Mercury and Autism Spectrum Disorder: Exploring the Link through Comprehensive Review and Meta-Analysis

Mercury (Hg) is a non-essential trace metal with unique neurochemical properties and harmful effects on the central nervous system. In this study, we present a comprehensive review and meta-analysis of peer-reviewed research encompassing five crucial clinical matrices: hair, whole blood, plasma, red blood cells (RBCs), and urine. We assess the disparities in Hg levels between gender- and age-matched neurotypical children (controls) and children diagnosed with autism spectrum disorder (ASD) (cases). After applying rigorous selection criteria, we incorporated a total of 60 case-control studies into our meta-analysis. These studies comprised 25 investigations of Hg levels in hair (controls/cases: 1134/1361), 15 in whole blood (controls/cases: 1019/1345), 6 in plasma (controls/cases: 224/263), 5 in RBCs (controls/cases: 215/293), and 9 in urine (controls/cases: 399/623). This meta-analysis did not include the data of ASD children who received chelation therapy. Our meta-analysis revealed no statistically significant differences in Hg levels in hair and urine between ASD cases and controls. In whole blood, plasma, and RBCs, Hg levels were significantly higher in ASD cases compared to their neurotypical counterparts. This indicates that ASD children could exhibit reduced detoxification capacity for Hg and impaired mechanisms for Hg excretion from their bodies. This underscores the detrimental role of Hg in ASD and underscores the critical importance of monitoring Hg levels in ASD children, particularly in early childhood. These findings emphasize the pressing need for global initiatives aimed at minimizing Hg exposure, thus highlighting the critical intersection of human-environment interaction and neurodevelopment health.

Does Lead Have a Connection to Autism? A Systematic Review and Meta-Analysis

Environmental pollutants, particularly toxic trace metals with neurotoxic potential, have been related to the genesis of autism. One of these metals that stands out, in particular, is lead (Pb). We conducted an in-depth systematic review and meta-analysis of peer-reviewed studies on Pb levels in biological materials retrieved from autistic children (cases) and neurotypical children (controls) in this work. A systematic review was conducted after the careful selection of published studies according to established criteria to gain a broad insight into the higher or lower levels of Pb in the biological materials of cases and controls, and the findings were then strengthened by a meta-analysis. The meta-analysis included 17 studies (hair), 13 studies (whole blood), and 8 studies (urine). The overall number of controls/cases was 869/915 (hair), 670/755 (whole blood), and 344/373 (urine). This meta-analysis showed significantly higher Pb levels in all three types of biological material in cases than in controls, suggesting a higher body Pb burden in autistic children. Thus, environmental Pb exposure could be related to the genesis of autism. Since no level of Pb can be considered safe, the data from this study undoubtedly point to the importance of regularly monitoring Pb levels in autistic children.

Climate Variables Related to the Incidence of Human Leishmaniosis in Montenegro in Southeastern Europe during Seven Decades (1945-2014)

Leishmaniosis (or leishmaniasis) is a neglected parasitosis most commonly transmitted by the sandfly bite. Changes in temperature, precipitation, and humidity can greatly affect the vectors and reservoir hosts. This study aimed to determine the association between temperature, air humidity, and weather conditions with the incidence of leishmaniasis in Montenegro during a seven-decade period (1945-2014) and to statistically compare and correlate the obtained data. In the studied period, there were 165 registered cases of leishmaniosis, 96.4%, in the coastal and central region of Montenegro, with an average incidence rate of 0.45/100.000. The visceral form of leishmaniosis predominated (99% of the cases), with only one case of cutaneous disease. Climate factors (average temperature, air humidity, and precipitation) had an impact on the occurrence of leishmaniosis in Montenegro. Air temperature elevated by 1 °C in all regions of Montenegro was significantly correlated with an increased incidence of leishmaniosis, by 0.150 (0.013 to 0.287; p < 0.05). In order to improve prevention and control of this disease, it is also necessary to investigate other factors with a possible impact on the number of cases of this neglected parasitosis.

Etiological and epidemiological characteristics of surgically treated radial nerve lesions: A 20-year single-center experience

Introduction

Radial nerve lesions present a clinical entity that may lead to disability, psychological distress, and job loss, and thus requires great attention. Knowledge of the etiology and exact mechanism of the nerve impairment is of great importance for appropriate management of these patients, and there are only a few papers that focused on these features in patients with surgically treated radial nerve lesions. The lack of studies presenting the etiology and injury mechanisms of surgically treated radial nerve lesions may be due to a relatively small number of specialized referral centers, dispersion to low-flow centers, and a greater focus on the surgical treatment outcomes.

Aim

The aim of this study was to describe the etiological and epidemiological characteristics of patients with surgically treated radial nerve lesions of various origins.

Methods

This retrospective study evaluated 147 consecutive patients with radial nerve lesion, treated in the department during the last 20 years, from January 1, 2001, until December 31, 2020.

Results

The majority of patients belonged to the working population, and 70.1% of them were male. Most commonly, the etiology of nerve lesion was trauma (63.3%) or iatrogenic injury (28.6%), while the less common origin was idiopathic (4.1%) or neoplastic (4.1%). The most frequent location of the lesion was in the upper arm, followed by the elbow and forearm. Fracture-related contusion was the most common mechanism (29.9%), followed by postoperative fibrosis (17.7%), lacerations (17.7%), and compression (15.6%).

Conclusion

Based on the fact that traumatic or iatrogenic injuries constitute the majority of cases, with their relevant mechanisms and upper arm predomination, it is crucial to raise awareness and understanding of the radial nerve injuries among orthopedic surgeons to decrease the numbers of these patients and properly preserve or treat them within the initial surgery.

Surgical Treatment of Radial Nerve Injuries Associated With Humeral Shaft Fracture-A Single Center Experience

Radial nerve injuries are often associated with humeral shaft fractures. The results of treatment of these injuries, by contemporary surgical approaches, remain diverse. In this paper we presented the outcomes and analyzed the patient, clinical, and surgical procedure related characteristics and factors that may influence the outcome overall, in 77 patients treated at Clinic for Neurosurgery, Clinical Center of Serbia during a 20 years period. The nerve injuries were verified by US and EMNG. The majority of patients were treated by neurolysis or sural nerve grafting, while only few were treated by direct suture. The final recovery was evaluated by muscle strength assessment and classified using MRC. We analyzed extension of the wrist, extension of the fingers including the thumb, and abduction of the thumb. There was a significant statistical difference in MRC grade following the treatment. The total rate of useful functional recovery was achieved in 69 (89.61%) out of all studied patients, out of whom 20 (28.99%) achieved excellent recovery, 26 (37.68%) achieved good recovery and 23 (33.33%) achieved fair recovery. Only 8 (10.39%) out of all studied patients achieved poor recovery. The injured nerves, that were preserved in continuity, acquired by a low-energy trauma, and treated earlier than the 6 months were associated with better functional outcome following the surgery. In addition, there was a trend of better functional improvement with aging, keeping in mind that the old were subjected to lower energy trauma. The expectant management followed by surgery of radial nerve injury associated with humeral shaft fracture should be around 3 months, and the surgical nerve repair should not be performed later than the 6 months after injury. The energy of trauma may be a factor predicting patient's final recovery following the treatment.

Factors Influencing Intraoperative Rupture of Intracranial Aneurysms

AIM

The study deals with intraoperative rupture of intracranial aneurysms (IOR) during microsurgery, analyzing factors that may be connected with IOR.

MATERIAL AND METHODS

During the three-year period (2006-2008), 934 patients were operated for aneurysms at the Institute of Neurosurgery, CCS, Belgrade. In total, 536 patients were observed.

RESULTS

IOR occurred in 14.7%. Male gender, seizures and timing of surgery proved to be risk factors for IOR. All other tested features had no significance. Localization {IOR rate 11.93% in ACM, 17.06% in ACA and 17.26% in ACI) and size (small: IOR in 68/439 (15.49%), large: 8/74 (10.8%), and very large: 3/23 (13.04%)} of aneurysm seemed to have an influence, but this could not be proved. The majority of IORs (58.23%) occurred in early surgery. Early operated patients: IOR occurred in 46/167 (27.54%), intermediary: 25/103 (24.27%), and delayed: 8/266 (3%) - with highly significant differences.

CONCLUSION

Age, hypertension, diabetes mellitus, cardiomyopathy, pregnancy, higher Fisher score, previous IOR, or the presence of vomiting and headache did not affect the occurrence of IOR, whereas the timing of surgery, male gender and epileptic seizures increased the risk. Localization and size of aneurysm tend to have an influence but statistical significance was not proved in this study.

INTRAOPERATIVE ANEURYSMAL RUPTURE: CLINICAL OUTCOME FOLLOWING OPEN SURGERY OR ENDOVASCULAR TREATMENT

The aim of this study was to evaluate and compare the outcomes of intraoperative aneurysmal rupture in patients with subarachnoid hemorrhage undergoing open surgical or endovascular treatment. This retrospective study included 742 patients with aneurysmal subarachnoid hemorrhage treated at the Clinical Department of Neurosurgery, Clinical Center of Serbia, during a three-year period. Among them, 167 (31.15%) were treated by clipping and 33 (16.01%) by coiling in the early phase (≤72 hours). The overall outcome and pretreatment variables were analyzed for each group, including between-group difference according to the occurrence of intraoperative aneurysmal rupture. Intraoperative aneurysmal rupture occurred in 14.7% of microsurgical and 2.4% of endovascular procedures. It was more frequent in early procedures as compared with delayed procedures (27.5% and 9.7% vs. 2.2% and 1.1%, respectively). On the contrary, mortality rates were lower in the surgical group (11.4%) than in the endovascular one (60.0%). On the basis of the results obtained, it is concluded that intraoperative aneurysmal rupture is more frequent after open than after endovascular treatment, but clinical outcome is more favorable in the former group.

Collateral branches of the brachial plexus as donors in nerve transfers

BACKGROUND/AIM

Nerve transfers in cases of directly irreparable, or high level extensive brachial plexus traction injuries are performed using a variety of donor nerves with various success but an ideal method has not been established. The purpose of this study was to analyze the results of nerve transfers in patients with traction injuries to the brachial plexus using the thoracodorsal and medial pectoral nerves as donors.

METHODS

This study included 40 patients with 25 procedures using the thoracodorsal nerve and 33 procedures using the medial pectoral nerve as donors for reinnervation of the musculocutaneous or axillary nerve. The results were analyzed according to the donor nerve, the age of the patient and the timing of surgery.

RESULTS

The total rate of recovery for elbow flexion was 94.1%, for shoulder abduction 89.3%, and for shoulder external rotation 64.3%. The corresponding rates of recovery using the thoracodorsal nerve were 100%, 93.7% and 68.7%, respectively. The rates of recovery with medial pectoral nerve transfers were 90.5%, 83.3% and 58.3%, respectively. Despite the obvious differences in the rates of recovery, statistical significance was found only between the rates and quality of recovery for the musculocutaneous and axillary nerve using the thoracodorsal nerve as donor.

CONCLUSION

According to our findings, nerve transfers using collateral branches of the brachial plexus in cases with upper palsy offer several advantages and yield high rate and good quality of recovery.

[Delayed epidural hematoma after mild head injury]

BACKGROUND

Traumatic delayed epidural hematoma (DEH) can be defined as insignificant or not seen on the initial CT scan performed after a trauma but seen on the subsequent CT scan as a "massive" epidural bleeding.

CASE REPORT

We presented two cases of traumatic DEH after mild head injury. Both patients were conscious and without neurological deficit on the admission. Initial CT scan did not reveal intracranial hematoma. Repeated CT scan, that was performed after neurological deterioration, revealed epidural hematoma in both cases. The patients were operated with a favorable surgical outcome.

CONCLUSION

Traumatic DEH could occur in the patients with head injuries who were conscious on the admission with a normal initial CT scan finding. Early detection of DEH and an urgent surgical evacuation were essential for a good outcome.