Current status of the use of single-nucleotide polymorphisms in forensic practices.

Forensic geneticists often use short tandem repeats (STRs) to solve cases. However, STRs can be insufficient when DNA samples are degraded due to environmental exposure and mass disasters, alleged and real relatives are genetically related in paternity or kinship analyses, or a suspect is lacking. In such cases, single-nucleotide polymorphisms (SNPs) can provide valuable information and thus should be seriously considered as a tool to help resolve challenging cases. In this review, the current status of SNP analyses in forensic applications and the comparative advantages and disadvantages of SNPs with other biomarkers are discussed.

Psychopathy and facial emotion recognition ability in patients with bipolar affective disorder with or without delinquent behaviors.

BACKGROUND: It is well known that patients with bipolar disorder are more prone to violence and have more criminal behaviors than general population. A strong relationship between criminal behavior and inability to empathize and imperceptions to other person's feelings and facial expressions increases the risk of delinquent behaviors. In this study, we aimed to investigate the deficits of facial emotion recognition ability in euthymic bipolar patients who committed an offense and compare with non-delinquent euthymic patients with bipolar disorder. METHOD: Fifty-five euthymic patients with delinquent behaviors and 54 non-delinquent euthymic bipolar patients as a control group were included in the study. Ekman's Facial Emotion Recognition Test, sociodemographic data, Hare Psychopathy Checklist, Hamilton Depression Rating Scale and Young Mania Rating Scale were applied to both groups. RESULTS: There were no significant differences between case and control groups in the meaning of average age, gender, level of education, mean age onset of disease and suicide attempt (p>0.05). The three types of most committed delinquent behaviors in patients with euthymic bipolar disorder were as follows: injury (30.8%), threat or insult (20%) and homicide (12.7%). The best accurate percentage of identified facial emotion was "happy" (>99%, for both) while the worst misidentified facial emotion was "fear" in both groups (<50%, for both). The total accuracy rate of recognition toward facial emotions was significantly impaired in patients with delinquent behaviors than non-delinquent ones (p<0.05). The accuracy rate of recognizing the fear expressions was significantly worse in the case group than in the control group (p<0.05). In addition, it tended to be worse toward angry facial expressions in criminal euthymic bipolar patients. The response times toward happy, fear, disgusted and angry expressions had been significantly longer in the case group than in the control group (p<0.05). CONCLUSION: This study is the first, searching the ability of facial emotion recognition in euthymic patients with bipolar disorder who had delinquent behaviors. We have shown that patients with bipolar disorder who had delinquent behaviors may have some social interaction problems i.e., misrecognizing fearful and modestly anger facial emotions and need some more time to response facial emotions even in remission.

Determination of standard number, size and weight of mediastinal lymph nodes in postmortem examinations: reflection on lung cancer surgery.

BACKGROUND: Mediastinal lymph node dissection is an essential component of lung cancer surgery. Literature lacks established information regarding the number and size of the healthy lymph nodes. In this postmortem autopsy study, we aim to define the number, size and weight of the lymph nodes in each mediastinal lymph node station. To implement the data for the clinical practice, we analyzed the possible number of nodes to be dissected in a systematic mediastinal lymph node dissection from the right and left sides during lung cancer surgery. METHODS: Sixty-two samples obtained from cadavers who did not die from chest malignancies, extrathoracic malignancies, any kind of infections or previous hospitalization before the death were included to the study. The locations of the nodes were recorded according to the American Thoracic Society Mediastinal Lymph Node Map. The number, size and weight of the nodes were determined at each station. RESULTS: Median age of the cadavers was 39 years. Primary causes of death were asphyxia in 10 (16.1%) subjects, trauma in 29 (46.8%) subjects, cardiovascular problems in 10 (16.1%) subjects, and undetermined in 13 (21%) subjects. The median number of lymph nodes resected from each patient was 23 (range: 11-54). The right sided paratracheal lymph nodes (Station 2R and 4R) were more frequent, heavier and longer than left sided lymph nodes (Station 2L and 4L) at the paratrecheal region. Right sided inferior mediastinal lymph nodes were heavier and longer than the left ones; however, their availability was more often on the left. CONCLUSIONS: The properties of mediastinal lymph nodes at particular stations are different for number, size and weight. Station 4R and 7 have the highest number of nodes followed by stations 5 and 6. We recommend removing the lymph nodes of these stations completely in lung cancer patients to rule out the possibility of micrometastatic disease. Diameter of normal lymph node may be 1 cm for the stations other than 4R and 7, but the definition of normal diameter of a lymph node at the stations 4R and 7 may be changed as 1,5 cm and 2,0 cm, respectively. Weight of the nodes may be a new subject to study and may be defined as a new modality to define a staging to be more accurate and the issue needs further investigations.

Effect of partial, distal epicondylectomy on reduction of ulnar nerve strain: a cadaver study.

PURPOSE: To compare the decrease in ulnar nerve strains using a modification of medial epicondylectomy by removing the distal half of the medial epicondyle with in situ decompression and partial medial epicondylectomy. METHODS: Using 20 elbows of 10 fresh human cadavers, we measured the strain on the ulnar nerve using a microstrain gauge before and after in situ decompression. Then, we repeated the measurements after partial medial epicondylectomy on left elbows, and after distal medial epicondylectomy on right elbows. We compared the mean strain values with 2-way analysis of variance. RESULTS: The decrease in mean ulnar nerve strain with in situ decompression from 5.4% to 5.2% on the right side and 5.4% to 5.0% on the left was not statistically significant. The decrease to 2.9% on the left elbows after partial and to 1.9% on the right elbows after distal medial epicondylectomy was statistically significant. In addition, the remaining ulnar nerve strain after distal medial epicondylectomy was significantly less compared with that after partial medial epicondylectomy. We observed nerve subluxation only with partial medial epicondylectomy. CONCLUSIONS: In situ decompression alone does not change ulnar nerve strains. The significant change in ulnar nerve strain with partial or distal medial epicondylectomy underlines the role of medial epicondyle on stretching of the ulnar nerve. Excision of the distal half of the medial epicondyle sets the contact point of the nerve with the bone proximally and decreases the strain on ulnar nerve more effectively than partial epicondylectomy. However, its efficacy and complications need to be studied clinically. CLINICAL RELEVANCE: The results of the present cadaveric study suggest that excision of the distal half of the medial epicondyle in cubital tunnel syndrome may decrease ulnar nerve strain effectively. The clinical effect of decrease in nerve strain and the indications for the procedure need to be investigated.

Horizontal suture placement influences meniscal repair fixation strength.

PURPOSE: This in vitro biomechanical study investigated the influence of horizontal suture placement distance from the medial meniscal lesion repair site on fixation characteristics during submaximal cyclic and load to failure test conditions. METHODS: Eighteen cadaveric (20-45 years of age) medial menisci with intact joint capsules were harvested within 24-48 h after death and divided into two groups of 9 specimens each for biomechanical testing. A 2.0-cm-long antero-posterior vertical longitudinal lesion was created with a #15 scalpel 2.0-3.0 mm from the outer edge of each meniscus. Menisci were repaired using #2-0 suture material with two horizontal suture loops placed either 1.0 mm (Group 1) or 3.0 mm (Group 2) from the lesion site. Following repair, the lesion was extended completely through the meniscal horns so that no tissue secured the repair, only the two horizontal suture loops representing a "worst-case" testing scenario. Following repair, specimens were placed in a servo hydraulic device using a pair of 1.2-mm-diameter steel wire loops and underwent submaximal cyclic loading between 5 and 50 N (1 Hz) for 500 cycles prior to load to failure testing (5 mm/min crosshead speed, 20 Hz data collection). An alpha level of P < 0.05 was selected to indicate statistical significance. RESULTS: Five of nine (55.6 %) Group 1 specimens did not complete submaximal cyclic testing. All Group 2 specimens completed submaximal cyclic testing (Fisher's exact test P = 0.029). Statistically significant mean group differences were not observed for displacement during submaximal cyclic loading (Group 1 = 5.0 ± 1.5 mm and Group 2 = 5.7 ± 1.6 mm) or for construct stiffness during load to failure testing (Group 1 = 50.1 ± 6.3 N/mm and Group 2 = 52.6 ± 11.9 N/mm). Group 2 displayed greater mean load at failure (112.1 ± 40.8 N vs. 72.7 ± 11.2 N, P = 0.02) and mean displacement at failure (11.1 ± 2.2 mm vs. 7.6 ± 1.4 mm, P = 0.03) than Group 1. CONCLUSIONS: Horizontal sutures placed slightly farther away from the meniscus lesion displayed superior repair fixation than sutures placed closer to the lesion. The superior biomechanical meniscal repair fixation provided by capturing greater tissue volume may enable safe earlier participation in functional exercise activities. Studies are needed to verify these findings in vivo.

Determining the most suitable costal cartilage level for rhinoplasty: an experimental study.

OBJECTIVE: The aim of this study was to compare the biomechanical properties of septal cartilage (SC) and costal cartilage (CC) grafts harvested from different ribs and to find at which level CC has characteristics closest to SC. STUDY DESIGN: Experimental cadaver study. SETTING: Istanbul Training and Research Hospital. MATERIAL AND METHOD: Cartilage grafts were harvested from the 6th, 7th, and 8th ribs and the SC of 10 fresh cadavers. Shaped cartilage grafts were subjected to a bending test. Results were measured, and the force-deflection curve was plotted. Flexural strength (σ(f)) and flexural modulus of elasticity (E(f)) were determined. Fractured surfaces were evaluated by scanning electron microscopy (SEM). RESULTS: According to F(max), it was determined that ribs 6, 7, and 8 have significantly more durability compared with the SC (Ps = .030, .004, and .001). With regard to deflection, there was no significant difference between the SC and the 6th and 7th ribs and between the 6th and 7th ribs (Ps = 1.000, .088, and .306), while a significant difference was found between the SC and the 8th rib (P = .001). According to σ(f), no differences were seen between the 6th and 7th rib (P = .782), while difference was detected between the 6th and 8th and the 7th and 8th ribs (p = .001). Similar trends were established in E(f) values as in σ(f.) These results were confirmed by SEM images. CONCLUSION: The 7th CC can be used as autograft because it shows similar properties to SC. However, the 6th CC is preferred if more flexibility is desired, and the 8th CC is preferred where more strength is needed.

Fatal cranial shot by blank cartridge gun: two suicide cases.

Blank firing pistols are generally considered to be harmless and these guns are not accepted as being firearms in most countries. Due to lack of legal regulations these guns are easily purchased by anyone aged over 18 years. Reports of serious injuries and even fatalities due to these guns are increasing in the literature. These guns when modified or even unmodified can cause serious and potentially fatal injuries. Without doing any changes to the barrel, using blank or tear gas cartridges, firing at contact range can cause penetration of gas into the body including bone originated from gun powder. We report two suicide cases shooting themselves at temporal region with a blank cartridge gun at contact range. There was no foreign body on radiological examination and there was no trajectory of a bullet inside the brain. In both cases the wound was at the right temporal region and there was defect at temporal bone. There was circular soot around this bone defect. The injury of the brain tissue was localized at the level of the defect but there was widespread subarachnoidal bleeding. We discussed the potential danger of these guns and stressed the need of legal regulations concerning these guns.