Interventions Effective in Decreasing Burden in Caregivers of Persons with Dementia: A Meta-Analysis

Introduction: Chronic non-communicable diseases, including diseases of mental origin such as Alzheimer's, affect all age groups and countries. These diseases have a major impact on the patient and their family environment. It is interesting that different questionnaires are measured in the same direction, given that different health questionnaires are used to measure caregiver burden. Objectives: To identify which type of intervention is the most appropriate to improve the health of the primary caregiver in patients with dementia. To understand the role played by the nurse within multidisciplinary teams and to know whether the different questionnaires used in the studies measure caregiver health in the same direction. Methods: A systematic search of the published and gray literature was carried out without restriction of the language used in the studies. Caregiver burden of patients with dementia, receiving an intervention to improve caregiver burden, was assessed. Standardized mean difference was used as the effect size measure, and there were possible causes of heterogeneity in the effect size. Results: In total, 1512 records were found, and 39 articles with 4715 participants were included. We found individual information with an effect of 0.48 (CI95%: 0.18; 0.79; I2 = 0%); group therapy with an effect of 0.20 (CI95%: 0.08; 0.31; I2 = 6%); workshops with an effect of 0.21 (CI95%: 0.01; I2 = 48%) and 0.32 (CI95%: 0.01; 0.54; I2 = 0%) when a nurse intervenes; respite care with an effect of 0.22 (CI95%: 0.05; 0.40; I2 = 66%); individual therapy with an effect of 0.28 (CI95%: 0.15; 0.4; I2 = 68%); and support groups with an effect of 0.07 (CI95%: 0; 0.15; I2 = 78%). Conclusions: The magnitude of the effects of the interventions has been low-moderate. Different instruments are not associated with the magnitude of the effect. The presence of nurses improves the effect of the intervention on caregivers when it is carried out in the form of workshops.

Effects of Physical Exercise on Telomere Length in Healthy Adults: Systematic Review, Meta-Analysis, and Meta-Regression

BACKGROUND

Physical exercise is one of the main nonpharmacological treatments for most pathologies. In addition, physical exercise is beneficial in the prevention of various diseases. The impact of physical exercise has been widely studied; however, existing meta-analyses have included diverse and heterogeneous samples. Therefore, to our knowledge, this is the first meta-analysis to evaluate the impact of different physical exercise modalities on telomere length in healthy populations.

OBJECTIVE

In this review, we aimed to determine the effect of physical exercise on telomere length in a healthy population through a meta-analysis of randomized controlled trials.

METHODS

A systematic review with meta-analysis and meta-regression of the published literature on the impact of physical exercise on telomere length in a healthy population was performed. PubMed, Cochrane Library, SCOPUS, Web of Science, and Embase databases were searched for eligible studies. Methodological quality was evaluated using the Risk Of Bias In Nonrandomized Studies of Interventions and the risk-of-bias tool for randomized trials. Finally, the certainty of our findings (closeness of the estimated effect to the true effect) was evaluated using Grading of Recommendations, Assessment, Development, and Evaluations (GRADE).

RESULTS

We included 9 trials that met the inclusion criteria with fair methodological quality. Random-effects model analysis was used to quantify the difference in telomere length between the exercise and sham groups. Meta-analysis showed that exercise did not significantly increase telomere length compared with the control intervention (mean difference=0.0058, 95% CI -0.05 to 0.06; P=.83). Subgroup analysis suggested that high-intensity interventional exercise significantly increased telomere length compared with the control intervention in healthy individuals (mean difference=0.15, 95% CI 0.03-0.26; P=.01). Furthermore, 56% of the studies had a high risk of bias. Certainty was graded from low to very low for most of the outcomes.

CONCLUSIONS

The findings of this systematic review and meta-analysis suggest that high-intensity interval training seems to have a positive effect on telomere length compared with other types of exercise such as resistance training or aerobic exercise in a healthy population.

TRIAL REGISTRATION

PROSPERO CRD42022364518; http://tinyurl.com/4fwb85ff.

SLEEP quality in patients with psoriatic arthritis and its relationship with disease activity and comorbidities: a cross-sectional study

The assessment of psoriatic arthritis is complex and multidimensional. It is increasingly common to include the patient perspective using patient-reported outcomes. Although some research has explored sleep quality in patients with psoriatic arthritis, most studies have had small sample sizes, failed to assess sleep quality considering the inflammatory process together with the psychological well-being of patients, and have not described any use of sleep medication. Further, research to date has not provided data on the relationship of sleep quality with axial forms. In this context, the objective of this study was to assess sleep quality in patients with psoriatic arthritis and its relationship with clinical characteristics, disease activity, functioning, disease impact, fatigue and psychological status. A cross-sectional study was conducted including 247 consecutive patients with PsA recruited during 2021. Sleep quality was measured using the Pittsburgh Sleep Quality Index. We assessed correlations of Pittsburgh Sleep Quality Index score with peripheral disease activity (Disease Activity Index for PSoriatic Arthritis), axial disease activity (Ankylosing Spondylitis Disease Activity Score-C-reactive protein and Bath Ankylosing Spondylitis Disease Activity Index), functioning (Bath Ankylosing Spondylitis Functional Index and Health Assessment Questionnaire), impact (Psoriatic Arthritis Impact of Disease questionnaire), anxiety, depression (Hospital Anxiety and Depression Scale) and fatigue (Functional Assessment of Chronic Illness Therapy-Fatigue) scores. A multiple linear regression model was constructed with PSQI as the dependent variable and as independent variables those that could influence sleep quality. Nearly two-thirds (63.15%) of patients had poor sleep quality. Poorer sleep quality was associated with being female, higher joint counts, greater peripheral and axial disease activity, fatigue, anxiety and depression, functioning and disease impact (p < 0.001). Multiple linear regression analysis found that pain (β: 0.3; p < 0.007) and fatigue β: - 0.1; p < 0.001 contributed 40% to the sleep quality model. Poor sleep quality was common among patients with psoriatic arthritis. Emotional factors (fatigue, anxiety) seemed more important than inflammatory factors in sleep quality.

Superficial spreading cervical squamous cell carcinoma in situ involving the endometrium: a case report and review of the literature

BACKGROUND

The spread of cervical squamous cell carcinoma to the inner surface of the uterus with replacement of the endometrium is rare. Continuity of the lesion must be demonstrated to confirm superficial spread and rule out concomitant endometrial cancer.

CASE PRESENTATION

We present the case of a 66-year-old white woman with superficial spreading squamous cell carcinoma of the cervix that involved the endometrium. Her relevant past history included conization of the cervix to treat cervical intraepithelial neoplasia III with positive margins. She subsequently had three negative cervical vaginal cytology results, each with a positive high-risk human papillomavirus test. Transvaginal ultrasound showed occupation of the entire uterine cavity by dense material consistent with pyometra in addition to myometrial thinning due to tension and cervical dilation. The patient presented with greenish vaginal discharge of 3 months' duration. The cervix was not visible during speculum examination. Access for endometrial sampling was not possible, raising suspicion of post-conization cervical stenosis. The patient was treated with laparoscopic hysterectomy with double adnexectomy. Histologic examination showed superficial squamous cell carcinoma invading the cervix to a depth of 2.8 mm; superficial spreading squamous cell carcinoma in situ was also observed in the lower uterine segment and endometrium. The patient was free of symptoms 12 months after surgery.

CONCLUSIONS

Squamous cell carcinoma of the cervix with superficial spread to the endometrium is not included in the 2020 (fifth edition) World Health Organization Classification of Female Genital Tract Tumors or the 2018 International Federation of Gynecology and Obstetrics cervical cancer staging system. More clinical cases are needed to identify other prognostic factors and inform clinical practice guidelines on the management of this disease.

Early recurrence of aggressive leiomyosarcoma of the vagina

Malignant mesenchymal tumors of the female genital tract are uncommon gynecological cancers, particularly in the vagina. They are typically aggressive and often relapse, both locally and at distant sites. The treatment of choice for primary tumors is surgical excision as they are generally refractory to chemotherapy and radiotherapy. We describe the case of a vaginal leiomyosarcoma in a 43-year-old woman who presented with abnormal genital bleeding and discharge. The tumor was excised but recurred locally after just 11 months. It was removed by hysterectomy with double adnexectomy and partial vaginal excision.

Association between genetic variants in oxidative stress-related genes and osteoporotic bone fracture. The Hortega follow-up study

The most widely accepted etiopathogenesis hypothesis of the origin of osteoporosis and its complications is that they are a consequence of bone aging and other environmental factors, together with a genetic predisposition. Evidence suggests that oxidative stress is crucial in bone pathologies associated with aging. The aim of this study was to determine whether genetic variants in oxidative stress-related genes modified the risk of osteoporotic fracture. We analysed 221 patients and 354 controls from the HORTEGA sample after 12-14 years of follow up. We studied the genotypic and allelic distribution of 53 SNPs in 24 genes involved in oxidative stress. The results showed that being a carrier of the variant allele of the SNP rs4077561 within TXNRD1 was the principal genetic risk factor associated with osteoporotic fracture and that variant allele of the rs1805754 M6PR, rs4964779 TXNRD1, rs406113 GPX6, rs2281082 TXN2 and rs974334 GPX6 polymorphisms are important genetic risk factors for fracture. This study provides information on the genetic factors associated with oxidative stress which are involved in the risk of osteoporotic fracture and reinforces the hypothesis that genetic factors are crucial in the etiopathogenesis of osteoporosis and its complications.

Effects of Physical Exercise on Cognition and Telomere Length in Healthy Older Women

BACKGROUND

Physical exercise is an effective measure for preventing the onset of cognitive decline and has a direct influence on the aging process. The purpose of this study was to assess the effect of a 6-month physical exercise program on cognition and telomere length in adults over 65 years of age.

METHOD

Seventy-four healthy women were separated into two groups: 41 were included in the intervention group (IG) (72.70 ± 4.127 years and 8.18 ± 1.551 years of education) and 33 in the control group (CG) (71.21 ± 4.127 years and 8.42 ± 2.562). The participants included within the IG carried out three sessions of physical exercise per week for six months. Cognitive function was assessed using the Mini-Mental State Examination (MMSE), the Stroop test and the Trail Making Test (TMT). Saliva samples were taken and analyzed and relative telomere length was calculated. Those conducting the analysis were blind to the group to which the participants had been assigned.

RESULTS

An improvement was observed in global cognitive function, in both attentional and executive functions, in the group of adults doing physical exercise as compared to the control group. Six months after the physical exercise program had finished, relative telomere length was found to have increased in the participants in the intervention group.

CONCLUSION

Physical exercise programs can lead to an improvement in both cognitive functions and telomere length.

Intestinal-type adenocarcinoma of the Bartholin gland: A case report and literature review

•

This entity has pathological characteristics identical to mucinous colorectal carcinoma.

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KRAS mutations are observed in approximately 40% of colorectal cancers.

•

The treatment and management may not differ from that of squamous cell carcinomas.

Purpose

To report a case of intestinal-type adenocarcinoma of the Bartholin gland treated successfully with surgery and to review the current literature.

Methods

We report the case of a 45-year-old white woman with intestinal-type adenocarcinoma of the Bartholin gland treated with wide local excision followed by bilateral inguinal femoral lymph node dissection without adjuvant therapy. We also review the literature on the treatment and management of this rare tumor. We searched Pubmed / MEDLINE databases for previous case reports or series using the keywords “Bartholin gland”, “adenocarcinoma” and “intestinal type”.

Results

We found 19 cases of intestinal-type adenocarcinoma of the Bartholin gland published up to November 2020. The treatments described varied from case to case.

Conclusion

Intestinal-type adenocarcinoma of the Bartholin gland has been treated and managed in the same way as squamous carcinoma. Treatment of these cancers is understudied and involves local resection with curative intent. More case reports are needed to determine the best treatment strategies.

[Active surveillance for patients with localized prostate cáncer. Adherence and protocol drop analysis.]

OBJECTIVE

VA is currently considered the treatment of choice for patients with low and very low risk prostate cancer. We analyzed the evolution of this treatment strategy in our series and adherence to the protocol.

MATERIAL AND METHODS

Ambispective study of patients in VA in our center between 2014- 2019. 237 meet inclusion criteria, of which 142 (60%) have a minimum of 12 months of follow- up. Mean age: 68.5 (4678), median PSA 6.37 ng / ml (1-33). 229 (96.6%) are ISUP 1 and 8 (3.4%) ISUP 2. Objectives are proposed to assess our adherence to the protocol. Descriptive statistics are used to communicate the results.

RESULTS

According to the classification by risk groups of the NCCN, 145 (61.2%), 49 (20.7%) and 42 (17.7%) were very low risk, low risk and favorable intermediate risk patients, respectively. The median of follow-up is 14 months (0-66). Of the patients with a minimum follow-up of 12 months, 107 (75.4%) were re-biopsied. 80 (33.8%) leave the protocol in these 5 years, 31.3% (25) by their own decision, 55% (44) due to medical criteria, and 11.3% (9) go to WW. After 5 years of follow-up, 99.2% of patients are still alive, 0.8% died of specific non-cancer causes. Of the objectives to assess adherence, 8 are achieved, 1 partially and 1 is not evaluable.

CONCLUSIONS

VA in our center is already the treatment of choice for very low-risk patients, with a constant increase from year to year. Adherence to the protocol has been favorable during the period of time studied.

VAV3 rs7528153 and VAV3-AS1 rs1185222 polymorphisms are associated with an increased risk of developing hypertension

The aetiology of essential hypertension is complex and involves both environmental and genetic factors. Approximately 30% of the inter-individual variability in blood pressure is genetically determined. It has been shown that numerous vasoconstrictors stimulate RhoA in local populations of vascular SMCs that, in turn, promote localised constriction of arterial blood vessels and elevations in blood pressure. The VAV3 gene encodes for VAV3 protein, a Rho GEF factor. VAV3-AS1 gene, a lncRNA, may regulate VAV3 expression. We performed an observational prospective case-control study, including patients attending in the Vascular Risk Unit from the University Hospital Salamanca for 6 months. A replication study was performed with data from The Kaiser Permanent database of the University of California. The results suggest that T allele of the VAV3 rs7528153 and G allele of the VAV3-AS1 rs11185222 polymorphisms are associated with an increased risk of developing hypertension. We hypothesise that these polymorphisms could modify blood pressure, likely through a modification in the Rho/Rac pathway. Our results suggest that those polymorphisms could be useful genetic markers of susceptibility to suffering hypertension.

Isolated fallopian tube torsion associated with hydrosalpinx in a 12-year-old girl: a case report

Background

Isolated fallopian tube torsion associated with hydrosalpinx is a rare condition in the pediatric population. We present this unusual clinical case study in a sexually inactive girl.

Case presentation

a12-year-old Caucasian girl presented symptoms of acute abdominal pain. Pelvic ultrasound revealed a normal looking uterus and ovaries and next to left ovary a imaging compatible with hydrosalpinx. She was discharged 48 hours later after clinical monitoring with oral analgesia and normal blood workup. At 3 weeks, she was readmitted for acute abdominal pain. Leukocytosis with left shift and raised C-reactive protein were observed. Her clinical condition worsened, and complication of the preexisting hydrosalpinx was suspected. Exploratory laparoscopy confirmed torsion of the fallopian tube. Left salpingectomy was performed. Histopathologic study confirmed a fallopian tube with hemorrhagic infarct.

Conclusion

Torsion of the fallopian tube must be considered in the event of acute abdominal pain. Early diagnosis and trying conservative management with a view to preserving fertility in this group of patients are essential.

Polymorphisms in genes involved in inflammation, the NF-kB pathway and the renin-angiotensin-aldosterone system are associated with the risk of osteoporotic fracture. The Hortega Follow-up Study

Osteoporosis is the most common bone disorder worldwide and is associated with a reduced quality of life with important clinical and economic consequences. The most widely accepted etiopathogenic hypothesis on the origin of osteoporosis and its complications is that they are a consequence of the synergic action of environmental and genetic factors. Bone is constantly being remodelled through anabolic and catabolic pathways in which inflammation, the NF-kB pathway and the renin-angiotensin-aldosterone system (RAAS) are crucial. The aim of our study was to determine whether polymorphisms in genes implicated in inflammation, the NF-kB pathway and RAAS modified the risk of osteoporotic fracture. We analysed 221 patients with osteoporotic fracture and 354 controls without fracture from the HORTEGA sample after 12-14 years of follow up. In addition, we studied the genotypic distribution of 230 single nucleotide polymorphisms (SNPs) in genes involved in inflammation, NF-kB pathway and RAAS. Our results showed that be carrier of the C allele of the rs2228145 IL6R polymorphism was the principal genetic risk factor associated with osteoporotic fracture. The results also showed that variant genotypes of the rs4762 AGT, rs4073 IL8, rs2070699 END1 and rs4291 ACE polymorphisms were important genetic risk factors for fracture. The study provides information about the genetic factors associated with inflammation, the NF-kB pathway and RAAS, which are involved in the risk of osteoporotic fracture and reinforces the hypothesis that genetic factors are crucial in the etiopathogenesis of osteoporosis and its complications.

Real-life experience with Dulaglutide: Analysis of clinical effectiveness to 24 months

OBJECTIVE

Dulaglutide is an agonist of "glucagon-like peptide type 1″ receptors (arGLP1). The clinical efficacy of this molecule is based on reductions in glycosylated hemoglobin (HbA1c) and weight, data shown in the pivotal AWARD studies.

METHODS

We propose a retrospective and multicenter study that allows evaluating the effectiveness of dulaglutide at 24 months after treatment began, under conditions of usual clinical practice, and comparing the results obtained with those that are reflected in the controlled trials.

RESULTS

The results show a reduction in the HbA1c levels -1.4% at 6 M and this reduction were maintained throughout 12 M and 24 M (p < 0.001). Plasma glucose showed significant reductions around -30 mg / dL at 6 months (p < 0.001) that remained until the end of the follow-up at 12 and 24 M, respectively. The weight decreased significantly at 6 M (p < 0.001) but continued decreasing at 12 and 24 M, showing statistically significant differences (p: 0.001).

CONCLUSIONS

Our results are similar to those obtained in pivotal clinical trials and confirm these benefits in real life.

New Deep Learning Genomic-Based Prediction Model for Multiple Traits with Binary, Ordinal, and Continuous Phenotypes

Multiple-trait experiments with mixed phenotypes (binary, ordinal and continuous) are not rare in animal and plant breeding programs. However, there is a lack of statistical models that can exploit the correlation between traits with mixed phenotypes in order to improve prediction accuracy in the context of genomic selection (GS). For this reason, when breeders have mixed phenotypes, they usually analyze them using univariate models, and thus are not able to exploit the correlation between traits, which many times helps improve prediction accuracy. In this paper we propose applying deep learning for analyzing multiple traits with mixed phenotype data in terms of prediction accuracy. The prediction performance of multiple-trait deep learning with mixed phenotypes (MTDLMP) models was compared to the performance of univariate deep learning (UDL) models. Both models were evaluated using predictors with and without the genotype × environment (G×E) interaction term (I and WI, respectively). The metric used for evaluating prediction accuracy was Pearson's correlation for continuous traits and the percentage of cases correctly classified (PCCC) for binary and ordinal traits. We found that a modest gain in prediction accuracy was obtained only in the continuous trait under the MTDLMP model compared to the UDL model, whereas for the other traits (1 binary and 2 ordinal) we did not find any difference between the two models. In both models we observed that the prediction performance was better for WI than for I. The MTDLMP model is a good alternative for performing simultaneous predictions of mixed phenotypes (binary, ordinal and continuous) in the context of GS.

VEGFR2 and OPG genes modify the risk of subclinical coronary atherosclerosis in patients with familial hypercholesterolemia

BACKGROUND AND AIMS

Heterozygous familial hypercholesterolemia (FH) is a genetic disorder characterized by high levels of low-density lipoprotein cholesterol (LDL-C). The magnitude of atherosclerotic cardiovascular disease (ASCVD) risk in FH patients is highly variable, and this can result from genetic factors. The aim of our study was to characterize whether polymorphisms in VEGFR2 and OPG genes could influence the expression of ASCVD in FH patients.

METHODS

We studied 318 FH patients from the SAFEHEART registry, without clinical diagnosis of ASCVD. A coronary tomographic angiography (CTA) was performed to determine and evaluate the presence of coronary stenosis and coronary artery calcium, as measured by coronary calcium score (CCS). Genotyping of OPG rs2073618 and VEGFR2 rs2071559 polymorphisms was performed using TaqMan 5'-exonuclease allelic discrimination assays.

RESULTS

Homozygous GG genotype and G allele of VEGFR2 rs2071559 polymorphism were associated with decreased risk of developing coronary artery stenosis. In the analysis of OPG rs2073618 and VEGFR2 rs2071559 polymorphisms, according to the presence of coronary artery calcium, we found significant differences in both polymorphisms. Homozygous GG genotype and G allele of VEGFR2 rs2071559 polymorphism were associated with decreased risk of accumulation of coronary artery calcium measured by CCS in CTA. Moreover, being a carrier of the GG genotype and G allele of the OPG rs2073618 polymorphism increased the risk of the presence of coronary artery calcium measured by CCS in CTA.

CONCLUSIONS

Polymorphisms in VEGFR2 and OPG genes modify the risk of ASCVD in FH patients.

A Benchmarking Between Deep Learning, Support Vector Machine and Bayesian Threshold Best Linear Unbiased Prediction for Predicting Ordinal Traits in Plant Breeding

Genomic selection is revolutionizing plant breeding. However, still lacking are better statistical models for ordinal phenotypes to improve the accuracy of the selection of candidate genotypes. For this reason, in this paper we explore the genomic based prediction performance of two popular machine learning methods: the Multi Layer Perceptron (MLP) and support vector machine (SVM) methods vs. the Bayesian threshold genomic best linear unbiased prediction (TGBLUP) model. We used the percentage of cases correctly classified (PCCC) as a metric to measure the prediction performance, and seven real data sets to evaluate the prediction accuracy, and found that the best predictions (in four out of the seven data sets) in terms of PCCC occurred under the TGLBUP model, while the worst occurred under the SVM method. Also, in general we found no statistical differences between using 1, 2 and 3 layers under the MLP models, which means that many times the conventional neuronal network model with only one layer is enough. However, although even that the TGBLUP model was better, we found that the predictions of MLP and SVM were very competitive with the advantage that the SVM was the most efficient in terms of the computational time required.

Multi-trait, Multi-environment Deep Learning Modeling for Genomic-Enabled Prediction of Plant Traits

Multi-trait and multi-environment data are common in animal and plant breeding programs. However, what is lacking are more powerful statistical models that can exploit the correlation between traits to improve prediction accuracy in the context of genomic selection (GS). Multi-trait models are more complex than univariate models and usually require more computational resources, but they are preferred because they can exploit the correlation between traits, which many times helps improve prediction accuracy. For this reason, in this paper we explore the power of multi-trait deep learning (MTDL) models in terms of prediction accuracy. The prediction performance of MTDL models was compared to the performance of the Bayesian multi-trait and multi-environment (BMTME) model proposed by Montesinos-López et al. (2016), which is a multi-trait version of the genomic best linear unbiased prediction (GBLUP) univariate model. Both models were evaluated with predictors with and without the genotype×environment interaction term. The prediction performance of both models was evaluated in terms of Pearson's correlation using cross-validation. We found that the best predictions in two of the three data sets were found under the BMTME model, but in general the predictions of both models, BTMTE and MTDL, were similar. Among models without the genotype×environment interaction, the MTDL model was the best, while among models with genotype×environment interaction, the BMTME model was superior. These results indicate that the MTDL model is very competitive for performing predictions in the context of GS, with the important practical advantage that it requires less computational resources than the BMTME model.

Rapid growth rate is associated with poor prognosis in cutaneous squamous cell carcinoma

BACKGROUND

Cutaneous squamous cell carcinoma (cSCC) represents the most common form of skin cancer after basal cell carcinoma, and can be both locally invasive and metastatic to distant sites. Growth rate (GR) has been poorly evaluated in cSCC, despite clinical evidence suggesting that GR is an important risk factor in cSCC.

AIM

To analyse the influence of GR in cSCC prognosis.

METHODS

We retrospectively evaluated GR in a series of 90 cSCCs and tried to correlate GR with prognosis in cSCC.

RESULTS

We demonstrated that tumours with a GR of > 4 mm/month exhibit a higher risk of nodal progression and a shorter progression time to lymph node metastasis in cSCC than those with GR of < 4 mm/month. As expected, GR correlated with tumour proliferation, as determined by Ki-67 expression.

CONCLUSIONS

We consider a GR of 4 mm/month as the cutoff point that distinguishes between rapid- and slow-progressing tumours and, more importantly, to identify a subset of high-risk cSCCs.

Introducing Meta-Partition, a Useful Methodology to Explore Factors That Influence Ecological Effect Sizes

The study of the heterogeneity of effect sizes is a key aspect of ecological meta-analyses. Here we propose a meta-analytic methodology to study the influence of moderators in effect sizes by splitting heterogeneity: meta-partition. To introduce this methodology, we performed a meta-partition of published data about the traits that influence species sensitivity to habitat loss, that have been previously analyzed through meta-regression. Thus, here we aim to introduce meta-partition and to make an initial comparison with meta-regression. Meta-partition algorithm consists of three steps. Step 1 is to study the heterogeneity of effect sizes under the assumption of fixed effect model. If heterogeneity is found, we perform step 2, that is, to partition the heterogeneity by the moderator that minimizes heterogeneity within a subset while maximizing heterogeneity between subsets. Then, if effect sizes of the subset are still heterogeneous, we repeat step 1 and 2 until we reach final subsets. Finally, step 3 is to integrate effect sizes of final subsets, with fixed effect model if there is homogeneity, and with random effects model if there is heterogeneity. Results show that meta-partition is valuable to assess the importance of moderators in explaining heterogeneity of effect sizes, as well as to assess the directions of these relations and to detect possible interactions between moderators. With meta-partition we have been able to evaluate the importance of moderators in a more objective way than with meta-regression, and to visualize the complex relations that may exist between them. As ecological issues are often influenced by several factors interacting in complex ways, ranking the importance of possible moderators and detecting possible interactions would make meta-partition a useful exploration tool for ecological meta-analyses.

Population density in Podarcis lilfordi (Squamata, Lacertidae), a lizard species endemic to small islets in the Balearic Islands (Spain)

Abstract

The Balearic lizard, Podarcis lilfordi, is present in 43 insular populations in the Cabrera archipelago and around the coasts of Mallorca and Menorca islands (Spain). We studied lizard densities over the entire range of distribution, analyzing observed differences of density in relation to island area, habitat diversity, availability of resources, presence of predators, competitors and human disturbances. The density of the Balearic lizard varies from less than 35 to almost 8000 lizards ha–1, with an average of around 1500 lizards ha–1. In some very small islets we detected no more than 10 individuals. Using a subsample of nine coastal islets (Menorca) we did not find any significant correlation between ground arthropod biomass and lizard density. The combination of island area and its maximal altitude, its so-called biotic capacity, was also uncorrelated with lizard density. In addition, neither degree of island accessibility nor presence/absence of seagull breeding colonies, were able to explain lizard densities. Islands without ship rats (Rattus rattus) showed a significantly higher lizard density, but islands in which rat eradication programs were launched during the study period, showed lower densities than those with rats but no eradication actions. Genetic variability was significantly higher on bigger lizard populations, lacking a correlation with lizard densities. No single independent variable can explain density differences among populations under study. Our results are discussed in the light of available hypotheses on factors affecting population densities.