appeared in soil samples from both grassland and forested sites. Using a combination of molecular and morphological analyses, together with a set of species delimitation approaches, we have expanded the known range of these species, added to the species descriptions, and discovered a related group of species that form a monophyletic group with the two described species. In this study, 148 specimens potentially belonging to the genus Lobocriconema were isolated from soil, individually measured, digitally imaged, and DNA barcoded using a 721 bp region of cytochrome oxidase subunit 1 (COI). One-third of the specimens were also analyzed using amplified DNA from the 3' region of the small subunit ribosomal RNA gene (18SrDNA) and the adjacent first internal transcribed spacer (ITS1). Eighteen mitochondrial haplotype groups, falling into four major clades, were identified by well-supported nodes in Bayesian and maximum likelihood trees and recognized as distinct lineages by species delimitation metrics. Discriminant function analysis of a set of morphological characters indicated that the major clades in the dataset possessed a strong morphological signal that decreased in comparisons of haplotype groups within clades. Evidence of biogeographic and phylogeographic patterns was apparent in the dataset. COI haplotype diversity was high in the southern Appalachian Mountains and Gulf Coast states and lessened in northern temperate forests. Lobocriconema distribution suggests the existence of phylogeographic patterns associated with recolonization of formerly glaciated regions by eastern deciduous forest, but definitive glacial refugia for this group of plant parasitic nematodes have yet to be identified. Unlike agricultural pest species of plant-parasitic nematodes, there is little evidence of long-distance dispersal in Lobocriconema as revealed by haplotype distribution. Most haplotype groups were characterized by low levels of intragroup genetic variation and large genetic distances between haplotype groups. The localization of nematode haplotypes together with their characteristic plant communities could provide insight into the historical formation of these belowground biotic communities.

Labor induction utilizing the Foley balloon: a randomized trial comparing standard placement versus immediate removal.

OBJECTIVE: To compare time to delivery between two induction procedures. The Foley balloon is a mechanical method for cervical ripening. However, the device may also result in endogenous prostaglandin release following separation of the chorionic membrane and decidua. Prolonged Foley placement may therefore be unnecessary for successful labor induction. METHOD: Randomized controlled trial of labor induction at LAC+USC Medical Center between 2010 and 2013. Subjects were assigned to either (a) standard placement of the Foley balloon or (b) Foley balloon insufflation and immediate removal. Oxytocin was administered to all subjects not in active labor after 12 h. Delivery information and neonatal outcomes were documented and all patients were followed for 6 weeks for adverse events. RESULT: A total of 79 women were included in the analysis (37 standard and 42 immediate). Induction time was 8.6 h longer in the immediate removal group (23.5 vs 32.1, P=0.002), but the difference in delivery within 24 h did not meet the statistical significance (46.0 vs 28.6%, P=0.11). Similar rates of cesarean delivery, epidural use and abnormal APGAR scores were observed. After controlling for number of vaginal exams and duration of rupture, a decreased risk of infection was observed in the immediate removal group (odds ratio=0.08, 95% confidence interval=0.007 to 0.93, P=0.04). Further, when the analysis was stratified by parity, differences in induction time only persisted in nulliparous women. CONCLUSION: Immediate removal of the Foley balloon may lead to longer overall induction time, but a lower risk of infection. Parous women may be particularly good candidates for this type of induction.

COI haplotype groups in Mesocriconema (Nematoda: Criconematidae) and their morphospecies associations.

Without applying an a priori bias for species boundaries, specimen identities in the plant-parasitic nematode genus Mesocriconema were evaluated by examining mitochondrial COI nucleotide sequences, morphology, and biogeography. A total of 242 specimens that morphologically conformed to the genus were individually photographed, measured, and amplified by a PCR primer set to preserve the linkage between specimen morphology and a specific DNA barcode sequence. Specimens were extracted from soil samples representing 45 locations across 23 ecoregions in North America. Dendrograms constructed by neighbor-joining, maximum likelihood, and Bayesian Inference using a 721-bp COI barcode were used to group COI haplotypes. Each tree-building approach resulted in 24 major haplotype groups within the dataset. The distinctiveness of these groups was evaluated by node support, genetic distance, absence of intermediates, and several measures of distinctiveness included in software used for the exploration of species boundaries. Five of the 24 COI haplotype groups corresponded to morphologically characterized, Linnaean species. Morphospecies conforming to M. discus, Discocriconemella inarata, M. rusticum, M. onoense, and M. kirjanovae were represented by groups composed of multiple closely related or identical COI haplotypes. In other cases, morphospecies names could be equally applied to multiple haplotype groups that were genetically distant from each other. Identification based on morphology alone resulted in M. curvatum and M. ornatum species designations applied to seven and three groups, respectively. Morphological characters typically used for species level identification were demonstrably variable within haplotype groups, suggesting caution in assigning species names based on published compendia that solely consider morphological characters. Morphospecies classified as M. xenoplax formed a monophyletic group composed of seven genetically distinct COI subgroups. The species Discocriconemella inarata is transferred to Mesocriconema inaratum based on its phylogenetic position on the COI tree as well as previous phylogenetic analyses using 18S, ITS1, and cytochrome b nucleotide sequences. This study indicates that some of the species considered cosmopolitan in their distribution are actually multispecies polyphyletic groupings and an accurate assessment of Mesocriconema species distributions will benefit from molecular determination of haplotype relationships. The groups revealed by COI analysis should provide a useful framework for the evaluation of additional Mesocriconema species and will improve the reliability of designating taxonomic units in studies of nematode biodiversity. 

No increased risk of psychological/behavioral disorders in siblings of women with hyperemesis gravidarum (HG) unless their mother had HG.

Hyperemesis gravidarum (HG), severe nausea and vomiting of pregnancy, is characterized by prolonged maternal stress, undernutrition and dehydration. Maternal stress and malnutrition of pregnancy are linked to poor neonatal outcome and associated with poor adult health, and we recently showed that in utero exposure to HG may lead to increased risks of psychological and behavioral disorders in the offspring. In addition, we have shown familial aggregation of HG, which is strong evidence for a genetic component to the disease. In this study, we compare the rates of psychological and behavioral disorders in 172 adults with and 101 adults without a sibling with HG. The rate of emotional/behavioral disorders is identical (15%) in both groups. The results suggest that the etiology of HG is not likely to include genetic factors associated with emotional and behavioral disorders. In addition, this study provides evidence that the increased incidence of psychological/behavioral disorders among offspring of women with HG is attributable to the HG pregnancy itself, rather than to confounding genetic factors linked to HG.

Neonatal outcomes of twins according to birth order, presentation and mode of delivery: a systematic review and meta-analysis.

BACKGROUND: The optimal mode of delivery for twins is undetermined. OBJECTIVE: To review literature regarding the neonatal outcomes following twin delivery. DATA SOURCES: Searches were conducted in PubMed, Medline, Embase, Cochrane library and reference lists. SELECTION CRITERIA: Studies selection criteria were: both twins alive at labour, outcomes stratified for birth order, presentation, planned and actual delivery mode. Eighteen articles were included in the meta-analysis (39, 571 twin sets). DATA COLLECTION AND ANALYSIS: The Meta-analysis of Observational Studies in Epidemiology guidelines were followed. Interstudy heterogeneity (I(2) ) was tested. A fixed model was generated whenever I(2)<25%. Pooled odds ratios (OR) with 95% CI were computed. Intergroup comparison was significant if 95% CI did not encompass 1. The first and second twins were indicated as Twin A (TA) and Twin B (TB), respectively. MAIN RESULTS: Neonatal morbidity was lower in TA than TB (3.0 versus 4.6%; OR 0.53; 95% CI 0.39-0.70). TA experienced neonatal death less often than TB (0.3 versus 0.6%; OR 0.55; 95% CI 0.38-0.81). No differences were noted between vertex and non-vertex and attempted vaginal delivery versus planned caesarean section in either TA or TB. In TA, neonatal morbidity was lower after vaginal delivery (1.1%) than caesarean section (2.2%; OR 0.47; 95% CI 0.27-0.82). Neonatal death was not associated with actual delivery mode. In TB, morbidity following combined delivery (19.8%) was higher than after vaginal delivery (9.5%; OR 0.55; 95% CI 0.41-0.74) or caesarean section (9.8%; OR 0.47; 95% CI 0.43-0.53). When outcomes were stratified for both presentation and delivery mode, mortality rate was lower after vaginal delivery than caesarean section for both vertex and nonvertex TB. AUTHOR'S CONCLUSION: An attempt at vaginal delivery should be considered in twin pregnancies with vertex/vertex presentation.

Prenatal exposure to hyperemesis gravidarum linked to increased risk of psychological and behavioral disorders in adulthood.

Hyperemesis gravidarum (HG), severe nausea and vomiting of pregnancy, is characterized by long-term maternal stress, undernutrition and dehydration. While maternal stress and malnutrition of pregnancy are linked to poor neonatal outcome and associated with poor adult health, long-term outcome of fetal exposure to HG has never been explored. The purpose of this study is to determine whether long-term emotional and behavioral diagnoses may be associated with fetal exposure to HG. Emotional and behavioral diagnoses of adults born of a pregnancy complicated by HG were compared to diagnoses from non-exposed controls. Offspring exposed to HG in utero were significantly more likely to have a psychological and behavioral disorder (OR = 3.6, P < 0.0001) with diagnoses primarily of depression, bipolar disorder and anxiety. In utero exposure to HG may lead to increased risks of psychological and behavioral disorders in the offspring.

Tropical nematode diversity: vertical stratification of nematode communities in a Costa Rican humid lowland rainforest.

Comparisons of nematode communities among ecosystems have indicated that, unlike many organisms, nematode communities have less diversity in the tropics than in temperate ecosystems. There are, however, few studies of tropical nematode diversity on which to base conclusions of global patterns of diversity. This study reports an attempt to estimate nematode diversity in the lowland tropical rainforest of La Selva Biological Research Station in Costa Rica. We suggest one reason that previous estimates of tropical nematode diversity were low is because habitats above the mineral soil are seldom sampled. As much as 62% of the overall genetic diversity, measured by an 18S ribosomal barcode, existed in litter and understorey habitats and not in soil. A maximum-likelihood tree of barcodes from 360 individual nematodes indicated most major terrestrial nematode lineages were represented in the samples. Estimated 'species' richness ranged from 464 to 502 within the four 40 x 40 m plots. Directed sampling of insects and their associated nematodes produced a second set of barcodes that were not recovered by habitat sampling, yet may constitute a major class of tropical nematode diversity. While the generation of novel nematode barcodes proved relatively easy, their identity remains obscure due to deficiencies in existing taxonomic databases. Specimens of Criconematina, a monophyletic group of soil-dwelling plant-parasitic nematodes were examined in detail to assess the steps necessary for associating barcodes with nominal species. Our results highlight the difficulties associated with studying poorly understood organisms in an understudied ecosystem using a destructive (i.e. barcode) sampling method.

Sentinel nematodes of land-use change and restoration in tallgrass prairie.

Changes in land use and the associated changes in land cover are recognized as the most important component of human-induced global change. Much attention has been focused on deforestation, but grasslands are among the most endangered ecosystems on Earth. The North American tallgrass prairie is a dramatic example, exhibiting a greater than 95% decline in historical area. Renewed interest in prairie conservation and restoration has highlighted the need for ecological indicators of disturbance and recovery in native systems, including the belowground component. The tallgrass prairie differs from the agricultural systems that have replaced it in having greater diversity and heterogeneity of resources, less physical soil disturbance (although other disturbances, such as fire and grazing, are prominent), and greater nitrogen limitation. Understanding the responses of nematode taxa to these characteristic differences is crucial to the development and improvement of community indices, but while knowledge of disturbance responses by individual taxa is accumulating, the level of necessary taxonomic resolution remains in question. Although nematode communities generally are better described for temperate grasslands than for other natural ecosystems, identification of sentinel taxa is further confounded by high levels of diversity, and both spatial and temporal heterogeneity.

Incorporating Molecular Identification of Meloidogyne spp. into a Large-scale Regional Nematode Survey.

A regional nematode survey of potato fields was conducted in the central United States during 2002 and 2003. The survey encompassed seven states and included a morphological and molecular examination of nematodes of regulatory concern from 1,929 soil samples. No regulated pest species were recovered during this survey. Meloidogyne juveniles extracted from soil were identified by mitochondrial and 18S ribosomal molecular markers. Eighty-two DNA sequences representing the two marker regions for Meloidogyne species were submitted to GenBank to facilitate evaluation of marker variability. Sufficient 18S variation was observed among some Meloidogyne species to aid in identification; however, nucleotide sequence from this highly conserved region of 18S did not discriminate among M. arenaria, M. incognita, and M. javanica. The mitochondrial gene region provided greater species discrimination and revealed intraspecific variation among many isolates. One nucleotide substitution found in a subset of M. hapla isolates from west Texas and New Mexico affected a DraI restriction site used in the PCR/RFLP diagnostic protocol. None of the mitochondrial sequence variants observed in this study compromised the PCR/RFLP identification protocol for M. chitwoodi. Additional sequence analysis is recommended for validation and evaluation of genetic markers used in diagnostic decisions.

Morphological and Molecular Characterization of Meloidogyne mayaguensis Isolates from Florida.

The discovery of Meloidogyne mayaguensis is confirmed in Florida; this is the first report for the continental United States. Meloidogyne mayaguensis is a virulent species that can reproduce on host cultivars bred for nematode resistance. The perineal patterns of M. mayaguensis isolates from Florida show morphological variability and often are similar to M. incognita. Useful morphological characters for the separation of M. mayaguensis from M. incognita from Florida are the male stylet length values (smaller for M. mayaguensis than M. incognita) and J2 tail length values (greater for M. mayaguensis than M. incognita). Meloidogyne mayaguensis values for these characters overlap with those of M. arenaria and M. javanica from Florida. Enzyme analyses of Florida M. mayaguensis isolates show two major bands (VS1-S1 phenotype) of esterase activity, and one strong malate dehydrogenase band (Rm 1.4) plus two additional weak bands that migrated close together. Their detection requires larger amounts of homogenates from several females. Amplification of two separate regions of mitochondrial DNA resulted in products of a unique size. PCR primers embedded in the COII and 16S genes produced a product size of 705 bp, and amplification of the 63-bp repeat region resulted in a single product of 322 bp. Nucleotide sequence comparison of these mitochondrial products together with sequence from 18S rDNA and ITS1 from the nuclear genome were nearly identical with the corresponding regions from a M. mayaguensis isolate from Mayaguez, Puerto Rico, the type locality of the species. Meloidogyne mayaguensis reproduced on cotton, pepper, tobacco, and watermelon but not on peanut. Preliminary results indicate the M. mayaguensis isolates from Florida can reproduce on tomato containing the Mi gene. Molecular techniques for the identification of M. mayaguensis will be particularly useful in cases of M. mayaguensis populations mixed with M. arenaria, M. incognita, and M. javanica, which are the most economically important root-knot nematode species in Florida, and especially when low (<25) numbers of specimens of these species are recovered from the soil.

Vagus nerve stimulation: analysis of device parameters in 154 patients during the long-term XE5 study.

PURPOSE: To determine the effect of changes in device settings and duty cycle (on and off times) on the efficacy of vagus nerve stimulation (VNS) for refractory epilepsy. In the long-term XE5 study of VNS for intractable epilepsy, the median reduction in seizure frequency improved significantly after 1 year of follow-up. A central question is whether device changes improve efficacy. We analyzed the effects of device parameter changes on seizure frequency in 154 subjects who completed the study and who had complete data for analysis. METHODS: Retrospective analysis of device changes during the XE5 long-term study of VNS. During the XE5 long-term follow-up study, the subject's device settings were modified within a Food and Drug Administration (FDA)-approved range of output current, pulse duration, frequency, on time, and off time. Significant changes in device settings occurred after 3 months. We investigated the relationship between percentage reduction in seizures and changes in device parameters between the 3- and 12-month visits. Within-group comparisons were performed for those who continued on standard on/off cycle of 30 s on and 5 min off, and those with the most common off times of 3, 1.8, and < 1.1 min. RESULTS: Output current, pulse duration, frequency, and off time changed significantly between the 3- and 12-month long-term follow-ups. For the group as a whole, changes in device settings were not correlated with an improvement in efficacy. However, a significant improvement in efficacy occurred in a subgroup whose off time was reduced to < or = 1.1 min. In this group, the median reduction in seizures improved from 21% before the change in off time, to 39% after the change in off time (Wilcoxon Signed-Rank, p = 0.011). The responder rate (> 50% reduction in seizures) also significantly improved from 19 to 35% (McNemar's test, p = 0.046). CONCLUSIONS: The data from this retrospective analysis indicate that device changes were not the primary determinant of increased efficacy at 12 months of long-term follow-up. In general, patients who remained on the original settings of 30 s on and 5 min off continued to respond or improve in their response over the 1-year period. However, some patients may benefit from reductions in off time (increases in duty cycle). In a subgroup initially resistant to VNS, a change in off time to < or = 1.1 min off did result in significant improvements in efficacy.

First Report of Columbia Root Knot Nematode (Meloidogyne chitwoodi) in Potato in Texas.

Columbia root-knot nematode, Meloidogyne chitwoodi Golden et al. (1) was identified from potatoes, Solanum tuberosum L., collected from Dallam County, Texas in October 2000. Seed potatoes are the most likely source for this introduction. This nematode is currently found infecting potatoes grown in California, Colorado, Idaho, New Mexico, Nevada, Oregon, Utah, and Washington. Some countries prohibit import of both seed and table stock potatoes originating in states known to harbor M. chitwoodi. Lesions on the potatoes had discrete brown coloration with white central spots in the outer 1 cm of the tuber flesh. Female nematode densities averaged 3 per square centimeter of a potato section beneath the lesions. Nematodes were morphologically identified as M. chitwoodi based on the perineal pattern of mature females and the tail shape of juveniles per Golden et al. (1). Using polymerase chain reaction-RFLP of the rDNA ITS1 region and the mtDNA COII-16S rRNA region (2), individual juveniles were identified as M. chitwoodi based on their restriction fragment patterns. This is the first report of Columbia root-knot nematode infecting potatoes in Texas. The distribution of this nematode in potato fields throughout central United States should be determined. References: (1) A. N. Golden et al. J. Nematol. 12:319, 1980. (2) T. O. Powers and T. S. Harris. J. Nematol. 25:1, 1993.

Identification of Seed Gall Nematodes of Agronomic and Regulatory Concern with PCR-RFLP of ITS1.

A molecular analysis of eight described species of seed gall nematode, along with six undescribed isolates from different hosts, has revealed a strong association between nucleotide sequence polymorphism and host status. Each anguinid nematode associated with a unique host produced a unique PCR-RFLP pattern for the ITS1 region. Anguina species that had been synonymized in the past, Anguina agrostis, A. funesta, and A. wevelli (Afrina wevelli), were readily discriminated. Two undescribed species from northern New South Wales and southeastern South Australia, reported to be vectors of Rathyaibacter toxicus in the disease called ''floodplain staggers,'' were differentiated by a single restriction enzyme, and both could be separated easily from A. funesta, the vector of R. toxicus in annual ryegrass toxicity. Other species differentiated in this study include A. agropyronifloris, A. graminis, A. microlaenae, A. pacificae, and undescribed species from host species Dactylis glomerata, Agrostis avenacea, Polypogon monospeliensis, Stipa sp., Astrebla pectinata, and Holcus lanatus. Phylogenetic analysis of the ITS1 region suggests that considerable anguinid genetic diversification has accompanied specialization on different host species.

Increasing the impact of health plan report cards by addressing consumers' concerns.

Most plan report cards that compare the performance of health plans have framed the decision about plan choice as an opportunity to get better-quality care. This study uses a controlled experimental design to examine the effect of reframing the health plan choice decision to one that emphasizes protecting oneself from possible risk. The findings show that framing the health plan decision using a risk message has a consistent and significant positive impact on how consumers comprehend, value, and weight comparative performance information.

Applying cognitive design principles to formatting HRQOL instruments.

Researchers developing or using health-related quality of life (HRQOL) instruments can benefit from knowledge of state-of-the-art formatting methods for self-administered questionnaires. Three objectives in formatting design are: (1) to reduce errors in respondent navigation through the questionnaire that lead to item non-response and question misinterpretation; (2) to reduce respondent and administrative burden; and (3) to enhance respondent motivation in question answering and compliance with the request to participate. Based on an extensive literature review to identify techniques that have been shown to meet these objectives, we developed specific guidelines for HRQOL instruments concerning all aspects of questionnaire formatting. These guidelines represent well-motivated recommendations for improving HRQOL instruments, although their overall impact has not been empirically tested. We applied the guidelines to several HRQOL instruments that are widely used internationally, and obtained approval from the developers for all formatting changes to their instruments. Applying cognitive design principles and empirically substantiated formatting techniques produces an HRQOL instrument formatting with six critical attributes: simple, consistent, organized, natural, clear and attractive. The present paper contributes to the emerging research literature on the cognitive processes by which respondents answer HRQOL questions and demonstrates how 'cognitive aspects of survey methodology' research can improve HRQOL data collection efforts.

Assessing nuclear and mitochondrial DNA sequence variation within steinernema (rhabditida: steinernematidae).

DNA sequence analysis was used to characterize the nuclear ribosomal DNA ITS1 region and a portion of the COII and 16S rDNA genes of the mitochondrial genome from Steinernema entomopathogenic nematodes. Nuclear ITS1 nucleotide divergence among seven Steinernema spp. ranged from 6 to 22%, and mtDNA divergence among five species ranged from 12 to 20%. No intraspecific variation was observed among three S. feltiae strains. Phylogenetic analysis of both nuclear and mitochondrial DNA sequences confirms the existing morphological relationships of several Steinernema species. Both the rDNA ITS1 and mtDNA sequences were useful for resolving relationships among Steinernema taxa.

Early clinical results of the use of radiofrequency lesioning in the treatment of plantar fasciitis.

In this paper the authors discuss plantar fascial heel pain, including its etiology and treatment. The results of a retrospective study using radiofrequency lesioning on plantar fascial heel pain are presented and discussed. Thirty-nine patients were treated with radiofrequency lesioning, and 92% of the patients experienced complete resolution of symptoms following the procedure.