Generalized additive models to analyze nonlinear trends in biomedical longitudinal data using R: Beyond repeated measures ANOVA and linear mixed models.

In biomedical research, the outcome of longitudinal studies has been traditionally analyzed using the repeated measures analysis of variance (rm-ANOVA) or more recently, linear mixed models (LMEMs). Although LMEMs are less restrictive than rm-ANOVA as they can work with unbalanced data and non-constant correlation between observations, both methodologies assume a linear trend in the measured response. It is common in biomedical research that the true trend response is nonlinear and in these cases the linearity assumption of rm-ANOVA and LMEMs can lead to biased estimates and unreliable inference. In contrast, GAMs relax the linearity assumption of rm-ANOVA and LMEMs and allow the data to determine the fit of the model while also permitting incomplete observations and different correlation structures. Therefore, GAMs present an excellent choice to analyze longitudinal data with non-linear trends in the context of biomedical research. This paper summarizes the limitations of rm-ANOVA and LMEMs and uses simulated data to visually show how both methods produce biased estimates when used on data with non-linear trends. We present the basic theory of GAMs and using reported trends of oxygen saturation in tumors, we simulate example longitudinal data (2 treatment groups, 10 subjects per group, 5 repeated measures for each group) to demonstrate their implementation in R. We also show that GAMs are able to produce estimates with non-linear trends even when incomplete observations exist (with 40% of the simulated observations missing). To make this work reproducible, the code and data used in this paper are available at: https://github.com/aimundo/GAMs-biomedical-research.

THE FIRST REPORT OF A CROTALID ENVENOMATION IN A DOMESTICATED FERRET ( MUSTELA FURO) AND SUCCESSFUL TREATMENT WITH A NOVEL F(AB')2 ANTIVENOM.

A case report of a domesticated ferret ( Mustela furo) envenomated by a presumptive rattlesnake ( Crotalus sp.) treated successfully and safely with the novel Fab (2') North American Snake Antivenom (Veteria Labs). The ferret presented with clinical signs of depressed mentation and facial edema following a rattlesnake ( Crotalus sp.) bite. It developed hypotension, thrombocytopenia, and ecchymosis following the envenomation. It was treated with Fab (2') antivenom and given supportive care including crystalloid fluids and analgesia to resolution of clinical signs. This is the first documented case of rattlesnake envenomation in this species. This case supports the efficacy and short-term safety of this Fab (2') antivenom in this species without the use of antihistamines or glucocorticoids. This report also addresses the current standards of care with thorough review of the literature involving rattlesnake envenomation in zoological species.

Triple paternal contribution to a normal/complete molar chimeric singleton placenta.

A comprehensive study of unusual cases of placental pathology may provide insight into mechanisms of normal human fertilization and early embryonic development by examining the exception to the rule. A gravida three para two 39-year-old woman was monitored by ultrasound from 16 weeks of gestation for cystic placenta. A female newborn was born at 36 weeks gestation. Pathologic examination of the partially cystic placenta revealed a singleton placenta comprised of 2/3 normal placenta and 1/3 complete hydatidiform mole, largely degenerated. Immunostaining for p57 was negative in stromal cells of the molar villi. Chromogenic in-situ hybridization revealed diploidy in both normal and molar parts. A total of 16 microsatellites were studied by short tandem repeat analysis, 11 of which were informative. The analysis revealed bipaternal molar tissue of dispermic origin. The paternal monospermic contribution to the normal part was different from that in the molar part, thus resulting in tripaternal contribution to the conceptus. A chimera is a single organism composed of two or more different populations of genetically distinct cells that originated from different zygotes (tetragametic) whereas mosaic is a mixture of two cell lines in one organism originating from one zygote. The possible mechanisms leading to the formation of chimeric/mosaic placenta in our case (one of the components being complete hydatidiform mole), including twinning, fusion at an early embryonic stage and diploidization of triploids, are discussed.

Analysis of E2 gene integrity in HPV16 and HPV58 viruses isolated from women with cervical pathology.

Integration of human papillomavirus (HPV) DNA into human cells accompanied by the disruption of the viral genome has been described as a prerequisite for cancer development. This study aimed to investigate E2 gene integrity of HPV16 and HPV58 viruses isolated from infected women with cervical lesions. Forty-two HPV16- and 31 HPV58-positive samples were analysed. E2 integrity was assumed when all fragments covering the E2 gene were amplified with specific polymerase chain reaction primers. Overall, in 59% of the samples, at least one fragment was not amplified in HPV16- (57%) and HPV58-positive samples (61%). Samples from high-grade squamous intraepithelial lesions had the highest frequency of E2 gene disruptions (73%), followed by samples from low-grade squamous intraepithelial lesions (63%) and, finally, samples from invasive cervical cancer (35%). Association between the integrity status of the E2 gene, and lesion grade was assessed by the chi-squared test applied to the combined set of viruses (p = 0.6555) or to populations of the same virus type (HPV58, p = 0.3101; HPV16, p = 0.3024). In conclusion, in this study, no association was found between the presence of E2 gene disruptions and the grade of cervical lesions caused by HPV16 and HPV58.

[Anaerobiospirillum thomasii bacteremia with fatal outcome]. / Bacteriemia por Anaerobiospirillum thomasii con desenlace fatal.

Anaerobiospirillum thomasii has been reported as a causative agent of diarrhea in humans; however no bacteremia associated with this pathogen has been described so far. We present here the first case of fatal A. thomasii bacteremia in an alcoholic patient.

Brain-derived neurotrophic factor is expressed in rat and human placenta and its serum levels are similarly regulated throughout pregnancy in both species.

OBJECTIVE: Pregnancy is characterized by several metabolic changes that promote fat gain and later onset of insulin resistance. As Brain-derived neurotrophic factor (BDNF) decreases hyperglycaemia and hyperphagia, we aimed to investigate the potential role of placental and circulating BDNF levels in these pregnancy-related metabolic changes in rats and humans. DESIGN AND METHODS: We identified the mRNA and protein expression of placental BDNF and its receptor TrkB using real-time PCR, Western blot and immunohistochemical approaches in both rat and humans. Serum BDNF was measured by ELISA. We also did a longitudinal prospective cohort study in 42 pregnant women to assess BDNF levels and correlations with other metabolic parameters. RESULTS: We found that BDNF and TrkB are expressed in both rat and human placenta. In rat, both placental mRNA and serum levels are increased throughout pregnancy, whereas their protein levels are significantly decreased at the end of gestation. Serum BDNF levels in pregnant women are significantly lower in the first trimester when compared to the second and third trimester (P < 0·0148, P < 0·0012, respectively). Serum BDNF levels were negatively correlated with gestational age at birth and fasting glucose levels. CONCLUSION: Our findings suggest that both BDNF and its receptor TrkB are expressed in rodent and human placenta being regulated during pregnancy. Taken together, these findings support a role of BDNF in the regulation of several metabolic functions during pregnancy.

Prostaglandins for management of retained placenta.

BACKGROUND: Retained placenta affects 0.5% to 3% of women following delivery and it is a major cause of maternal death due to postpartum haemorrhage. Usually, retained placenta has been managed by manual removal or curettage under anaesthesia, which may be associated with haemorrhage, infection and uterine perforation. Medical management to facilitate the delivery of the retained placenta could be a safe alternative avoiding surgical intervention. OBJECTIVES: To assess the effectiveness and safety of prostaglandins for the management of retained placenta. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (1 December 2013), LILACS (1982 to 1 December 2013), SciELO (1998 to 1 December 2013), Web of Science (2001 to 1 December 2013), openSIGLE (1997 to 1 December 2013), World Health Organization International Clinical Trials Registry Platform (ICTRP) (1 December 2013) and the metaRegister of Controlled Trials (mRCT) (1 December 2013). We also contacted authors of included studies and reviewed the reference lists of retrieved studies. SELECTION CRITERIA: Randomised controlled clinical trials comparing the use of prostaglandins (or prostaglandin analogues) with placebo, expectant management, tocolytic drugs, any other prostaglandins or surgical interventions for the management of retained placenta after vaginal delivery of singleton live infants of 20 or more weeks of gestation. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trials for inclusion and assessed trial quality. Two review authors independently extracted data. Data were checked for accuracy. Any disagreements were resolved through consensus or consultation with a third review author when required. Authors of the included studies were contacted for additional information. MAIN RESULTS: We included three trials, involving 244 women. The studies were considered to be at high risk of bias.The prostaglandins used were PG E2 analogue (sulprostone) in 50 participants and PG E1 analogue (misoprostol) in 194 participants at a dose of 250 mcg and 800 mcg respectively. The prostaglandins compared with placebo, were not superior in reducing the rate of manual removal of placenta (average risk ratio (RR) 0.82; 95% confidence interval (CI) 0.54 to 1.27), severe postpartum haemorrhage (RR 0.80; 95% CI 0.55 to 1.15), need for blood transfusion (RR 0.72; 95% CI 0.43 to 1.22), mean blood loss (mean difference (MD) -205.26 mL; 95% CI -536.31 to 125.79, random-effects) and the mean time from injection to placental removal (MD -7.00 minutes; 95% CI -21.20 to 7.20). Side-effects were no different between groups (vomiting, headache, pain and nausea between injection and discharge from the labour ward), with the exception of shivering, which was more frequent in women receiving prostaglandins (RR 10.00; 95% CI 1.40 to 71.49). We did not obtain any data for the primary outcomes of maternal mortality and the need to add another therapeutic uterotonic. AUTHORS' CONCLUSIONS: Currently there is limited, very low-quality evidence relating to the effectiveness and the safety using prostaglandins for the management of retained placenta. Use of prostaglandins resulted in less need for manual removal of placenta, severe postpartum haemorrhage and blood transfusion but none of the differences reached statistical significance. Much larger, adequately powered studies are needed to confirm that these clinically important beneficial effects are not just chance findings.Similarly, no differences were detected between prostaglandins and placebo in mean blood loss or the mean time from injection to placental removal (minutes) or side-effects (vomiting, headache, pain and nausea between injection and discharge from the labour ward) except for 'shivering' which was more frequent in women who received prostaglandin. The included studies were of poor quality and there is little confidence in the effect estimates; the true effect is likely to be substantially different. We can not make any recommendations about changes to clinical practice. More high-quality research in this area is needed.

Imiquimod for anogenital warts in non-immunocompromised adults.

BACKGROUND: 30% of people with anogenital warts (AGW) have spontaneous regression of lesions but there is no way to determine whether a specific lesion will remain. There are a wide range of options available for treating people with AGW and selection is based on clinician's experience, patient preferences and adverse effects. The imiquimod could offer the advantages of patient-applied therapies without incurring the limitations of provider-administered treatments. OBJECTIVES: To assess the effectiveness and safety of imiquimod for the treatment of AGW in non-immunocompromised adults. SEARCH METHODS: We searched the Cochrane Sexually Transmitted Infections Group Specialized Register (15 April 2014), CENTRAL (1991 to 15 April 2014), MEDLINE (1946 to 15 April 2014), EMBASE (1947 to 15 April 2014), LILACS (1982 to 15 April 2014), World Health Organization International Clinical Trials Registry (ICTRP) (15 April 2014), ClinicalTrials.gov (15 April 2014), Web of Science (2001 to 15 April 2014) and OpenGrey (15 April 2014). We also handsearched conference proceedings, contacted trial authors and reviewed the reference lists of retrieved studies. SELECTION CRITERIA: Randomized controlled trials (RCTs) comparing the use of imiquimod with placebo, any other patient-applied or any other provider-administered treatment (excluding interferon and 5-fluorouracil which are assessed in other Cochrane Reviews) for the treatment of AGW in non-immunocompromised adults. DATA COLLECTION AND ANALYSIS: Three review authors independently assessed trials for inclusion, extracted data and assessed risk of bias. We resolved any disagreements through consensus. The quality of the evidence was assessed using the GRADE approach. MAIN RESULTS: Ten RCTs (1734 participants) met our inclusion criteria of which six were funded by industry. We judged the risk of bias of the included trials as high. Six trials (1294 participants) compared the use of imiquimod versus placebo. There was very low quality evidence that imiquimod was superior to placebo in achieving complete and partial regression (RR 4.03, 95% CI 2.03 to 7.99; RR 2.56, 95% CI 2.05 to 3.20, respectively). When compared with placebo, the effects of imiquimod on recurrence (RR 2.76, 95% CI 0.70 to 10.91), appearance of new warts (RR 0.76, 95% CI 0.58 to 1.00) and frequency of systemic adverse reactions (RR 0.91, 95% CI 0.63 to 1.32) were imprecise. We downgraded the quality of evidence to low or very low. There was low quality evidence that imiquimod led to more local adverse reactions (RR 1.73, 95% CI 1.18 to 2.53) and pain (RR 11.84, 95% CI 3.36 to 41.63).Two trials (105 participants) compared the use of imiquimod versus any other patient-applied treatment (podophyllotoxin and podophyllin). The estimated effects of imiquimod on complete regression (RR 1.09, 95% CI 0.80 to 1.48), partial regression (RR 0.77, 95% CI 0.40 to 1.47), recurrence (RR 0.49, 95% CI 0.21 to 1.11) or the presence of local adverse reactions (RR 1.24, 95% CI 1.00 to 1.54) were imprecise (very low quality evidence). There was low quality evidence that systemic adverse reactions were less frequent with imiquimod (RR 0.30, 95% CI 0.09 to 0.98).Finally, two trials (335 participants) compared imiquimod with any other provider-administered treatment (ablative methods and cryotherapy). There was very low quality of evidence that imiquimod did not have a lower frequency of complete regression (RR 0.84, 95% CI 0.56 to 1.28). There was very low quality evidence that imiquimod led to a lower rate of recurrence during six-month follow-up (RR 0.24, 95% CI 0.10 to 0.56) but this did not translate in to a lower recurrence from six to 12 months (RR 0.71, 95% CI 0.40 to 1.25; very low quality evidence). There was very low quality evidence that imiquimod was associated with less pain (RR 0.30, 95% CI 0.17 to 0.54) and fewer local reactions (RR 0.55, 95% CI 0.40 to 0.74). AUTHORS' CONCLUSIONS: The benefits and harms of imiquimod compared with placebo should be regarded with caution due to the risk of bias, imprecision and inconsistency for many of the outcomes we assessed in this Cochrane Review. The evidence for many of the outcomes that show imiquimod and patient-applied treatment (podophyllotoxin or podophyllin) confer similar benefits but fewer systematic reactions with the Imiquimod, is of low or very low quality. The quality of evidence for the outcomes assessing imiquimod and other provider-administered treatment were of very low quality.

The phylogenetic relationships of three new species of the Cyrtodactylus pulchellus complex (Squamata: Gekkonidae) from poorly explored regions in northeastern Peninsular Malaysia.

An integrative taxonomic analysis of three newly discovered populations of the gekkonid genus Cyrtodactylus Gray from Merapoh, Pahang; Gunung Stong, Kelantan; and Gunung Tebu, Terengganu indicate they are part of the C. pulchellus complex and each is a new species and thusly named Cyrtodactylus sharkari sp. nov., C. jelawangensis sp. nov., and C. timur sp. nov., respectively. Each species bears a unique suite of morphological and color pattern characters separating them from each other and all other nominal species in the C. pulchellus complex. Their phylogenetic relationships to each other and other species in the C. pulchellus complex were unexpected in that they are not in accordance with the general distribution of the species in this complex, underscoring the intricate historical biogeography of the Thai-Malay Peninsula. These descriptions highlight our current lack of knowledge concerning the herpetological diversity and distribution of species in northeastern Peninsular Malaysia.

Poly(dimethylsiloxane)-supported ionogels with a high ionic liquid loading.

The immiscibility of poly(dimethylsiloxane) (PDMS) and ionic liquids (ILs) was overcome to create PDMS-supported IL gels (ionogels) with IL loadings of up to 80% by mass through a simple sol-gel reaction at room temperature. By stirring a mixture of a functionalized PDMS oligomer, formic acid, and an IL (or lithium-in-IL solution), a resin was formed that could be cast to create a freestanding, flexible ionogel. PDMS-supported ionogels exhibited favorable ionic conductivity (ca. 3 mS cm(-1)) and excellent mechanical behavior (elastic modulus: ca. 60 kPa; fatigue life: >5000 cycles; mechanically stable at temperatures up to 200 °C). The activation energy of ionic conductivity was shown to be nearly identical for the ionogel and the neat IL, in contrast to ionogel systems wherein the scaffold material is miscible with the IL. This similarity indicates that IL/scaffold chemical interactions are key to the understanding of ionogel electrical performance, especially at elevated temperatures.

Unplanned reoperations: is emergency surgery a risk factor? A cohort study.

BACKGROUND: Unplanned reoperations have been proposed as a quality indicator in surgery but have not been studied extensively, especially concerning risk factors. METHODS: This was a prospective cohort study in a third-level general surgery service. Data regarding patients operated on between July 2007 and February 2008 and followed up for 30 postoperative days were collected. Unplanned reoperations were the primary end point. The secondary end points were 30-d mortality and length of stay. A multivariate logistic regression analysis evaluated the hypothesis that patients operated on in emergency conditions had a greater chance of being reoperated on, after adjusting for relevant covariates. RESULTS: There was a 5.9% cumulative incidence of unplanned reoperations. Patients operated on in emergency conditions had a 1.79 crude relative risk (RR) (95% confidence interval [CI], 1.15-2.78) of reoperation. Reoperated patients' RR of mortality was 8.94 (95% CI, 6.11-13.07). The mean postoperative hospital stay was 3d for patients who were not reoperated on and 19d for those who were reoperated on (P=0.00001). The logistic regression model gave a 2.83 odds ratio (95% CI, 1.65-4.87) for reoperation on emergency patients when adjusted for age, gender, body mass index, American Society of Anesthesiology classification, intraoperative inotropic use, and operation complexity. CONCLUSIONS: Tertiary general surgery service patients had a significantly increased risk of being reoperated on if the initial surgery was an emergency surgery compared with elective surgery. Unplanned reoperations led to a significantly increased mortality risk and a longer postoperative hospital stay, which could be regarded as warning signs in the care of surgical patients.

Cryptic speciation within Asthenodipsas vertebralis (Boulenger, 1900) (Squamata: Pareatidae), the description of a new species from Peninsular Malaysia, and the resurrection of A. tropidonotus (Lidth de Jude, 1923) from Sumatra: an integrative taxonomic analysis.

A review of the taxonomic status of the Asian Slug Snake, Asthenodipsas vertebralis (Boulenger, 1900) based on an integrative taxonomic approach using molecular, morphological, color pattern, and ecological data indicate it is composed of three well supported monophyletic lineages: (1) Pulau Tioman and Fraser's Hill, Pahang and Bukit Larut, Perak; Peninsular Malaysia; (2) its sister lineage from Northern Sumatra; and (3) the remaining basal lineage from Peninsular Malaysia. Furthermore, we consider the high sequence divergence (6.3%-10.2%) between these lineages (especially in areas of sympatry) and discrete differences in their morphology, color pattern, and microhabitat preference as evidence they are not conspecific. As such, we resurrect the name A. tropidonotus (Lidth de Jeude, 1923) for the Sumatra populations, restrict the name A. vertebralis to the populations from Pulau Tioman, Genting Highlands, Fraser's Hill, Gunung Benom, and Bukit Larut that contain terrestrial, banded adults; and consider A. lasgalenensis sp. nov. to be restricted to the populations from Fraser's Hill, Cameron Highlands, and Bukit Larut that contain arboreal, unbanded adults.

A new species of karst-adapted Cnemaspis Strauch, 1887 (Squamata: Gekkonidae) from a threatened karst region in Pahang, Peninsular Malaysia.

A new species of karst-adapted gekkonid lizard of the genus Cnemaspis Strauch is described from Gua Gunting and Gua Goyang in a karst region of Merapoh, Pahang, Peninsular Malaysia whose unique limestone formations are in immediate danger of being quarried. The new species differs from all other species of Cnemaspis based on its unique suite of morphological and color pattern characters. Its discovery underscores the unique biodiversity endemic to karst regions and adds to a growing list of karst-adapted reptiles from Peninsular Malaysia. We posit that new karst-adapted species endemic to limestone forests will continue to be discovered and these regions will harbor a significant percentage of Peninsular Malaysia's biodiversity and thusly should be conserved rather than quarried.

Longitudinal examination of perfusion and angiogenesis markers in primary colorectal tumors shows distinct signatures for metronomic and maximum-tolerated dose strategies.

Metronomic chemotherapy (MET) has been developed to address the shortcomings of maximum-tolerated chemotherapy (MTD) in regard to toxicity and development of resistance mechanisms in the tumor. In colorectal cancer (CRC), MET is a promising novel strategy to treat locally advanced malignancies when used as neoadjuvant chemotherapy (NAC). However, so far there are no preclinical studies to assess the impact of MET NAC in CRC to assess the benefits and challenges of this approach. Here, we used a primary model of CRC (via azoxymethane) to analyze longitudinal changes in angiogenesis in primary tumors under MET and MTD NAC using a combination of diffuse reflectance spectroscopy and mRNA expression (via qPCR). Our results show that MET and MTD NAC lead to increased mean tissue oxygen saturation (8% and 5%, respectively) and oxyhemoglobin (15% and 10%) between weeks 2 and 5 of NAC, and that such increases are caused by distinct molecular signatures in the angiogenic program. Specifically, we find that in the MET group there is a sustained increase in Hif-1a, Aldoa, and Pgk1 expression, suggesting upregulated glycolysis, whereas MTD NAC causes a significant reduction in the expression of the aforementioned genes and of Vegf, leading to vascular remodeling in MTD-treated tumors. Taken together, this study demonstrates the ability of combined optical and molecular methodologies to provide a holistic picture of tumor response to therapy in CRC in a minimally invasive manner.

Minimally invasive in vivo endoscopic monitoring of dextran sulfate sodium-induced murine colitis.

Ulcerative colitis (UC) is a gastrointestinal, autoimmune disease that causes ulceration and inflammation of the colon with an incidence of 10 out of every 100,000 people in North America and Western Europe. Though the specific cause is unknown, several studies have demonstrated that inflammatory cells as well as environmental variables, genetics, and lifestyle behaviors can play a role in the long-term inflammatory response. Researchers have commonly used immunohistochemistry, western blotting and gene sequencing to establish the cellular processes behind UC relapse and remission. However, because these destructive methods necessitate the removal of a sample, they can only be used on non-living tissues. The use of minimally invasive approaches to evaluate the in vivo, longitudinal effects of UC on the mucosa in the colon is gaining popularity among clinicians and researchers. We have created a dextran sulfate sodium-induced model of UC in C57 mice based on the work of Wirtz et al., and a minimally invasive imaging modality to explore the changes in mucosal tissue during "active" and "in remission" UC. Briefly, C57 mice were given dextran sulfate sodium (DSS) dissolved in water in 5-day cycles with a remission/recovery period of 10 days. After 7 days post-DSS treatment and 7 days post-recovery, mice were anesthetized and exploratory endoscopies were performed to assess the mucosal changes that occur during the "active" and "remission" periods of UC. Value of protocol:•Minimally invasive induction of ulcerative colitis in a murine mouse model.•Minimally invasive longitudinal monitoring of "active" and "in remission" ulcerative colitis.•Our endoscopic based imaging modality can be used to validate the induction of ulcerative colitis and the potential treatment response for pre-clinical trials.

Molecular and Serologic Diagnostic Technologies for SARS-CoV-2.

The COVID-19 pandemic has presented many challenges that have spurred biotechnological research to address specific problems. Diagnostics is one area where biotechnology has been critical. Diagnostic tests play a vital role in managing a viral threat by facilitating the detection of infected and/or recovered individuals. From the perspective of what information is provided, these tests fall into two major categories, molecular and serological. Molecular diagnostic techniques assay whether a virus is present in a biological sample, thus making it possible to identify individuals who are currently infected. Additionally, when the immune system is exposed to a virus, it responds by producing antibodies specific to the virus. Serological tests make it possible to identify individuals who have mounted an immune response to a virus of interest and therefore facilitate the identification of individuals who have previously encountered the virus. These two categories of tests provide different perspectives valuable to understanding the spread of SARS-CoV-2. Within these categories, different biotechnological approaches offer specific advantages and disadvantages. Here we review the categories of tests developed for the detection of the SARS-CoV-2 virus or antibodies against SARS-CoV-2 and discuss the role of diagnostics in the COVID-19 pandemic.

Placenta accreta is associated with IVF pregnancies: a retrospective chart review.

OBJECTIVE: To study the association between placenta accreta (PA) and in vitro fertilisation (IVF) pregnancies. DESIGN: Retrospective chart review. SETTING: Tertiary care centre in Jerusalem, Israel. SAMPLE: During January 2004-February 2009, 25,193 deliveries occurred in our hospital, including 752 (3%) deliveries of IVF pregnancies. METHODS: Placenta accreta was only diagnosed when there were histological findings from the placenta associated with the suitable clinical course. Demographic, obstetrical and fertility characteristics of these patients were retrieved from hospital files. MAIN OUTCOME MEASURE: Rates of PA in pregnancies achieved with IVF versus rates of PA in spontaneous pregnancies. RESULTS: The rate of PA in the IVF group was 12/752 (16/1000) pregnancies, compared with 30/24,441 (1.2/1000) among spontaneous pregnancies (P < 0.0001; OR 13.2; 95% CI 6.7-25.8). Among the variables examined, parity, rate of caesarean delivery in the index pregnancy, and birthweight differed significantly between IVF and spontaneous pregnancies. CONCLUSIONS: The odds of developing PA are significantly higher in IVF pregnancies than in spontaneous pregnancies. These differences may stem from differences in the endometrial environment, or from changes to the endometrium wrought by IVF treatment protocols.

Diffuse reflectance spectroscopy to monitor murine colorectal tumor progression and therapeutic response (Erratum).

The erratum notes a correction to Fig. 5 for the published article.

Diffuse reflectance spectroscopy to monitor murine colorectal tumor progression and therapeutic response.

SIGNIFICANCE: Many studies in colorectal cancer (CRC) use murine ectopic tumor models to determine response to treatment. However, these models do not replicate the tumor microenvironment of CRC. Physiological information of treatment response derived via diffuse reflectance spectroscopy (DRS) from murine primary CRC tumors provide a better understanding for the development of new drugs and dosing strategies in CRC. AIM: Tumor response to chemotherapy in a primary CRC model was quantified via DRS to extract total hemoglobin content (tHb), oxygen saturation (StO2), oxyhemoglobin, and deoxyhemoglobin in tissue. APPROACH: A multimodal DRS and imaging probe (0.78 mm outside diameter) was designed and validated to acquire diffuse spectra longitudinally-via endoscopic guidance-in developing colon tumors under 5-fluoruracil (5-FU) maximum-tolerated (MTD) and metronomic regimens. A filtering algorithm was developed to compensate for positional uncertainty in DRS measurements Results: A maximum increase in StO2 was observed in both MTD and metronomic chemotherapy-treated murine primary CRC tumors at week 4 of neoadjuvant chemotherapy, with 21 ± 6 % and 17 ± 6 % fold changes, respectively. No significant changes were observed in tHb. CONCLUSION: Our study demonstrates the feasibility of DRS to quantify response to treatment in primary CRC models.

Multicell simulations of development and disease using the CompuCell3D simulation environment.

Mathematical modeling and computer simulation have become crucial to biological fields from genomics to ecology. However, multicell, tissue-level simulations of development and disease have lagged behind other areas because they are mathematically more complex and lack easy-to-use software tools that allow building and running in silico experiments without requiring in-depth knowledge of programming. This tutorial introduces Glazier-Graner-Hogeweg (GGH) multicell simulations and CompuCell3D, a simulation framework that allows users to build, test, and run GGH simulations.