Serotonin 5-HTTLPR Genotype Modulates Reactive Visual Scanning of Social and Non-social Affective Stimuli in Young Children

Previous studies have documented the 5-HTTLPR polymorphisms as genetic variants that are involved in serotonin availability and also associated with emotion regulation and facial emotion processing. In particular, neuroimaging and behavioral studies of healthy populations have produced evidence to suggest that carriers of the Short allele exhibit heightened neurophysiological and behavioral reactivity when processing aversive stimuli, particularly in brain regions involved in fear. However, an additional distinction has emerged in the field, which highlights particular types of fearful information, i.e., aversive information which involves a social component versus non-social aversive stimuli. Although processing of each of these stimulus types (social and non-social) is believed to involve a subcortical neural system which includes the amygdala, evidence also suggests that the amygdala itself may be particularly responsive to socially significant environmental information, potentially due to the critical relevance of social information for humans. Examining individual differences in neurotransmitter systems which operate within this subcortical network, and in particular the serotonin system, may be critically informative for furthering our understanding of the neurobiological mechanisms underlying responses to emotional and affective stimuli. In the present study we examine visual scanning patterns in response to both aversive and positive images of a social or non-social nature in relation to 5-HTTLPR genotypes, in 49 children aged 4–7 years. Results indicate that children with at least one Short 5-HTTLPR allele spent less time fixating the threat-related non-social stimuli, compared with participants with two copies of the Long allele. Interestingly, a separate set of analyses suggests that carriers of two copies of the short 5-HTTLPR allele also spent less time fixating both the negative and positive non-social stimuli. Together, these findings support the hypothesis that genetically mediated differences in serotonin availability mediate behavioral responses to different types of emotional stimuli in young children.

BDNF Val(66)Met and 5-HTTLPR Genotype are Each Associated with Visual Scanning Patterns of Faces in Young Children

Previous studies have documented both neuroplasticity-related BDNF Val(66)Met and emotion regulation-related 5-HTTLPR polymorphisms as genetic variants that contribute to the processing of emotions from faces. More specifically, research has shown the BDNF Met allele and the 5-HTTLPR Short allele to be associated with mechanisms of negative affectivity that relate to susceptibility for psychopathology. We examined visual scanning pathways in response to angry, happy, and neutral faces in relation to BDNF Val(66)Met and 5-HTTLPR genotyping in 49 children aged 4-7 years. Analyses revealed that variations in the visual processing of facial expressions of anger interacted with BDNF Val(66)Met genotype, such that children who carried at least one low neuroplasticity Met allele exhibited a vigilance-avoidance pattern of visual scanning compared to homozygotes for the high neuroplasticity Val allele. In a separate investigation of eye gaze towards the eye versus mouth regions of neutral faces, we observed that short allele 5-HTTLPR carriers exhibited reduced looking at the eye region compared with those with the higher serotonin uptake Long allele. Together, these findings suggest that genetic mechanisms early in life may influence the establishment of patterns of visual scanning of environmental stressors, which in conjunction with other factors such as negative life events, may lead to psychological difficulties and disorders in the later adolescent and adult years.

A comprehensive next generation sequencing-based genetic testing strategy to improve diagnosis of inherited pheochromocytoma and paraganglioma

CONTEXT

Pheochromocytomas and paragangliomas are notable for a high frequency of inherited cases, many of which present as apparently sporadic tumors.

OBJECTIVE

The objective of this study was to establish a comprehensive next generation sequencing (NGS)-based strategy for the diagnosis of patients with pheochromocytoma and paraganglioma by testing simultaneously for mutations in MAX, RET, SDHA, SDHB, SDHC, SDHD, SDHAF2, TMEM127, and VHL.

DESIGN

After the methodology for the assay was designed and established, it was validated on DNA samples with known genotype and then patients were studied prospectively.

SETTING

The study was performed in a diagnostic genetics laboratory.

PATIENTS

DNA samples from 205 individuals affected with adrenal or extraadrenal pheochromocytoma/head and neck paraganglioma (PPGL/HNPGL) were analyzed. A proof-of-principle study was performed using 85 samples known to contain a variant in 1 or more of the genes to be tested, followed by prospective analysis of an additional 120 samples.

MAIN OUTCOME MEASURES

We assessed the ability to use an NGS-based method to perform comprehensive analysis of genes implicated in inherited PPGL/HNPGL.

RESULTS

The proof-of-principle study showed that the NGS assay and analysis gave a sensitivity of 98.7%. A pathogenic mutation was identified in 16.6% of the prospective analysis cohort of 120 patients.

CONCLUSIONS

A comprehensive NGS-based strategy for the analysis of genes associated with predisposition to PPGL and HNPGL was established, validated, and introduced into diagnostic service. The new assay provides simultaneous analysis of 9 genes and allows more rapid and cost-effective mutation detection than the previously used conventional Sanger sequencing-based methodology.

Fructose- and sorbitol-reduced diet improves mood and gastrointestinal disturbances in fructose malabsorbers

BACKGROUND

Fructose malabsorption is characterized by the inability to absorb fructose efficiently. As a consequence fructose reaches the colon where it is broken down by bacteria to short fatty acids, CO2 and H2. Bloating, cramps, osmotic diarrhea and other symptoms of irritable bowel syndrome are the consequences and can be seen in about 50% of fructose malabsorbers. We have previously shown that fructose malabsorption is associated with early signs of mental depression and low serum tryptophan concentrations. It was therefore of interest whether a fructose-reduced diet could not only improve gastrointestinal complaints but also depressive signs seen in fructose malabsorbers.

METHODS

Fifty-three adults (12 males, 41 females), who were identified as fructose malabsorbers according to their breath-H2 concentrations, filled out a Beck's depression inventory-questionnaire, and a questionnaire with arbitrary scales for measurement of meteorism, stool frequency and quality of life for a 4-week period before dietary intervention and 4 weeks after dietary change as for fructose- and sorbitol-reduced diet.

RESULTS

Depression scores were reduced by 65.2% after 4 weeks of diet (P < 0.0001), and there was a significant reduction of meteorism (P < 0.0001) and stool frequency (P < 0.01). Improvement of signs of depression and of meteorism was more pronounced in females than in males.

CONCLUSION

Fructose- and sorbitol-reduced diet in subjects with fructose malabsorption does not only reduce gastrointestinal symptoms but also improves mood and early signs of depression.

Hypothermia-induced coagulopathy during hemorrhagic shock

A porcine model of hemorrhagic shock was used to study the effect of hypothermia on hemodynamic, metabolic, and coagulation parameters. The model was designed to simulate the events of severe blunt injury with hemorrhage occurring initially, to a systolic blood pressure of 30 mm Hg, followed by simultaneous hemorrhage and crystalloid volume replacement, followed by cessation of hemorrhage and blood replacement. Half of the animals were rendered hypothermic by external application of ice, and half remained normothermic. There was seven pigs in each group. Two deaths occurred in each during the hemorrhage phase. The hypothermic pigs demonstrated larger reduction in cardiac output than normothermic pigs. Volume replacement in the normothermic group restored cardiac output to baseline values. In the hypothermic group, cardiac output remained depressed despite volume replacement. Prothrombin times and partial thromboplastin times showed significantly more prolongation in the hypothermic group. Furthermore, this was not corrected by replacement of shed blood in the hypothermic group, as was seen in the normothermic group. We conclude that when shock and hypothermia occur together, their deleterious effect on hemodynamic and coagulation parameters are additive. The effects of hypothermia persist despite the arrest of hemorrhage and volume replacement. Thus, it is necessary to aggressively address both shock and hypothermia when they occur simultaneously.

Tension pneumopericardium during laparoscopy for trauma

A case involving a patient with multiple stab wounds to the thoracoabdomen is reviewed. Laparoscopy was employed to determine peritoneal penetration. Hemodynamic collapse occurred secondary to tension pneumopericardium, which resulted from a 15 mm Hg pneumoperitoneum. The relevant literature is reviewed.

Self-inflicted shotgun injuries to the face: a case report

Shotgun injuries to the face are difficult to care for due to the often massive tissue and bone destruction and the complications that can accompany these injuries. Psychological responses from the family, significant other, and nursing staff in dealing with disfiguring and sometimes fatal injuries are additional challenges that nurses will face.

Nonoperative management of adult blunt splenic trauma: a 15-year experience

From January 1989 to December 1993, 40 consecutive adult patients with ruptured spleen from blunt trauma were examined. Fourteen patients (35%) were taken to the operating room initially because of hemodynamic instability and generalized peritoneal signs. Twenty-six patients (65%) were hemodynamically stabilized at admission and treated by nonoperative management, which included strict bed rest, intensive care unit monitoring, frequent physical examinations, and serial hematocrits. Four patients failed nonsurgical management and required a splenectomy, three because of clinical deterioration within 1 to 3 days of admission; the fourth patient had recurrent bleeding 7 days after injury. The patients in the operative group had a greater severity of injury with a mean injury severity score of 26.6, four deaths, and mean transfusion requirements of 3.7 to 4.0 units of blood, compared to a mean injury severity score of 14.6, one late death from cardiac causes, and average blood requirement of 0.4 to 0.7 units. Splenic injury grading averaged 3.2 in the surgical group (grade 1, one patient; grade 2, four patients; grade 3, eight patients; grade 4, no patients; and grade 5, one patient) and differed significantly from that of the nonoperative group (mean = 2.4; grade 1, 12 patients; grade 2, seven patients; grade 3, six patients; grade 4, two patients; and grade 5, no patients). Recent ultrasound analysis of select grades I to IV has shown excellent resolution or repair of these injuries. This report extends our series from 1978 to 1993 and includes 144 adult patients sustaining blunt splenic ruptures. Seventy-nine (55%) of these patients were treated nonsurgically. Seven patients (of 80) failed nonoperative management and required interval laparotomy, representing a 91 per cent success rate. Follow-up on more than 90 per cent of the patients has shown no sequelae from their splenic injuries. We conclude that adult patients with splenic injuries from blunt trauma who are hemodynamically stable and are without abdominal findings requiring celiotomy can be safely managed by a nonoperative approach.