Neuropsychopathological comorbidities in learning disorders

Background

Learning Disorders (LD) are complex diseases that affect about 2-10% of the school-age population. We performed neuropsychological and psychopathological evaluation, in order to investigate comorbidity in children with LD.

Methods

Our sample consisted of 448 patients from 7 to 16 years of age with a diagnosis of LD, divided in two subgroups: Specific Learning Disorders (SLD), including reading, writing, mathematics disorders, and Learning Disorders Not Otherwise Specified (LD NOS).

Results

Comorbidity with neuropsychopathologies was found in 62.2% of the total sample. In the LSD subgroup, ADHD was present in 33%, Anxiety Disorder in 28.8%, Developmental Coordination Disorder in 17.8%, Language Disorder in 11% and Mood Disorder in 9.4% of patients. In LD NOS subgroup, Language Disorder was present in 28.6%, Developmental Coordination Disorder in 27.5%, ADHD in 25.4%, Anxiety Disorder in 16.4%, Mood Disorder in 2.1% of patients. A statistically significant presence was respectively found for Language and Developmental Coordination Disorder comorbidity in LD NOS and for ADHD, mood and anxiety disorder comorbidity in SLD subgroup.

Conclusions

The different findings emerging in this study suggested to promote further investigations to better define the difference between SLD and LD NOS, in order to improve specific interventions to reduce the long range consequences.

     

Factors associated with anxiety in family caregivers of children with chronic diseases

Background

Currently, information on factors associated with anxiety in family caregivers of children with chronic diseases is unavailable, indicating a significant gap in the literature. Therefore, this study aims to identify the psychosocial and sociodemographic variables associated with anxiety in family caregivers of children with chronic diseases.

Methods

In 2018, a nonprobability sample of 446 family caregivers was recruited at the National Institute of Health in Mexico City. The participants completed a sociodemographic variable questionnaire, clinical questions, and 18 psychosocial assessment scales, including a scale to assess family caregiver anxiety.

Results

Family caregiver anxiety was correlated with almost all psychosocial variables and one out of three clinical variables but with none of the sociodemographic variables. Furthermore, a multiple linear regression model with five psychosocial variables was established to predict family caregiver anxiety.

Conclusions

Some psychosocial variables have effects on caregiver anxiety that are relevant for interventions. Clinical interventions should be implemented based on the psychosocial variables associated with family caregiver anxiety.

     

Caregiver burden in amyotrophic lateral sclerosis is more dependent on patients’ behavioral changes than physical disability: a comparative study

Background

Behavioral changes in patients with amyotrophic lateral sclerosis (ALS) mirror those found in frontotemporal dementia (FTD). Considering the high rate of neuropsychiatric symptoms found in ALS patients, this paper examines whether caregiver burden is associated with behavioral changes over and above the physical disability of patients with ALS, and if the presence of caregivers’ depression, anxiety and stress also impacts on caregiver burden.

Methods

140 caregivers of patients with ALS participated in a postal survey investigating patients’ neuropsychiatric symptoms (Cambridge Behaviour Inventory Revised CBI-R), motor function (Amyotrophic Lateral Sclerosis Functional Rating Scale Revised - ALSFRS-R), caregiver burden (Zarit Burden Interview), and caregiver mood (Depression, Anxiety and Stress Scale- DASS21). Seventy four percent of them were caregivers of patients with limb onset and 25.7% were caregivers of patients with bulbar onset.

Results

Moderate to severe behavioral changes were reported in 10-40% of patients with ALS. The levels of depression, anxiety and stress in the caregivers reached 20%. Burden was high in 48% of the caregivers. The strongest predictor of high caregiver burden was ALS patients’ abnormal behavior rather than physical disability, with an odds ratio of 1.4, followed by caregivers’ stress.

Conclusions

Our study has identified that behavioral changes (e.g. disinhibition, impulsivity) and caregiver stress have greater impact on caregiver burden than level and pattern of physical disability.

     

Gastrointestinal specific anxiety in irritable bowel syndrome: validation of the Japanese version of the visceral sensitivity index for university students

Objective

The visceral sensitivity index (VSI) is a useful self-report measure of the gastrointestinal symptom-specific anxiety (GSA) of patients with irritable bowel syndrome (IBS). Previous research has shown that worsening GSA in IBS patients is related to the severity of GI symptoms, suggesting that GSA is an important endpoint for intervention. However, there is currently no Japanese version of the VSI. We therefore translated the VSI into Japanese (VSI-J) and verified its reliability and validity.

Material and methods

Participants were 349 university students aged 18 and 19 years and recruited from an academic class. We analyzed data from the VSI-J, Anxiety Sensitivity Index (ASI), Hospital Anxiety and Depression scale (HAD), and Irritable Bowel Syndrome Severity Index (IBS-SI). The internal consistency, stability, and factor structure of the VSI-J and its associations with anxiety, depression and severity measures were investigated.

Results

The factor structure of the VSI-J is unidimensional and similar to that of the original VSI (Cronbach’s α?=?0.93). Construct validity was demonstrated by significant correlations with ASI (r?=?0.43, p?<?0.0001), HAD-ANX (r?=?0.19, p?=?0.0003), and IBS-SI scores (r?=?0.45, p?<?0.0001). Furthermore, the VSI-J was a significant predictor of severity scores on the IBS-SI and demonstrated good discriminant (p?<?0.0001) and incremental (p?<?0.0001) validity.

Conclusion

These findings suggest that the VSI-J is a reliable and valid measure of visceral sensitivity.

     

Factors associated with pain level in non-cardiac chest pain patients with comorbid panic disorder

Background

Panic disorder (PD) is highly prevalent in patients with non-cardiac chest pain (NCCP). This study aims to explore the role of psychological factors (PD intensity, anxiety sensitivity, heart-related fear, attention and avoidance) common to NCCP and PD in predicting chest pain levels in patients with both conditions.

Methods

This association was investigated in emergency department patients with NCCP and PD receiving either evidence-based treatment of PD or treatment as usual. Patients were assessed at baseline and 14 weeks later for post-treatment.

Results

Only heart-focused fear and attention for cardiac sensations independently explained a significant portion of the variance in baseline pain (n?=?66). At 3 months follow-up (n?=?53), changes in heart-related fear was the only factor independently associated with changes in chest pain intensity. Even in patients with PD, fear specific to cardiac sensations seems to play a central role in determining NCCP intensity.

Conclusion

These results suggest that the efficacy of intervention for patients with PD and comorbid NCCP could be improved by targeting heart-related fear and attention.

Trial registration

NCT00736346

     

An elevated plus-maze in mixed reality for studying human anxiety-related behavior

Background

A dearth of laboratory tests to study actual human approach-avoidance behavior has complicated translational research on anxiety. The elevated plus-maze (EPM) is the gold standard to assess approach-avoidance behavior in rodents.

Methods

Here, we translated the EPM to humans using mixed reality through a combination of virtual and real-world elements. In two validation studies, we observed participants’ anxiety on a behavioral, physiological, and subjective level.

Results

Participants reported higher anxiety on open arms, avoided open arms, and showed an activation of endogenous stress systems. Participants’ with high anxiety exhibited higher avoidance. Moreover, open arm avoidance was moderately predicted by participants’ acrophobia and sensation seeking, with opposing influences. In a randomized, double blind, placebo controlled experiment, GABAergic stimulation decreased avoidance of open arms while alpha-2-adrenergic antagonism increased avoidance.

Conclusion

These findings demonstrate cross-species validity of open arm avoidance as a translational measure of anxiety. We thus introduce the first ecologically valid assay to track actual human approach-avoidance behavior under laboratory conditions.

     

The association between type D personality,and depression and anxiety ten years after PCI

Objective

There are indications that type D personality and depression are associated in patients treated with percutaneous coronary intervention (PCI). However, at present it is unclear whether this relationship holds in the long term. This study’s aim was to investigate the association between type D personality at 6 months post-PCI (baseline), and depression at 10-year follow-up. A secondary aim was to test the association between type D personality at baseline and anxiety at 10-year follow-up.

Methods

A cohort of surviving consecutive patients (N = 534) who underwent PCI between October 2001 and October 2002. Patients completed the type D personality scale (DS14) measuring type D personality at baseline, and the Hospital Anxiety and Depression Scale (HADS) measuring anxiety and depression at baseline and at 10 years post-PCI.

Results

At baseline, the prevalence of type D personality was 25?% (135/534). Type D personality patients were more often depressed (42?%) than non-type D personality patients (9?%). Response rate of anxiety and depression questionnaires at 10 years was 75?%. At 10-year follow-up, 31?% of type D personality patients were depressed versus 13?% of non-type D personality patients. After adjustments, baseline type D personality remained independently associated with depression at 10 years (OR = 3.69; 95?% CI [1.89–7.19]). Type D showed a similar association with anxiety at 10 years, albeit somewhat lower (OR = 2.72; 95?% CI [1.31–5.63]).

Conclusions

PCI patients with type D personality had a 3.69-fold increased risk for depression and a 2.72-fold increased risk for anxiety at 10 years of follow-up.

     

Amelioration of patients with chronic spontaneous urticaria in treatment with vitamin D supplement

Background

Spontaneous urticaria is a common allergic skin condition affecting 0.5–1% of individuals and may burden on health care expenditure or may be associated with remarkable morbidity.

Aim

In this study, we measured the effect of vitamin D supplementation in patients with a diagnosis of CSU. Furthermore, quality of life and cytokine changes were evaluated.

Methods

The clinical trial was conducted on 20 patients with idiopathic chronic urticaria. Vitamin D was administered orally for 8 weeks and disease activity was measured pre- and post-treatment using USS and DLQI. On the other hand expressions of IL-17, IL-10, Foxp3, and TGF-β by Real-time RT-PCR were assessed.

Results

USS questionnaire showed that severity of idiopathic urticaria after the intervention, which compared with the first day reached a significant 55% reduction. The DLQI quality of life questionnaire 2 months after treatment showed 55% improvement. Along with the significant improvement of clinical symptoms, use of vitamin D increase FOXP3 gene expression and downregulation of IL-10, TGF-B, and FOXP3, IL-17, but these changes were not statistically significant.

Limitation

These might happen due to lack of enrolled population in the investigation.

Conclusion

Vitamin D can be used along with standard medical care and it’s a safe and cost-effective method for the treatment of chronic urticaria with deficiency of vitamin D.

     

Childhood physical abuse in outpatients with psychosomatic symptoms

Background

In Japan and Asia, few studies have been done of physical and sexual abuse. This study was aimed to determine whether a history of childhood physical abuse is associated with anxiety, depression and self-injurious behavior in outpatients with psychosomatic symptoms.

Methods

We divided 564 consecutive new outpatients at the Department of Psychosomatic Medicine of Kyushu University Hospital into two groups: a physically abused group and a non-abused group. Psychological test scores and the prevalence of self-injurious behavior were compared between the two groups.

Results

A history of childhood physical abuse was reported by patients with depressive disorders(12.7%), anxiety disorders(16.7%), eating disorders (16.3%), pain disorders (10.8%), irritable bowel syndrome (12.5%), and functional dyspepsia(7.5%). In both the patients with depressive disorders and those with anxiety disorders, STAI-I (state anxiety) and STAI-II (trait anxiety) were higher in the abused group than in the non-abused group (p < 0.05).In the patients with depressive disorders, the abused group was younger than the non-abused group (p < 0.05). The prevalence of self-injurious behavior of the patients with depressive disorders, anxiety disorders and pain disorders was higher in the abused groups than in the non-abused groups (p < 0.005).

Conclusion

A history of childhood physical abuse is associated with psychological distress such as anxiety, depression and self-injurious behavior in outpatients with psychosomatic symptoms. It is important for physicians to consider the history of abuse in the primary care of these patients.

     

Hypocapnia is a biological marker for orthostatic intolerance in some patients with chronic fatigue syndrome

Context

Patients with chronic fatigue syndrome and those with orthostatic intolerance share many symptoms, yet questions exist as to whether CFS patients have physiological evidence of orthostatic intolerance.

Objective

To determine if some CFS patients have increased rates of orthostatic hypotension, hypertension, tachycardia, or hypocapnia relative to age-matched controls.

Design

Assess blood pressure, heart rate, respiratory rate, end tidal CO2 and visual analog scales for orthostatic symptoms when supine and when standing for 8 minutes without moving legs.

Setting

Referral practice and research center.

Participants

60 women and 15 men with CFS and 36 women and 4 men serving as age matched controls with analyses confined to 62 patients and 35 controls showing either normal orthostatic testing or a physiological abnormal test.

Main outcome measures

Orthostatic tachycardia; orthostatic hypotension; orthostatic hypertension; orthostatic hypocapnia or combinations thereof.

Results

CFS patients had higher rates of abnormal tests than controls (53% vs 20%, p < .002), but rates of orthostatic tachycardia, orthostatic hypotension, and orthostatic hypertension did not differ significantly between patients and controls (11.3% vs 5.7%, 6.5% vs 2.9%, 19.4% vs 11.4%, respectively). In contrast, rates of orthostatic hypocapnia were significantly higher in CFS than in controls (20.6% vs 2.9%, p < .02). This CFS group reported significantly more feelings of illness and shortness of breath than either controls or CFS patients with normal physiological tests.

Conclusion

A substantial number of CFS patients have orthostatic intolerance in the form of orthostatic hypocapnia. This allows subgrouping of patients with CFS and thus reduces patient pool heterogeneity engendered by use of a clinical case definition.

     

Combination of anxiety and depression is associated with an increased headache frequency in migraineurs: a population-based study

Background

Although anxiety and depression have been classified as distinct traits of affective disorders, previous studies have reported their co-occurrence in subjects with migraine. However, few reports are available on the clinical implications of this comorbidity. This study is to assess the comorbidity of anxiety and depression in subjects with migraine and its clinical implications in a population-based sample from Korea.

Methods

We selected Korean subjects aged 19–69 years by the stratified random sampling method, and evaluated them using a semi-structured interview, designed to identify headache type, anxiety, and depression. We used Goldberg Anxiety Scale questions and Patient Health Questionnnaire-9 for the diagnosis of anxiety and depression, respectively.

Results

Of the 2,762 participants who completed the interview, 147 subjects (5.4%) were classified as having a migraine during the previous year. Among these 147 subjects, 17 (11.6%) had anxiety and depression, 28 (19.0%) had anxiety alone, 9 (6.1%) had depression alone, and 93 (63.3%) had neither anxiety nor depression. Headache frequency per month was remarkably higher in subjects having migraine with anxiety and depression (median [25–75 percentile values], 8.0 [2.5–21.0]) than in those having migraine with anxiety alone (2.0 [1.0–5.0], p?=?0.003), migraine with depression alone (1.0 [0.3–4.0], p?=?0.001), and migraine without anxiety or depression (1.0 [0.3–3.0], p?<?0.001). The migraine with anxiety alone (7.0 [6.0–8.0], p?=?0.011) group and migraine with anxiety and depression (7.0 [5.0–9.0], p?=?0.018) group showed higher Visual Analogue Scale scores for pain intensity compare to migraine without anxiety or depression (6.0 [5.0-7.0]) group.

Conclusions

Approximately 1/3 of migraineurs with anxiety had depression and 2/3 of migraineurs with depression had anxiety. Combination of anxiety and depression was associated with an increased headache frequency. Anxiety was associated with exacerbation of headache intensity.

     

A lost opportunity for science: journals promote data sharing in metabolomics but do not enforce it

Introduction

Data sharing is being increasingly required by journals and has been heralded as a solution to the ‘replication crisis’.

Objectives

(i) Review data sharing policies of journals publishing the most metabolomics papers associated with open data and (ii) compare these journals’ policies to those that publish the most metabolomics papers.

Methods

A PubMed search was used to identify metabolomics papers. Metabolomics data repositories were manually searched for linked publications.

Results

Journals that support data sharing are not necessarily those with the most papers associated to open metabolomics data.

Conclusion

Further efforts are required to improve data sharing in metabolomics.

     

Systematic re-evaluation of intraoperative motor-evoked potential suppression in scoliosis surgery

Background

Motor- (MEP) and somatosensory-evoked potentials (SSEP) are susceptible to the effects of intraoperative environmental factors.

Methods

Over a 5-year period, 250 patients with adolescent idiopathic scoliosis (AIS) who underwent corrective surgery with IOM were retrospectively analyzed for MEP suppression (MEPS).

Results

Our results show that four distinct groups of MEPS were encountered over the study period. All 12 patients did not sustain any neurological deficits postoperatively. However, comparison of groups 1 and 2 suggests that neither the duration of anesthesia nor speed of surgical or anesthetic intervention were associated with recovery to a level beyond the criteria for MEPS. For group 3, spontaneous MEPS recovery despite the lack of surgical intervention suggests that anesthetic intervention may play a role in this process. However, spontaneous MEPS recovery was also seen in group 4, suggesting that in certain circumstances, both surgical and anesthetic intervention was not required. In addition, neither the duration of time to the first surgical manoeuver nor the duration of surgical manoeuver to MEPS were related to recovery of MEPS. None of the patients had suppression of SSEPs intraoperatively.

Conclusion

This study suggests that in susceptible individuals, MEPS may rarely occur unpredictably, independent of surgical or anesthetic intervention. However, our findings favor anesthetic before surgical intervention as a proposed protocol. Early recognition of MEPS is important to prevent false positives in the course of IOM for spinal surgery.

     

Predictors of successful long-term weight loss maintenance: a two-year follow-up

Background

Weight regain is a common problem following weight loss intervention, with most people who seek treatment for obesity able to lose weight, but few able to sustain the changes in behavior required to prevent subsequent weight regain. The identification of factors that predict which patients will successfully maintain weight loss or who are at risk of weight regain after weight loss intervention is necessary to improve the current weight maintenance strategies. The aim of the present study is identify factors associated with successful weight loss maintenance by women with overweight or obesity who completed group cognitive behavioral treatment (CBT) for weight loss.

Methods

Ninety women with overweight or obesity completed a 7-month weight loss intervention. The data of 86 who completed follow-up surveys 12 and 24 months after the end of the treatment was analyzed. Depression, anxiety, binge eating, food addiction, and eating behaviors were assessed before and after the weight loss intervention. Participants who lost at least 10% of their initial weight during the weight loss intervention and had maintained the loss at the month 24 follow-up were defined as successful.

Results

The intervention was successful for 27 participants (31.3%) and unsuccessful for 59 (68.6%). Multiple logistic regression analysis extracted larger weight reduction during the weight loss intervention, a lower disinhibition score, and a low food addiction score at the end of the weight loss intervention as associated with successful weight loss maintenance.

Conclusion

The results suggest that larger weight reduction during the weight loss intervention and lower levels of disinhibition and food addiction at the end of the weight loss intervention predicted successful weight loss maintenance.

Trial registration

Trial registry name: Development and validation of effective treatments of weight loss and weight-loss maintenance using cognitive behavioral therapy for obese patients.Registration ID: UMIN000006803Registered 1 January 2012.URL: https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000008052

     

Optimization of fecal sample preparation for untargeted LC-HRMS based metabolomics

Introduction

Collecting feces is easy. It offers direct outcome to endogenous and microbial metabolites.

Objectives

In a context of lack of consensus about fecal sample preparation, especially in animal species, we developed a robust protocol allowing untargeted LC-HRMS fingerprinting.

Methods

The conditions of extraction (quantity, preparation, solvents, dilutions) were investigated in bovine feces.

Results

A rapid and simple protocol involving feces extraction with methanol (1/3, M/V) followed by centrifugation and a step filtration (10 kDa) was developed.

Conclusion

The workflow generated repeatable and informative fingerprints for robust metabolome characterization.

     

Analysis of influencing factor of coexisting prediabetes and prehypertension in adult residents of Jilin Province

Background

To explore the risk factors of coexisting prediabetes and prehypertension, to provide theoretical basis for early intervention.

Methods

A multi-stage stratified random cluster sampling method was used to randomly select adult residents from Jilin Province in 2013 for questionnaire surveys, physical examinations, and laboratory tests.

Results

The prevalence of coexisting prediabetes and prehypertension in Jilin Province was 11.3%. The binary Logistic regression results showed that age, sex, education, triglyceride (TG), BMI, waist circumference and alcohol consumption were the effects of factor coexisting prediabetes and prehypertension.

Conclusion

It is important to pay attention to the early stage of hypertension and diabetes, control the transition from prehypertension and prediabetes to hypertension and diabetes, and improve the health of residents.

     

Relationship between breast arterial calcification on mammography with coronary CT angiography findings

Background

Breast arterial calcification is a frequently benign finding on mammography that usually is not reported. An increasing attention has been formed to determine the association between breast arterial calcification (BAC) and Coronary artery disease. In the current study we have aimed to evaluate the relationship between BAC on mammography with coronary CT angiography findings.

Methods

The case control study was carried out on 60 women; 30 CAD and 30 healthy subjects as control, admitted to Golestan hospital radiology department. The mammography was performed in two views; Craniocaudal (CC) view and mediolateral oblique (MLO) and BAC was graded based on the severity and extent of calcifications. Coronary Arterial Calcification (CAC) were scored by Agatston criteria.

Results

Overly, 36 patients (60%) were positive for BAC. Twenty six out of them (72%) were CAD. There was a positive significant correlation between BAC and CAD. The sensitivity and specificity of BAC for CAD were 69% and 47%, respectively. Moreover, the severe BAC scores were significantly higher in CAD patients than non-CAD.

Conclusion

Our findings in line with several previous studies indicated the positive significant association between BAC and CAD occurrence. While the sensitivity and specificity of BAC in diagnosis of CAD is low, suggested the using of BAC just as a CAD risk factor. The relatively low sample size is the major limitation of the study.

     

Dizziness in peri- and postmenopausal women is associated with anxiety: a cross-sectional study

Background

Although dizziness is one of the most common symptoms of menopause, the underlying mechanism is not precisely known. Therefore, this study aimed to investigate the prevalence of, and the factors associated with, dizziness in peri- and postmenopausal women.

Methods

We conducted a cross-sectional study in which we analyzed the first-visit records of 471 Japanese women aged 40 to 65?years who enrolled in a health and nutrition education program at a menopause clinic. The prevalence of dizziness was estimated according to the participants’ responses to the Menopausal Health-Related Quality of Life Questionnaire. The background characteristics of age, menopause status, body composition, cardiovascular parameters, basal metabolism, and physical fitness; other menopausal symptoms, including vasomotor, insomnia, depression, and anxiety symptoms; and lifestyle characteristics were assessed for their associations with dizziness.

Results

The percentage of women who suffered from dizziness once a week or more frequently was 35.7%. Compared to the women without dizziness, those with the symptom were younger; had a higher body weight, body mass index, body fat percentage, muscle mass, and waist-to-hip ratio; had higher systolic pressure; were slower in reaction time; had higher physical and psychological symptom scores of menopause; exercised less regularly; and consumed less alcohol. A multivariate logistic regression analysis revealed that the anxiety symptom, which was evaluated by the Hospital Anxiety and Depression Scale, was the sole factor that was independently associated with dizziness (adjusted odds ratio 1.14; 95% confidence interval 1.08–1.20).

Conclusions

Dizziness is highly prevalent in Japanese peri- and postmenopausal women and it is associated with anxiety. The treatment of anxiety in this population might improve the symptom.

     

The Association Between Depression,Suicidal Ideation and Psychological Strains in College Students: A Cross-National Study

Objective

This study examined the differences of psychological strains between Chinese and American college students and discussed how strains may influence individuals’ suicidal ideation and depression.

Participants/methods

A total of 539 college students (298 from China and 241 from the U.S.) were recruited in March 2016 to complete the survey study. Multiple linear regressions were used in data analysis.

Results

Students in America had higher scores on depression and stress than students in China, while students in China rated higher on suicidal ideation than students in America. In contrast of students in America facing more coping strains, students in China were confronting more value strains in their life.

Conclusion

The cross-cultural variations in the effect of psychological strains have been substantiated in current study, indicating that understanding the psychological strains in different cultural contexts is necessary for the early intervention and prevention in college aged populations.

     

Factor XIII Val34Leu polymorphism and risk of recurrent pregnancy loss in Iranian population: a case control study

BACKGROUND

Recurrent pregnancy loss (RPL) is a heterogeneous condition and thrombophilias have been considered as a probable cause.

OBJECTIVE

The aim of this study was to investigate the prevalence of the coagulation factor XIII Val34Leu polymorphism among women with unexplained RPL.

METHODS

A total of 140 women with a history of unexplained RPL and 100 age-matched healthy fertile women were recruited. The presence of FXIII Val34Leu polymorphism among the cases and controls was investigated using PCR-RFLP method.

RESULTS

Genotype analyses of the subjects revealed that the patients had a significantly higher prevalence of V/L and L/L than the controls (P<0.05): 33.5% vs. 15%, and 9.2% vs. 2%, respectively.

CONCLUSION

These results indicate a significant association between FXIII Val34Leu polymorphism and unexplained RPL in the Iranian patient.