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PubMed2005

Examination of sex as an independent risk factor for adverse events after carotid endarterectomy.

BACKGROUND: The incidence of adverse events after carotid endarterectomy (CEA) for women compared with men is controversial. This report compares the incidence of perioperative stroke and death in men and women by examining the effect of comorbidities and hospital setting on CEA outcomes. METHODS: All CEAs performed in non-Federal acute-care Virginia hospitals between 1997 and 2001 were reviewed. Patient demographics, comorbidities, and hospital characteristics were compared for possible relationships to perioperative adverse events. RESULTS: A total of 14,095 CEAs were performed in 34 urban and 28 rural hospitals (9 high-volume and 53 low-volume hospitals); 42% were performed on women, and 58% were performed on men. Women experienced a significantly higher stroke rate (1.23%) than men (0.87%; P = .04) with bivariate analysis. However, logistic regression analysis of comorbidities and hospital settings demonstrated that sex was actually not independently related to adverse outcomes in CEA ( P = .08). Preoperative neurologic symptoms could not be evaluated as risk factors for adverse events. Acute coronary ischemia, history of arrhythmia, end-stage renal disease, nonwhite race, advanced age, and low hospital volume were all significantly related to mortality. History of arrhythmia was the only factor that was significantly related to the incidence of stroke. CONCLUSIONS: Logistic regression analysis of comorbidities and hospital setting indicated that female sex is not independently associated with higher mortality or a higher stroke rate during CEA. These data indicate that patients with carotid stenosis frequently have multiple medical problems that need to be carefully examined and controlled before any single patient or hospital factor is designated as significantly related to adverse outcomes.

Carotid Stenosis↗
PubMed2006

Skin cholesterol: test performance, evaluation of potential determinants and correlation analysis with cardiovascular risk factors and circulating markers of inflammation.

BACKGROUND: Skin cholesterol (SkC) has been suggested to be an additional risk predictor, so we evaluated the test performance, potential determinants of this marker as well as a potential correlation of SkC with markers of inflammation and the history of cardiovascular events. PATIENTS AND METHODS: SkC, determined by the non-invasive PREVU POC Skin Sterol test, as well as serum lipids, the body fat status, high-sensitive CRP (hs-CRP) and serum amyloid A (SAA) were evaluated in consecutive patients with and without documented atherosclerotic disease. RESULTS: SkC was assessed in 201 patients. The within-day precision (CV) was 3.8%, the day-to-day CV of the right hand was 8.6% and 4.3% for the left hand, respectively. Neither univariate analysis nor multiple regressions identified a significant influence of age, sex, serum lipids, body fat status, smoking or diabetes mellitus on SkC, corresponding results were observed in a further analysis including 174 of these patients concerning hs-CRP and SAA (all p > 0.05). T-test analyses detected no significant differences between patients with and without a history of coronary, peripheral vascular and cerebrovascular events (all p > 0.05). CONCLUSIONS: The PREVU POC Skin Sterol test for the assessment of SkC proved an acceptable test performance. SkC is independent from serum lipids, traditional cardiovascular risk factors, two sensitive markers of systemic inflammation as well as the history of cardiovascular events indicating that the perception of this parameter as an established marker of vascular disease is premature.

Aged↗
PubMed1990

The association between head trauma and Alzheimer's disease.

The relation between head trauma and Alzheimer's disease was one of four major risk factors explored in a case-control study of 130 matched pairs; cases were clinically diagnosed between January 1980 and June 1985 at two geriatric psychiatric clinics in Seattle, Washington, and controls were friends or nonblood relatives of the cases. Subjects were matched by age, sex, and relationship between the case and his or her surrogate respondent. Head injuries which resulted in a loss of consciousness or which caused the subject to seek medical care were documented by means of interviews with surrogate respondents. A history of head injury was recorded for 24% of the cases and 8.5% of the controls, yielding an odds ratio of 3.5 (95% confidence interval 1.5-8.3) in conditional logistic regression analysis adjusted for age at onset of disease symptoms and family history of Alzheimer's disease. The estimated risk of Alzheimer's disease increased as the time between the last head trauma event and the onset of disease symptoms diminished (p = 0.002). This trend remained statistically significant (p = 0.006) when head injuries which occurred within 5 years of onset of the disease were excluded from the analysis. There was some difference between cases and controls for the average duration of unconsciousness in events accompanied by such a loss, but this was not statistically significant. The two groups were also similar in the circumstances surrounding the injuries and in the frequency of alcohol problems. This is the third case-control study to find a statistically significant association between head trauma and Alzheimer's disease.

Aged↗
PubMed2006

Screening for inherited thrombophilia might be warranted among Eastern Mediterranean sickle-beta-0 thalassemia patients.

BACKGROUND: The role of genetic thrombophilia in the development of both micro and macro vascular complications in patients with hemoglobinopathies (Sickle cell disease and thalassemia) have been investigated with some studies negating its role while others suggesting it. Lebanon is known to harbor sickle cell disease, thalassemia and sickle beta-thalassemia hemoglobinopathy patients along with a documented high prevalence of genetic thrombophilia mutations. METHODS: Twelve sickle beta-0-thalassemia patients with no pervious history of thrombotic events were selected. These patients underwent a physical examination with history, echo Doppler, along with blood withdrawal for complete blood count and PCR analysis of a sample of DNA for Factor V Leiden G1691A, Factor II G20210A, and MTHFR C677T. Results were compared to a historical control of 50 Lebanese controls and 50 LebaneseThalassemia Intermedia (TI) patients. RESULTS: The results showed that 42%, 59%, and 8% of patients carried heterozygous Factor V Leiden, abnormal (homozygous & heterozygous) MTHFR, and heterozygous Factor II mutations respectively. The sickle-thalassemia patients were 5.24 and 4.39 times more likely to have Factor V Leiden as compared to the normal controls and TI patients respectively (p < 0.05). DISCUSSION: The increased prevalence of more than one prothrombotic genetic mutation among the group indicates a probable clustering phenomenon, unknown to us to which the high consanguinity rate (77%) may have contributed. The role of the specific MTHFR and Factor V Leiden double heterozygous combination in incidence, recurrence, and guidance of duration of therapy in VTE is not well defined in the literature despite the recognized higher risk of thrombosis among this patient population. Our findings suggest that genetic thrombophilia workup is necessary in patients with sickle-beta zero thalassemia presenting with thrombotic events and studies that include a larger number of patients are necessary in order to define specific guidelines.

Adolescent↗
PubMed2005

Partial sequence analysis of an atypical Turkish isolate provides further information on the evolutionary history of Plum pox virus (PPV).

A variety of techniques, such as typing with subgroup-specific monoclonal antibodies, restriction length polymorphism (RFLP) analysis or subgroup-specific RT-PCR are available for the discrimination of Plum pox virus (PPV) isolates. However, the existence of PPV isolates showing abnormal typing properties has been observed in the past [Candresse, T., Cambra, M., Dallot, S., Lanneau, M., Asensio, M., Gorris, M.T., Revers, F., Macquaire, G., Olmos, A., Boscia, D., Quiot J.B., Dunez, J., 1998. Comparison of monoclonal antibodies and polymerase chain reaction assays for the typing of isolates belonging to the D and M serotypes of Plum pox potyvirus. Phytopathology 88, 198-204.]. In an effort to understand the molecular mechanisms underlying such anomalous serological and molecular typing characteristics, partial 3' (1449 nt) and 5' (3706 nt) sequences have been determined for an atypical Turkish PPV isolate (Abricotier Turquie or Ab-Tk). The results obtained indicate that its unusual typing behaviour is caused by point mutations affecting key restriction sites and epitopes and confirm that this isolate represents a divergent member of the PPV-M subgroup. In addition, analysis of the partial Ab-Tk genomic sequences demonstrated that the 5' region of the genome of this isolate has a mosaic structure resulting from recombination event(s), shedding new light on the evolutionary history of Plum pox virus.

Antibodies, Monoclonal↗
PubMed1995

Separating population structure from population history: a cladistic analysis of the geographical distribution of mitochondrial DNA haplotypes in the tiger salamander, Ambystoma tigrinum.

Nonrandom associations of alleles or haplotypes with geographical location can arise from restricted gene flow, historical events (fragmentation, range expansion, colonization), or any mixture of these factors. In this paper, we show how a nested cladistic analysis of geographical distances can be used to test the null hypothesis of no geographical association of haplotypes, test the hypothesis that significant associations are due to restricted gene flow, and identify patterns of significant association that are due to historical events. In this last case, criteria are given to discriminate among contiguous range expansion, long-distance colonization, and population fragmentation. The ability to make these discriminations depends critically upon an adequate geographical sampling design. These points are illustrated with a worked example: mitochondrial DNA haplotypes in the salamander Ambystoma tigrinum. For this example, prior information exists about restricted gene flow and likely historical events, and the nested cladistic analyses were completely concordant with this prior information. This concordance establishes the plausibility of this nested cladistic approach, but much future work will be necessary to demonstrate robustness and to explore the power and accuracy of this procedure.

Ambystoma↗
PubMed1996

Hypertriglyceridemia and elevated lipoprotein(a) are risk factors for major coronary events in middle-aged men.

Cardiovascular risk factors were analyzed in 4,849 male participants, aged 40 to 65 years, in an 8-year follow-up of the Münster Heart Study (Prospective Cardiovascular Münster Study; PROCAM). One hundred eighty-one definite nonfatal myocardial infarctions, 49 fatal myocardial infarctions, and 28 sudden cardiac deaths were observed. Multiple logistic function analysis confirmed that age, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, systolic blood pressure, cigarette smoking, diabetes mellitus, angina pectoris, and family history of myocardial infarction were important cardiovascular risk factors. Interestingly, this analysis revealed a significant and independent association between serum levels of triglycerides and the incidence of major coronary events. The relation between lipoprotein(a) [Lp(a)] levels and the occurrence of major coronary events was analyzed in a subgroup of 878 men. Thirty-three probands with major coronary events had significantly higher geometric mean levels of Lp(a) than 828 men who did not experience major coronary events (0.09 vs 0.05 g/L; p <0.011). Thus, in addition to established risk for factors, serum levels of triglycerides and Lp(a) are sensitive indicators of increased risk major coronary events.

Adult↗
PubMed2005

Haplotype trees and modern human origins.

A haplotype is a multisite haploid genotype at two or more polymorphic sites on the same chromosome in a defined DNA region. An evolutionary tree of the haplotypes can be estimated if the DNA region had little to no recombination. Haplotype trees can be used to reconstruct past human gene-flow patterns and historical events, but any single tree captures only a small portion of evolutionary history, and is subject to error. A fuller view of human evolution requires multiple DNA regions, and errors can be minimized by cross-validating inferences across loci. An analysis of 25 DNA regions reveals an out-of-Africa expansion event at 1.9 million years ago. Gene flow with isolation by distance was established between African and Eurasian populations by about 1.5 million years ago, with no detectable interruptions since. A second out-of-Africa expansion occurred about 700,000 years ago, and involved interbreeding with at least some Eurasian populations. A third out-of-Africa event occurred around 100,000 years ago, and was also characterized by interbreeding, with the hypothesis of a total Eurasian replacement strongly rejected (P < 10(-17)). This does not preclude the possibility that some Eurasian populations could have been replaced, and the status of Neanderthals is indecisive. Demographic inferences from haplotype trees have been inconsistent, so few definitive conclusions can be made at this time. Haplotype trees from human parasites offer additional insights into human evolution and raise the possibility of an Asian isolate of humanity, but once again not in a definitive fashion. Haplotype trees can also indicate which genes were subject to positive selection in the lineage leading to modern humans. Genetics provides many insights into human evolution, but those insights need to be integrated with fossil and archaeological data to yield a fuller picture of the origin of modern humans.

Emigration and Immigration↗
PubMed2006

Characterization of impulsivity in suicide completers: clinical, behavioral and psychosocial dimensions.

BACKGROUND: Impulsivity is a personality trait thought to be linked to suicide. Yet, not all suicides are highly impulsive. We aimed to better understand clinical, behavioral and psychosocial correlates of the association between suicide and impulsive behavior. METHODS: One hundred sixty four suicide cases with impulsivity scores based on the Barratt Impulsivity Scale (BIS) were investigated. To examine the most extreme phenotypes, one hundred suicide cases, representing subjects with BIS scores above the 70th percentile and below the 30th percentile, were compared on clinical, behavioral and psychosocial suicide risk factors assessed by way of structured psychological autopsy methods with best informants. RESULTS: The impulsive suicide cases were significantly younger, exhibited higher measures of aggressive behavior, and were more likely to have a cluster B diagnosis as well as lifetime and 6-month prevalence of alcohol and drug abuse/dependence. They also differed significantly from their non-impulsive counterparts on all subscales of the TCI except for Harm Avoidance and Reward Dependence. Impulsive suicide completers were more likely to have had a history of childhood abuse and to have experienced a triggering life event up to a week preceding their death. A multivariate analysis indicated that 6-month prevalence of substance abuse/dependence and high aggressive behavior remained significant even after controlling for other significant variables. LIMITATIONS: This study was carried out using proxy-based interviews. CONCLUSIONS: Most of the known clinical and behavioral risk factors commonly associated with suicide are particularly valid for impulsive suicide completers. Further, triggering and adverse life events seem to play a role primarily in impulsive suicide.

Adult↗
PubMed1993

Home event recordings of oxygenation, breathing movements, and heart rate and rhythm in infants with recurrent life-threatening events.

For an evaluation of the usefulness of event recording in identifying mechanisms for apparent life-threatening events, 94 infants (median age, 3.1 months; range, 0.5 to 12 months) with a history of two or more apparent life-threatening events of hitherto unknown cause underwent event recording of transcutaneous oxygen pressure, arterial oxygen saturation, (not recorded in all patients), breathing movements, pulse waveforms, electrocardiogram, and instantaneous heart rate. Recordings were triggered by a fall in transcutaneous oxygen pressure to less than 20 mm Hg. During a median duration of event recording of 1.3 months (0.1 to 10 months), 52 events were recorded in 34 patients; 7 of the events had to be excluded because of uninterpretable signals. The following mechanisms were identified in the remaining 30 patients (45 events): a sudden change in skin perfusion but without hypoxemia (6 in 5 patients), hypoxemia induced by an epileptic seizure (6 in 5 patients), hypoxemia induced by suffocation by a parent (4 in 4 patients), and parental fabrication of events and medical history (7 in 6 patients). In the remaining 22 events in 12 patients, the precise mechanism of events could not be identified. Analysis of these as-yet-unexplained events showed prolonged abnormal hypoxemia (a fall in transcutaneous oxygen pressure to between 4 and 18 mm Hg and a fall in arterial oxygen saturation to 5% to 75%), lasting for 40 to 500 seconds in all. Only five of these events involved prolonged (> 20 seconds) apneic pauses, and only four an episode of bradycardia (heart rate < 80 or 60 beats/min). Thus event recording identified various mechanisms of apparent life-threatening events. In the events that remained unexplained, prolonged apneic pauses or episodes of bradycardia were found in only a minority. The identification of hypoxemia therefore may be more relevant to the early detection of these events than the identification of apnea or bradycardia or both. The relevance of these findings with regard to sudden infant death syndrome remains to be determined.

Apnea↗
PubMed1996

Preliminary results of a randomized trial comparing neoadjuvant chemotherapy (cisplatin, epirubicin, bleomycin) plus radiotherapy vs. radiotherapy alone in stage IV(> or = N2, M0) undifferentiated nasopharyngeal carcinoma: a positive effect on progression-free survival.

PURPOSE: Our Phase II trial using bleomycin, epirubicin, and cisplatin (BEC) protocol in the treatment of loco-regionally advanced undifferentiated nasopharyngeal carcinoma (UCNT) patients has shown encouraging results with high objective response, disease-free survival, and overall survival rates. To establish the value of this BEC regimen as neoadjuvant chemotherapy, we initiated in 1989 a large international Phase III trial. It compares three cycles of BEC followed by radiotherapy to radiotherapy alone. METHODS AND MATERIALS: From November 1989 to October 1993, 339 patients with negative metastases workup, stratified by accrual center have been randomized, 168 to radiotherapy alone and 171 to chemotherapy plus radiotherapy. All patients characteristics were well balanced in both arms. There was a quality control/data verification by specialist panel (radiology, histology, radiotherapy, chemotherapy) and external policy board expert every 60-80 patients having completed treatment. RESULTS: With a median follow-up of 49 months (range: 23-70), despite an excess of treatment-related deaths in the neoadjuvant chemotherapy arm (8 vs. 1%), there is a significant difference in disease free survival favoring the chemotherapy arm (p < 0.01). The proportion of local and/or regional metastases was comparable in both arms. No difference in overall survival is seen but the numbers of events needed for analysis has not yet been reached. CONCLUSIONS: BEC type neoadjuvant chemotherapy has a significant impact in the natural history of UCNT. Further follow-up is needed to establish an eventual overall survival difference.

Adult↗
PubMed2001

Chromosomal instability in chromosome band 12p13: multiple breaks leading to complex rearrangements including cytogenetically undetectable sub-clones.

During fluorescence in situ hybridization (FISH) analysis of metaphase cells from 70 patients with lymphoid and myeloid hematologic malignancies and chromosomal rearrangements involving band 12p13, we identified nine patients (four with lymphoid malignancies, four with myeloid malignancies and one with biphenotypic leukemia) who showed more complicated rearrangements than we had expected from conventional cytogenetic study. In six patients, multiple breaks occurred in small segments of 12p with subsequent translocations and insertions of these segments into other chromosomes, sometimes to unexpected regions. In three patients additional chromosome breaks resulted in a sub-clone which was cytogenetically indistinguishable from the main clone in each patient based on the cytogenetic analysis. These subtle molecular events were detected exclusively in a region covering TEL/ETV6 and KIP1/CDKN1B. Seven of nine had a previous history of chemo/radiotherapy; all the patients showed complex karyotypes, even though they were newly diagnosed with leukemia. Survival data were available in five patients, and all survived less than 6 months. These findings suggest that the 12p13 region, especially the above-mentioned region, is genetically unstable and fragile. It is likely that multiple chromosome breaks were induced through mutagens used in chemo/ radiotherapy, and are associated with a sub-group of patients with an extremely bad prognosis.

Chromosome Fragility↗
PubMed1999

Amniotic fluid volume and onset of labor in physiological pregnancy.

We measure, by means of ultrasound, the amniotic fluid volume (expressed as maximal vertical pocket or MVP) in 646 normal pregnancies at the 39th gestational week. Our aim is to evaluate the possible correlation between MVP and onset of the labor. In a 2-week follow-up, the onset of the labor is considered the "event" variable in a time-dependent statistical analysis. Univariate analysis (Kaplan-Meier algorithm) describes a different trend in predicting the onset of labor when a stratification of MVP < 50 and > or = 50 mm was performed (chi2 = 7.91 p < 0.0049 with 1 df, Breslow-Gehan test). The first category was comprised of 496 fetuses with a median (min-max) MVP of 39 mm (25-49), the second category of 150 fetuses with a MVP of 57 mm (50-100). The results suggest that lower levels of MVP are associated to a higher percentage of the onset of labor. Furthermore, in our measurement, performed at the 39th gestational week, the correlation with the events is higher within the 40th gestational week. In fact, at 7 days from the amniotic fluid measurement, the onset of labor and the subsequent delivery is observed in 80.65 and 73.00% of the cases when they are stratified according to MVP < 50 and > or = 50 mm. At the end of the follow-up, instead, the percentage of "events" is similar, 88.10 and 86.67%, respectively. Adjustment for covariates (Cox analysis), as well as maternal age, neonatal weight, and obstetrics history, show an odds ratio (95% C.I.) of 2.08 (1.61-2.69) for MVP, using the above cutoff level. In physiological pregnancy, lower levels of amniotic fluid at term correlated to a higher probability of the onset of labor.

Adolescent↗
PubMed2005

Recurrent event analysis of lapse and recovery in a smoking cessation clinical trial using bupropion.

We report a reanalysis of data from a prior study describing the event history of quitting smoking aided by bupropion, using recurrent-event models to determine the effect of the drug on occurrence of lapses and recoveries from lapse (resumption of abstinence). Data were collected on 1,070 subjects across two similar double-blind randomized clinical trials of bupropion versus placebo and fitted with separate Cox regression models for lapse and recovery. Analyses were split using discrete time-varying covariates between the treatment (weeks 1-10) and follow-up phases (end of treatment to 12 months). Bupropion was associated with slower lapse during treatment for both sexes, and being female was associated with faster lapse across both phases. Drug did not affect time to recovery for males but was associated with faster recovery among females, allowing women to recover as quickly as men. High levels of nicotine dependence did not affect time to lapse but were associated with slower recovery from lapse across treatment and follow-up phases. During the treatment phase, higher levels of baseline depression symptoms had no effect on time to lapse but were associated with slower recovery from lapse. Results highlight the asymmetry in factors preventing lapse versus promoting recovery. Specifically, dependence, depression symptoms, and a sex x drug interaction were found to affect recovery but not lapse. Further research disentangling lapse and recovery events from summary abstinence measures is needed to help us develop interventions that take advantage of bupropion at its best and that compensate where it is weak.

Adult↗
PubMed2003

The J-shaped effect of coffee consumption on the risk of developing acute coronary syndromes: the CARDIO2000 case-control study.

The effect of coffee consumption on cardiovascular disease has been debated for many years. In this work, we evaluated the association between coffee consumption and the risk of developing acute coronary syndromes, based on a random sample of 848 patients with their first coronary heart disease event and 1078 frequency-matched controls with no cardiovascular disease in their medical history, from the entire country. The multivariate analysis raises a J-shaped association between the risk of developing acute coronary syndromes and the quantity of coffee consumed per day. In particular, the odds ratios for moderate (<300 mL/d), heavy (300-600 mL/d), and very heavy (>600 mL/d), consumption, relative to no consumption, were 0.69 (95% CI, 0.50-0.86), 1.56 (95% CI, 1.10-2.34) and 3.10 (95% CI, 1.82-5.26), respectively, after controlling for the presence of hypertension, hypercholesterolemia, diabetes mellitus, family history of premature coronary heart disease, physical activity status, smoking habits, BMI, alcohol consumption, triglycerides, consumption of several food items, depression scale score and education status. The suggested J-shaped association between coffee consumption and the risk of developing acute coronary syndromes may partially explain the conflicting results from other studies in the past.

Aged↗
PubMed2002

Prognostic factors in high-grade osteosarcoma of the extremities or trunk: an analysis of 1,702 patients treated on neoadjuvant cooperative osteosarcoma study group protocols.

PURPOSE: To define prognostic factors for response and long-term outcome for a wide spectrum of osteosarcomas, extending well beyond those of the typical young patient with seemingly localized extremity disease. PATIENTS AND METHODS: A total of 1,702 consecutive newly diagnosed patients with high-grade osteosarcoma of the trunk or limbs registered into the neoadjuvant studies of the Cooperative Osteosarcoma Study Group before July 1998 were entered into an analysis of demographic, tumor-related, and treatment-related variables, response, and survival. The intended therapeutic strategy included preoperative and postoperative chemotherapy with multiple agents as well as surgery of all operable lesions. RESULTS: Axial tumor site, male sex, and a long history of symptoms were associated with poor response to chemotherapy in univariate and multivariate analysis. Actuarial 10-year overall and event-free survival rates were 59.8% and 48.9%. Among the variables assessable at diagnosis, patient age (actuarial 10-year survival > or = 40, 41.6%; < 40, 60.2%; P =.012), tumor site (axial, 29.2%; limb, 61.7%; P <.0001), and primary metastases (yes, 26.7%; no, 64.4%; P <.0001), and for extremity osteosarcomas, also size (> or = one third, 52.5%; < one third, 66.7%; P <.0001) and location within the limb (proximal, 49.3%; other, 63.9%; P <.0001), had significant influence on outcome. Two additional important prognostic factors were treatment related: response to chemotherapy (poor, 47.2%; good, 73.4%; P <.0001) and the extent of surgery (incomplete, 14.6%; macroscopically complete, 64.8%; P <.0001). All factors except age maintained their significance in multivariate testing, with surgical remission and histologic response emerging as the key prognostic factors. CONCLUSION: Tumor site and size, primary metastases, response to chemotherapy, and surgical remission are of independent prognostic value in osteosarcoma.

Adolescent↗
PubMed2025

Bayesian Inference of Pathogen Phylogeography using the Structured Coalescent Model.

Over the past decade, pathogen genome sequencing has become well established as a powerful approach to study infectious disease epidemiology. In particular, when multiple genomes are available from several geographical locations, comparing them is informative about the relative size of the local pathogen populations as well as past migration rates and events between locations. The structured coalescent model has a long history of being used as the underlying process for such phylogeographic analysis. However, the computational cost of using this model does not scale well to the large number of genomes frequently analysed in pathogen genomic epidemiology studies. Several approximations of the structured coalescent model have been proposed, but their effects are difficult to predict. Here we show how the exact structured coalescent model can be used to analyse a precomputed dated phylogeny, in order to perform Bayesian inference on the past migration history, the effective population sizes in each location, and the directed migration rates from any location to another. We describe an efficient reversible jump Markov Chain Monte Carlo scheme which is implemented in a new R package StructCoalescent. We use simulations to demonstrate the scalability and correctness of our method and to compare it with existing software. We also applied our new method to several state-of-the-art datasets on the population structure of real pathogens to showcase the relevance of our method to current data scales and research questions.

Bayes Theorem↗
PubMedDate not supplied

Declining beta-HCG levels: an indicator for expectant approach in ectopic pregnancy.

Early surgical intervention in ectopic pregnancy is desirable. However, occasionally some patients do not benefit from this approach, as the natural history of ectopic pregnancy is not always tubal rupture or any other catastrophic event. A retrospective as well as a prospective analysis of 144 cases of suspected ectopic pregnancies was performed. The results of this study support expectant management in cases where serum beta-HCG levels are declining, provided the patient is stable and has no acute abdominal symptoms.

Chorionic Gonadotropin↗