1.Neurological melioidosis in East Malaysia: Case series and review of the literature
Si Lei Fong ; Jin ShyanWong ; Ai Huey Tan ; Soon Chai Low ; Chong Tin Tan
Neurology Asia 2017;22(1):25-32
Melioidosis is an infectious disease caused by an aerobic, non-spore forming gram negative bacillus,
Burkholderia pseudomallei. It is known to be of high incidence in parts of rural South East Asia,
and in Northern Australia. Pneumonia is the commonest manifestation. We report here three cases of
neurological melioidosis from the registry of 169 cases of melioidosis in Bintulu Hospital, Sarawak,
East Malaysia, with a review of neurological melioidosis in the literature. The annual incidence of
melioidosis is estimated to be 8 per 100,000 populations in the Bintulu district. Neurological melioidosis
accounts for 1.8% of our melioidosis cases. A review of 76 cases of neurological melioidosis reported
in the literature inclusive of our 3 cases shows that localized brain or spinal inflammation or abscess
is the most common manifestation occurring in 80% of patients. Close to half (53%) have intra axial
abscess (brain or spinal cord), a quarter (27%) have extra axial lesions only (epidural or subdural
collection, osteomyelitis or scalp abscess), and another quarter (27%) have both intra and extra axial
lesions. Thus, B. pseudomallei appears to be unique among the bacterial central nervous system
infection to be able to affect the brain and its contiguous tissues, crossing the tissue plane particularly
resulting in osteomyelitis, scalp abscess and vice versa. Two thirds of the neurologicalmelioidosis
patients have only neurological disease with no evidence of disease elsewhere.
Key words: Burkholderia pseudomallei; neurological melioidosis; Bintulu; Sarawak; Malaysia
Melioidosis
2.Research Progress of the Effects of Monocular Visual Impairment on Binocular Vision
Si-Lei TAN ; Jie-Min CHEN ; Meng WANG ; Shu ZHOU ; Wen-Tao XIA
Journal of Forensic Medicine 2018;34(1):67-72
Binocular vision refers to a progress of analysing and integrating the binocular visual signals into a whole and three-dimensional sensory perception by higher nerve centre. In this process, the interac-tion between the two eyes results in the changes of output signal, which is called binocular interaction. Through a series of subjective and objective experiments, it can be concluded that binocular interaction can be divided into three types: facilitation, summation and suppression, and the forms of binocular in-teraction in different visual states are different. In general, the visual signal is processed by binocular in-teraction, so that there are some differences between binocular vision and monocular vision. The extent of the difference can be affected by the damage of monocular vision and then affects the binocular vision. Thus, it is necessary for forensic scientists to further study the effects of the monocular visual impairment on visual function. Based on relevant data, this paper reviews the mechanism of the monocular visual impairment in binocular vision, the research methods and the application prospect in forensic science.
3.Hyperglycemia-Associated Hemichorea-Hemiballismus with Predominant Ipsilateral Putaminal Abnormality on Neuroimaging
Si Lei FONG ; Ai Huey TAN ; Kar Foo LAU ; Norlisah RAMLI ; Shen Yang LIM
Journal of Movement Disorders 2019;12(3):187-189
No abstract available.
Neuroimaging
4.Comparison of Measurement Methods of Exophthalmos and Its Forensic Significance
lei Si TAN ; min Jie CHEN ; ying Xiao YU ; wen Mao WANG ; pei Pei ZHUO ; Shu ZHOU ; tao Wen XIA
Journal of Forensic Medicine 2017;33(4):353-356
Objective To compare the differences between Hertel exophthalmometry and CT on exophthalmos measurement,and explore its practical application value in forensic medicine.Methods Fifty-six normal individuals without eye injuries or diseases were selected as the control group.The absolute values of exophthalmos were measured in the standardized CT image workstation.The difference of binocular exophthalmos was compared in normal group.Forty-seven cases with unilateral orbital fracture were divided into injured eye group and normal eye group according to the presence of binocular orbital fractures.The differences of the absolute values of eophthalmos from the same eye and the relative values of eophthalmos between two eyes for same person measured by Hertel exophthalmometry and CT were analyzed.Results There was no statistical difference of exophthalmos between the normal eyes measured by CT method.In the normal eye group,the absolute value of exophthalmos measured by CT method was (16.66±5.41) rm,which was (16.16±4.45)mm when measured by the Hertel exophthalmometry method.There was no statistical difference between two groups (P>0.05).In the injured eye group,there was statistical difference between the absolute values of exophthalmos measured by two measurement methods (P<0.05).There was no statistical difference of the relative values of exophthalmos between the injured eyes and the normal eyes by two measurement methods (P>0.05).Conclusion CT method has a good consistency with Hertel exophthalmometry,which can be applied into the practice of medicolegal expertise.
5.Chorea in Sporadic Creutzfeldt-Jakob Disease
Ai Huey TAN ; Tsun Haw TOH ; Soon Chai LOW ; Si Lei FONG ; Kah Kian CHONG ; Kee Wei LEE ; Khean Jin GOH ; Shen Yang LIM
Journal of Movement Disorders 2018;11(3):149-151
No abstract available.
Chorea
;
Creutzfeldt-Jakob Syndrome
6.Progress on the Muscle Function Evaluation and Its Forensic Application
Pei-Pei ZHUO ; Dong GAO ; Dan RAN ; Qing XIA ; Si-Lei TAN ; Wen-Tao XIA
Journal of Forensic Medicine 2018;34(6):665-671
Accurate evaluation of muscle function helps to understand the recovery of muscle, bone, nervous system diseases or injuries, especially for muscle dysfunction caused by peripheral nerve injury.Therefore, the methods of muscle function evaluation have been the focus of researchers, with new methods having been constantly proposed.Muscle strength testing is an important part of muscle function evaluation.Besides hand muscle strength assessment, currently used muscle function assessments include simple instrumental test, isokinetic muscle test, electrophysiological test, etc.In addition, the application of needle electromyography, motor unit number estimation, motion unit index in muscle function evaluation has also been reported for several times.This paper reviews the research progress and practical application of these methods.
7.How many more seizure remission can we achieve with epilepsy surgeries in a general epilepsy population?
Si-Lei Fong ; Kheng-Seang Lim ; Khine Yee Mon ; Sherrini Ahmad Bazir ; ChongTin Tan
Neurology Asia 2020;25(4):467-472
Background & Objective: We knew that 63.6% of the epilepsy population can be seizure free with
the use of anti-epileptic drugs (AED), but are unsure how many more with epilepsy surgeries. We
aimed to determine the additional remission rate achieved with epilepsy surgeries in addition to AED.
Methods: We analysed the seizure outcome among epilepsy patients seen retrospectively over oneyear period in University Malaya Medical Centre, Malaysia, which provides all levels (level 1-4) of
epilepsy cares, in response to anti-epileptic drug (AED) and epilepsy surgeries. The seizure outcome
was categorised into remission and drug-resistant, according to ILAE definition of drug resistance.
Results: There were 909 patients seen during the study period, majority with focal epilepsy (63.3%),
and Chinese (37.4%). Of those, 409 (45.0%) were in seizure remission, 238 (26.2%) had drug-resistant epilepsy and 262 (28.8%) uncertain. Only the remission and drug-resistant groups (N=647) were included in subsequent analysis. The mean age of onset in drug-resistant group was 14.8±12.3 years old, which was significantly younger than the remission group (20.8±16.8, p<0.05). There were 40 (54.8%) patients who underwent resective epilepsy surgeries (10 were lesion-negative cases). The
seizure freedom rate with epilepsy surgery was 60.0% (n=24). Overall, a total of 59.5% of patients
were in seizure remission with AED, with an additional 3.7% with epilepsy surgery.
Conclusion: There were 3.7% of epilepsy patients achieved seizure remission with epilepsy surgeries
in a general epilepsy cohort in addition to AEDs.
8.Exercise-induced Modulation of Ferroptosis: Potential Mechanisms for Improvement in Parkinson’s Disease
Dong-Lei LU ; Wen-Yu ZHANG ; Si-Jie TAN ; Feng-Ying YANG
Progress in Biochemistry and Biophysics 2024;51(11):2880-2896
Parkinson’s disease (PD) is a neurodegenerative disorder characterized by muscle rigidity, resting tremor, and postural instability, which severely impair the quality of life in middle-aged and elderly individuals. PD’s pathogenesis is complex, involving oxidative stress, immune inflammation, and genetic factors. Despite extensive research, precise therapeutic targets for PD remain elusive, necessitating further investigation into its underlying mechanisms. Recent studies highlight the pivotal role of regional brain iron overload, oxidative stress, and lipid peroxidation in PD’s pathogenesis. Ferroptosis, a form of regulated cell death driven by iron dependency and lipid peroxidation, has emerged as a critical factor in PD pathology. This review examines the relationship between ferroptosis and PD and explores the potential of exercise as a therapeutic intervention to modulate ferroptosis and alleviate PD symptoms. Ferroptosis, distinct from other forms of cell death such as necrosis, autophagy, pyroptosis, and apoptosis, is characterized by mitochondrial shrinkage, reduced cristae, and membrane collapse, without nuclear fragmentation, DNA cleavage, or caspase activation. It is induced by the accumulation of intracellular Fe2+, which enhances lipid peroxidation and reactive oxygen species (ROS) generation, ultimately leading to cell death. Studies show disrupted iron metabolism in PD patients, with elevated iron levels in dopaminergic neurons of the substantia nigra correlating with disease severity. Iron chelation therapy has shown promise in alleviating PD symptoms by reducing brain iron levels, highlighting the significance of iron metabolism in PD pathogenesis. Lipid peroxidation, a hallmark of ferroptosis, involves the oxidation of polyunsaturated fatty acids (PUFAs) in cell membranes, compromising membrane integrity and increasing permeability. Elevated lipid peroxidation in the substantia nigra contributes to neuronal damage in PD. Enzymes such as ACSL4 and LPCAT3, crucial in PUFA metabolism, play significant roles in ferroptosis. Exercise has been shown to modulate these enzymes, potentially reducing lipid peroxidation and preventing ferroptosis in PD. Glutathione (GSH) metabolism is another crucial factor in ferroptosis regulation. GSH depletion impairs ROS detoxification, exacerbating oxidative stress and lipid peroxidation. PD patients exhibit reduced GSH levels in the substantia nigra, making dopaminergic neurons more vulnerable to oxidative damage. Exercise enhances GSH synthesis and activity, mitigating oxidative stress and ferroptosis in PD. α-Synuclein aggregation, a hallmark of PD, is closely linked to iron metabolism and oxidative stress. Excessive α‑synuclein binds to iron, promoting its aggregation and inducing ferroptosis. Exercise has been found to reduceα-synuclein accumulation and its pathological phosphorylation, potentially through the upregulation of neuroprotective proteins like DJ-1 and Irisin. These proteins enhance antioxidant defenses and facilitate α‑synuclein degradation, providing a protective effect against PD progression. Additionally, glutamate excitotoxicity, driven by dysregulated glutamate metabolism and receptor activity, contributes to ferroptosis in PD. Exercise modulates glutamate levels and receptor expression, reducing excitotoxicity and iron-induced neuronal damage. In conclusion, emerging research suggests that exercise may inhibit ferroptosis through multiple mechanisms, including regulation of iron metabolism, enhancement of antioxidant defenses, reduction of α-synuclein aggregation, and modulation of glutamate metabolism. These findings highlight the potential of exercise as a non-pharmacological intervention in the prevention and treatment of PD. Further research is needed to elucidate precise mechanisms and optimize exercise protocols for maximum therapeutic benefit.
9.Summary of experience in emergency operation of infective endocarditis
Lei CHEN ; Yunsheng YU ; Ke SI ; Tan LIU
Chinese Journal of Integrated Traditional and Western Medicine in Intensive and Critical Care 2024;31(3):346-349
Objective To summarize the experience of infectous endocarditis(IE)emergency surgery.Methods A total of 76 patients admitted to the department of cardiovascular surgery of the First Affiliated Hospital of Soochow University from January 2019 to August 2022 were retrospectively analyzed.Summarize and share treatment experience.Results Out of 76 IE patients,55 cases(72.4%)were male and 21 patients(27.6%)were female.The ratio of male to female was 2.6∶1.The age ranged from 17-76 years,with a mean of(52.1±15.6)years.The positive rate of blood culture was 25.0%(19 cases).A total of 57 cases(75.0%)were cured,8 cases(10.5%)were discharged automatically,9 cases(11.8%)were improved,and 2 patients(2.6%)died before operation.There were 30 patients(39.5%)who underwent mitral valve surgery,24 patients(31.6%)who underwent aortic valve surgery,12 patients(15.7%)who underwent mitral and aortic valve surgery;15 patients(19.7%)with congenital heart disease,69 patients(90.8%)with rheumatic heart disease;66 patients(93.0%)with left cardiac system vegetations,4 patients(5.6%)with right cardiac systems vegetations;13 patients(17.1%)who requied emergency surgery,and no death.Conclusions The mortality of IE is high,and the current effective treatment is still surgery,but the timing of surgery is still controversial.This study summarized the experience of several cases of emergency operation and concluded that as long as the patient's condition permits,early operation can improve the survival rate of patients and improve the prognosis.
10.Assessment of the Original Height of L1~2 after Vertebral Compression Fracture.
Pei Pei ZHUO ; Mao Wen WANG ; Xiao Ying YU ; Lei WAN ; Si Lei TAN ; Jie Min CHEN ; Wen Tao XIA
Journal of Forensic Medicine 2018;34(4):359-362
OBJECTIVES:
To explore the assessment method of original height of L1-2 after vertebral compression fracture and its application value in forensic clinical practice.
METHODS:
A total of 154 normal thoracic and lumbar X-ray films were collected, and 140 cases were used as experimental group while 14 cases as validation group. The heights of anterior (Ha) and posterior (Hp) vertebral body of T₁₂-L₃ vertebrae in each X-ray image were measured. In the experimental group, the correlation analysis between HaL₁ and HaT₁₂, HpT₁₂, HpL₁, HaL₂ and HpL₂ was carried out, and regression equation was established via fitting. The correlation analysis between HaL₂ and HaL₁, HpL₁, HpL₂, HaL₃, HpL₃ was performed, and the regression equation was also established via fitting. The difference between the predicted and measured values of HaL₁ and HaL₂ in validation group was compared.
RESULTS:
In the 140 normal subjects, HaL₁ (y₁) was well correlated with HaT₁₂ (x₁) and HaL₂(x₂), and the multiple linear regression equation was y₁=2.545+0.423 x₁+0.486 x₂ (determining coefficient R²=0.712, P<0.05; F=169.206, P<0.05). There was no significant difference between the predicted and actual measured values of HaL₁ in the validation group ( P>0.05). HaL₂ (y₂) was well correlated with HaL₁ (x₃) and HaL₃ (x₄), and the multiple linear regression equation was y₂=4.354+0.530 x₃+0.349 x₄ (determining coefficient R²=0.689, P<0.05; F=151.575, P<0.05). There was no significant difference between the predicted and actual measured values of HaL₂ in the validation group ( P>0.05).
CONCLUSIONS
It is more appropriate to evaluate the original height of L₁ or L₂ single vertebrae by comparing with the height of the anterior edge of the upper and lower adjacent vertebral bodies.
Aged
;
Fractures, Compression
;
Humans
;
Lumbar Vertebrae/diagnostic imaging*
;
Middle Aged
;
Spinal Fractures/surgery*
;
Thoracic Vertebrae/diagnostic imaging*