Fahr syndrome and neurological manifestations in hypoparathyroidism patients

Fahr syndrome is an uncommon (prevalence < 1/1.000.000) neurological disorder characterized by abnormal calcified deposits in the basal ganglia, nucleus dentatus, and cerebral cortex. These calcification can lead to various neurological manifestations. Distinguishing Fahr syndrome from Fahr disease is crucial due to differences in their etiology, location of lesions, prognosis, and therapy. Currently, Fahr disease lacks a specific treatment, while Fahr syndrome requires target intervention based on the underlying cause. A 35 years old female patient was presented to the emergency department with recurrent tonic-clonic seizures followed by the decreased consciousness. The patient had history of thyroidectomy surgery 7 years before, behavioral disturbances, hallucinations for past 1 week, and cataracts in both eyes. Laboratory examination showed low calcium levels (4 mg/dL), which can trigger seizures, and low PTH levels, indicating hypoparathyroid. A head CT scan without contrast displayed extensive bilateral calcification, particularly in the basal ganglia. Following stabilization, an EEG recording discovered diffuse encephalopathy. The patient received seizure management and maintenance medication of calcium with vitamin D. During the 3 months follow up, no sign of relapses were observed. Intracranial calcifications are often physiological but should be suspected as pathology in certain symptoms and calcification patterns. The presence of multiple intracranial calcifications, specifically in the basal ganglia, indicates Fahr disease or Fahr syndrome, which can cause various neurological manifestations. One of the etiologies of Fahr syndrome to consider is hypoparathyroid. Therefore, identifyisng and managing this etiology is crucial for preventing the progression of Fahr syndrome.

Spontaneous thrombosis of deep brain arteriovenous malformation in a patient with intraventricular and subarachnoid hemorrhage

The most common manifestation of brain arteriovenous malformations (BAVM) is intracranial hemorrhage. The incidence of ruptured BAVM is 3.5 per 100,000 people per year. The mortality rate of ruptured BAVM within 1 month after diagnosis was 12.7%. Spontaneous thrombosis occurs in less than 1.5% of ruptured BAVMs. This phenomenon was still elusive. Up until now, the gold standard of imaging examination has been cerebral digital subtraction angiography (DSA), whose sensitivity and specificity reach 100%. We reported the spontaneous thrombosis of a ruptured deep BAVM. An 18-year-old woman presented with severe headache and vomiting. The patient also complained of seizures. There was no body weakness, skewed face, or slurred speech. Cerebral computed tomography (CT) showed extensive hemorrhage in the ventricular system and subarachnoid space. Cerebral DSA showed a left subcortical BAVM and was found to have spontaneous thrombosis 3 weeks later when the patient was about to be embolized. Spontaneous thrombosis of ruptured BAVM may occur after intracranial hemorrhage. In this patient, spontaneous thrombosis occurred within 3 weeks.

Locked-in syndrome caused by extracranial and intracranial takayasu arteritis: A rare case report and radiological findings

Locked-in syndrome (LiS) is a condition of motor paralysis involving all the voluntary muscles of 4 extremities with retained consciousness and alertness. Meanwhile, Takayasu arteritis (TA) is a systemic inflammatory disease affecting large arteries, including the aorta and the branches. This disease often affects the extracranial arteries but rarely occurs in the intracranial arteries. An 18-year-old male presented with a sudden onset of decreased consciousness and bilateral weakness. The patient exhibited normal horizontal and vertical eye movements but presented with impairment of the trigeminal nerve, peripheral-type facial palsy, absence of gag reflex and tongue movement, and neck weakness. Physiological reflexes were increased bilaterally, while pathological reflexes were present on both sides. Autonomic function was impaired, and communication was impossible due to paralysis. Additionally, the patient displayed varying blood pressure readings between the right and left arms. The antinuclear antibody (ANA) and antismooth muscle (ASMA) antibody tests yielded negative results, while the electroencephalogram (EEG) showed normal readings. The cerebral angiogram indicated multiple internal and external stenoses, with total stenosis evident in the basilar artery. The patient was diagnosed with multiple extracranial and intracranial stenoses due to TA. Total stenosis of the basilar artery resulted in brainstem infarction, which led to the development of LiS. Meanwhile, the disturbance of the motor tracts in the ventral brainstem was the underlying cause of the LiS. This case report demonstrated a variety of atypical presentations of TA. The involvement of multiple extracranial and intracranial arterial was attributed to LiS.

A rare case report of spontaneous thrombosis in unruptured giant intracranial aneurysm

Unruptured giant intracranial aneurysms (GIAs) are characterized by their size, which exceeds 25 mm, and these conditions account for approximately 5% of all aneurysm cases. Furthermore, it typically develops in women during the fifth to seventh decade of life. Compared to small aneurysms, which cause subarachnoid hemorrhage, GIAs can manifest as masses or ischemic effects caused by thromboembolism. An elderly female patient, aged 67, was admitted to the hospital with a primary complaint of sudden facial sensory loss on the left side and vomiting. There was also a history of double vision accompanied by left ocular movement disturbance and gradually developed localized headache on the left side. Furthermore, a contrast head magnetic resonance angiography (MRA) revealed the presence of a high-flow giant aneurysm, measuring 30.7 × 31.8 × 27.2 mm in the cavernous segment of the left internal carotid artery (ICA). Cerebral angiography showed the absence of flow on the left ICA due to total occlusion. After cerebral angiography, the patient remained conscious but exhibited some neurological deficits, which were identical to the initial symptoms observed during hospitalization. Cases of spontaneous thrombosis in GIA are extremely rare. However, radiological examination, particularly angiography, can be used to diagnose spontaneous thrombosis in unruptured GIAs to ensure that the patient receives the right treatment.

Limb shaking movement as a rare manifestation of transient ischemic attacks caused by carotid stenosis disease: A case report

A limb shaking TIA is a less common form of TIA that manifests as involuntary movement and is frequently confused with focal motor epilepsy. A 64-year-old female presented with a 7-month history of episodic involuntary shaking movements affecting her left arm and leg before admission. These attacks primarily occurred after she rose from a sitting or lying down position to a standing position, and were relieved by simply returning to a sitting or lying position. A neurological examination revealed no motor or sensory deficits in either extremity. Her magnetic resonance angiogram (MRA) and carotid Doppler revealed right ICA stenosis in her brain. It is important to distinguish this limb shaking TIA from other conditions such as focal motor seizures. Importantly, early detection and treatment of the associated carotid artery occlusion can not only prevent the patient's TIA episode, but also lower the risk of future stroke.

A rare case of spontaneous thrombosis in saccular cerebral aneurysm in a patient with subarachnoid hemorrhage

Cerebral aneurysm is a known cause of spontaneous subarachnoid hemorrhage (SAH). Furthermore, this condition is often asymptomatic, but the occurrence of a rupture can lead to fatal complications. The incidence of spontaneous thrombosis in saccular aneurysm is rare, with an incidence rate of 1%-2%. The most common sites include the middle cerebral artery (MCA) (41%), posterior communicating artery (PCOMM) (15%), and posterior inferior cerebellar artery (PICA) (11%). A head computed tomography angiography (CTA) with contrast is a common diagnostic tool for detecting SAH in the temporoparietal area, hippocampal gyrus, and right fissure of Sylvie. In some cases, saccular aneurysm can be found in the segment bifurcation of the right middle cerebral artery. A cerebral angiography was carried out, specifically digital subtraction angiography, which revealed the presence of visible blister remnants of aneurysm in the form of spontaneous thrombosis. After 1 year, another angiography evaluation was performed to assess the condition of the patient. Furthermore, the results showed no evidence of recanalization and there were no new neurologic deficits. Although spontaneous thrombosis led to the healing of aneurysm in some cases, secondary recanalization remained a possibility. Therefore, it was essential to monitor any incidence of this complication. Precise knowledge of the mechanism of spontaneous thrombosis could lead to the development of new therapeutic approaches. Spontaneous thrombosis in cases of saccular aneurysm is a rare occurrence, which can provide temporary or permanent benefits to the patient. Therefore, periodic evaluation is required to assess the condition of the patient.

Bilateral gradual cortical blindness due to hemodynamic stroke: A case report

Cortical blindness refers to the loss of vision caused by a lesion affecting the geniculate calcarine visual pathway. Bilateral occipital lobe infarctions in the vascular territory of the posterior cerebral arteries are the most common cause of cortical blindness. However, bilateral cortical blindness gradual is rarely reported. Gradual bilateral blindness usually occurs in lesions other than stroke, such as tumors. We report a case of a patient with gradual cortical blindness caused by a nonocclusive stroke caused by hemodynamic compromise. A 54-year-old man diagnosed with bilateral cerebral ischemia after complaining of bilateral gradual vision loss and headache for 1 month. Initially, he only complained of blurred vision with >2/60 vision. However, his visual acuity worsened until he could only see hand movements and only light perception later on (with visual acuity of 1/∼). A computed tomography scan of the head revealed a bilateral occipital infarction, and cerebral angiography revealed multiple stenoses and near-total occlusion of the left vertebral artery ostium, underwent angioplasty and stenting. He has received dual antiplatelet and antihypertensive treatment. He got visual improvement with visual acuity 2/300 after 3 months of the treatment and procedure. Gradual cortical blindness caused by hemodynamic stroke is rare. The most common cause of posterior cerebral arteries infarction is embolism from the heart or vertebrobasilar circulation. With proper management and focusing on treating the etiology of these patients, vision improvements can be obtained in these patients.

Spontaneous subdural hematoma concomitant with subarachnoid hemorrhage and intracerebral hemorrhage due to ruptured brain arteriovenous malformation treated with curative embolization

Introduction

An arteriovenous malformation (AVM) consists of a tangled cluster of dilated blood vessels forming anomalous communication between arterial and venous systems without capillary bridging. The most likely manifestations of a ruptured AVM are intracerebral hemorrhage (ICH), subarachnoid hemorrhage (SAH), or intraventricular hemorrhage (IVH). Subdural hematoma (SDH) is exceptional in cases of ruptured brain arteriovenous malformation (BAVM).

Case Report

A 30-year-old female was referred to the Emergency Room with a major complaint of sudden thunderclap headache 1 day before admission. The patient also complained of double vision and left ptosis that lasted for 1 day. There was no other complaint or history of hypertension, diabetes, or trauma. Non-contrast head computed tomography (CT) showed ICH-SAH-SDH on the left side of the brain which was not typical of a hypertensive pattern. The secondary ICH has a score of 6, indicating that 100% of the bleeding might be caused by underlying vascular malformation. Furthermore, cerebral angiography showed cortical plexiform BAVM on the left occipital lobe, and the patient underwent curative embolization.

Discussion

Spontaneous SDH is very rare, and there are some hypotheses about the reasons for its occurrence. First, brain movement stretches the arachnoid layer that adheres to the AVM, resulting in direct bleeding into subdural space. Second, high-flow pia-arachnoid ruptured blood might extravasate into subdural space. Finally, the ruptured cortical artery that connects the cortex and dura layer (bridging artery) might also cause SDH. Some scoring systems are useful in BAVM, and this study selected endovascular embolization for the patient.

Conclusion

Brain AVM rupture usually causes ICH, SAH, or IVH. Clinicians must be more aware of spontaneous SDH because it might be caused by a vascular malformation, although it is rare.

Delayed Cerebral Ischemia after Embolization in Ruptured Spinal Arteriovenous Fistula with Subarachnoid Hemorrhage : A Case Report

Delayed cerebral ischemia (DCI) remains a devastating complication in subarachnoid hemorrhage (SAH), however, there were no present reports that is associated with a ruptured spinal arteriovenous fistula (sAVF). We would like to present a rare case of DCI following embolization of a ruptured perimedullary sAVF. Initially, the patient clinical symptoms mimic a SAH caused by a ruptured intracranial aneurysm. Further evaluation revealed that the SAH was caused by a ruptured perimedullary sAVF and the patient's condition improved following the embolization procedure. Three days later, the patient developed an acute left-sided facial and motor weakness, which persisted until the patient was discharged on the day-15 onset. A magnetic resonance imaging and angiography is performed 1.5 years after discharge and revealed no signs of cerebral infarction and hemorrhage. In this paper, we reported DCI after embolization in a ruptured sAVF with SAH, supported by evidence from the current literature. We would like to also stress the importance of complete spinal and cerebral vessel imaging to reveal the underlying abnormalities and determine the most appropriate intervention.

Acute subdural hematoma during sexual intercourse due to an aneurysm rupture on posterior communicating artery: a case report

Patients with an acute subdural hematoma (aSDH) usually have a history of head trauma, but some patients may present with spontaneous aSDH due to a ruptured aneurysm. Spontaneous aSDH is a rare manifestation of aneurysmal rupture. However, aneurysmal rupture remains a major cause of spontaneous aSDH. A 42-year-old man was brought to the emergency room because of a sudden loss of consciousness during sexual intercourse. The patient has seizures and weakness on the right side of his body. The patient has no history of trauma and has never taken anticoagulant or antiplatelet drugs, sexual aphrodisiacs, or other drugs. Physical examination revealed the Glasgow Coma Scale of E2V1M3, ptosis on the left eye, left pupil mydriasis, right central facial palsy, and right hemiparesis. Laboratory results showed hypercoagulopathy. Noncontrast head computed tomography scan revealed subdural hematoma with no subarachnoid or intraparenchymal hemorrhage. The patient underwent an emergency craniotomy, and the hematoma was evacuated. Cerebral angiography was performed 1 week later, revealing a saccular aneurysm in the left posterior communicating artery. The patient has successfully undergone endovascular coiling and was discharged from the hospital in good condition, fully conscious, with no weakness in half side of the body, but there is still third nerve palsy. Patients with pure aSDH without a history of trauma should consider the possibility of aneurysm rupture and perform an angiographic examination to rule out vascular malformations so that the patient can receive appropriate treatment.

Chronic pulsatile tinnitus and continuous vertigo due to very delayed diagnosis of single slow-flow dural arteriovenous

Tinnitus and vertigo are classic symptoms of inner ear disease. Dural arteriovenous fistulas (DAVF) are a rare type of acquired intracranial vascular malformation whose symptoms mimic inner ear disease, but what distinguishes it from other tinnitus is the characteristic of DAVF is pulsatile and heartbeat-synchronous. We present a 58-year-old male with chronic left-sided pulsatile tinnitus (PT) for 30 years and continuous vertigo for 3 years that took numerous consultations to establish a diagnosis after the onset of symptoms. Delay in diagnosis is caused by normal magnetic resonance imaging and an unrecognized subtle mass in the left temporal region by time-of-flight magnetic resonance angiography (TOF-MRA) at the screening test. As we know, TOF-MRA could not provide a clear picture to establish a slow-flow DAVF. Cerebral angiography, a gold standard diagnostic, revealed a Borden/ Cognard Type I single slow-flow DAVF in the left temporal region. The patient was treated with superselective transarterial embolization. After 1 week of follow-up, the symptoms of vertigo and PT were completely resolved.

Functional roles of lncRNA-TUG1 in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) or hepatoma is malignant cancer that starts from the main liver cells. Although various classical methods have been used for patients with HCC, various molecular mechanisms involved in HCC progression should be invested. Previous studies demonstrated that abnormal expression of long non-coding RNAs (lncRNAs) presented important roles in the pathogenesis of HCC cells. LncRNA TUG1 was found to mediate HCC cell growth, EMT, and metastasis. Therefore, targeting TUG1 and its downstream genes may be a suitable approach for patients with HCC. In this review, we summarized the potential roles of TUG1 in HCC.

Intravenous thrombolysis in patient with vertebrobasilar dolichoectasia and antiplatelet medication

Introduction: While the overall incidence of vertebrobasilar dolichoectasia (VBD) is less than 0.05%-0.06%, it is not uncommon in patients experiencing acute stroke. The influence of VBD on the outcome of intravenous (IV) thrombolysis therapy has not been widely studied. We present the following case of IV thrombolysis use in a patient experiencing acute stroke, who had an increased risk of bleeding due to prior antiplatelet use, and who had concomitant VBD. Case presentation: A 62-year-old man presented with weakness in the left extremities that had begun 1 hour prior to admission. The patient had a history of coronary artery disease and had been regularly taking antiplatelet medication. Upon arrival, the patient was in a decreased level of consciousness, with severe dysarthria, left central facial palsy, left lateralization, and a National Institute of Health Stroke Scale (NIHSS) score of 17. Computed tomography scan of the head showed no intracranial hemorrhage. The patient was administered IV thrombolysis at 2 hours and 45 minutes after symptom onset. Within the first 24 hours, the patient's NIHSS score decreased from 17 to 12, and the final NIHSS score prior to discharge was 7. The Head and neck angiography of this patient revealed VBD. Conclusion: This case demonstrated that IV thrombolysis is safe and effective for use in patients with acute ischemic stroke who have a history of antiplatelet usage and who experience concomitant VBD.

Recurrent stroke syndrome without abnormality on magnetic resonance imaging caused by stenosis of middle cerebral artery: A case report

Middle cerebral artery stenosis is the leading and the most frequent cause of stroke due to intracranial stenosis in Asia. Magnetic resonance imaging (MRI) is more sensitive than computed tomography of the head for detecting acute brain ischemia. We are reporting a case of a 28-year-old female with recurrent left hemiparesis. After the last attack, an improvement in motor function was seen in less than 24 hours. Though the restoration of motor functions is not complete yet, an MRI scan that was done two weeks later appeared normal. Ischemic stroke in middle cerebral artery stenosis is associated with hemodynamic stroke due to hypoperfusion or lack of blood flow to brain tissue. Recurrent strokes can be prevented by better medical management in patients through regulation and management of risk factors.

Hemifacial spasm caused by tortuous vertebrobasilar artery: a case report

Background

Hemifacial spasm is a rare movement disorder. Prevalence estimates worldwide was 14.5 per 100,000 women and 7.4 per 100,000 men. Hemifacial spasm generally caused by compression of blood vessels at the root entry zone of the facial nerve in the brainstem, tortuous anteroinferior cerebellar artery (AICA) and posteroinferior cerebellar artery (PICA). Direct compression by vertebrobasilar dolichoectasia (VBD) with coincidence cavernoma is extremely rare.

Case report

A 50-year-old woman with right hemifacial spasm for 1 year, with a history of hypertension for 10 years, did not take medication regularly. MRI MRA was performed showing suspicious dolichoectasia in the vertebrobasilar artery and cavernoma in the left basal ganglia. Then digital subtraction angiography was performed, it was found that the tortuous vertebrobasilar junction artery with a curve to the right caused right hemifacial spasm.

Conclusion

Vascular imaging examination is important to do to find the cause of hemifacial spasm suspected to be due to vascular causes. The finding of two types of intracranial vascular malformations should be explored further. Therefore, the selection of therapy and management becomes more appropriate.

Molecular Docking and Interaction Analysis of Propolis Compounds Against SARS-CoV-2 Receptor

Background: For many people, especially in developing countries, herbal medicine is the most traditional drug choice to treat all diseases including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 infection). Propolis is one of the popular herbal medicine which has various health benefits, particularly antiviral activity. In this molecular docking study, this investigation examined twenty-five kinds of propolis to bind SARS-CoV-2 protein with the main targets of ACE-2 and M-Pro receptors. Method: Propolis ligands were downloaded from PubChem, meanwhile ACE-2 and M-Pro receptors were downloaded from Protein Data Bank. Both ligands and targets were optimized by Pymol. The pharmacokinetic analysis was conducted using SwissADME. Molecular docking was done using PyRx 0.9 and its binding interaction was visualized by Discovery Studio. To predict the potential inhibition, this study compared the ligand-protein complex of propolis to ligands from the previous study. Result: Through the Lipinski rule, only five of twenty-five types of propolis were not qualified for the criterion. The ability to bind protein targets were various between ligands, the highest affinity to ACE-2 receptors were abietic acid, galangin, chrysin, kaempferol and acacetin, respectively. The binding affinity between ligand and M-Pro were seen weaker than ACE-2 receptor, while the strongest were kaempferol, abietic acid, acacetin, galangin and chrysin, respectively. Conclusion: Â Kaempferol is the most potent form of propolis to bind to ACE-2 and M-Pro receptors by assessing the binding affinity and the amount of amino acid residue formation when compared to control ligands. Keywords: ACE-2 receptor, COVID-19, Main protease, Molecular docking, Propolis, SARS-CoV-2

Production of Inflammatory Mediators in Conditioned Medium of Adipose Tissue-Derived Mesenchymal Stem Cells (ATMSC)-Treated Fresh Frozen Plasma

Background

Inflammation is the body’s first response to an illness that causes irritation or infection. Inflammation is tightly correlated with aging, which is a progressive degenerative process. Conditioned medium (CM) from adipose tissue-derived mesenchymal stem cells (CM-ATMSCs) has been shown to stimulate collagen synthesis and dermal fibroblast migration, as well as reduce wrinkles and improve wound healing. This study aimed to observe the production of inflammatory modulators – interleukin (IL)-1α, IL-6, IL-10, and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) – in CM-ATMSCs treated with fresh frozen plasma (FFP) at passages 3 (P3), 7, 11, and 15.

Material/Methods

ATMSCs P3 were obtained from liposuction of female donors, and the CM from ATMSCs was collected. Measurement of these cytokines was performed with ELISA.

Results

At many passages, IL-6, a proinflammatory modulator, was discovered to be the most powerful modulator among FFP- and non-FFP-treated cells. However, CM-ATMSCs treated with FFP and in the late passage have significant differences (P<0.05) compared to non-FFP treatments and in other passages in their effects on secretion of inflammatory modulators.

Conclusions

In conclusion, CM-ATMSC has the potential to secrete proinflammatory modulators.

Potential of Conditioned Medium of hATMSCs in Aging Cells Model

Skin aging is caused by the exposure cumulative of ultraviolet radiation, it leads reactive oxygen species (ROS) production in the skin. The conditioned medium of human Adipose Tissue-derived Mesenchymal Stem Cells (hATMSCs) can scavenge free radicals and increase the survival rate of skin cells under oxidative stress. This study examined the protective effects of Conditioned Medium (CM) of hATMSCs in H2O2-induced human skin fibroblast cell line (BJ). The aging cells model using H2O2-induced BJ cells were added CM-hATMSCs in concentrations (0, 10, 30%) and incubated in various time, furthermore BJ cells induced by various H2O2 concentrations (0, 50, 100, 200 µM) incubated for 1 h. The anti-aging potential were measured including viability, ROS and collagen levels in BJ cells which treated CM-hATMSCs. The median inhibitory concentration (IC50) of H2O2 on BJ cells for 1 h incubation was 107.87 μM and 91.25 μM for 10 min incubation. CM-hATMSCs increased the viability on aging model cells. CM-hATMSCs concentration 30% increased the viability of H2O2 50, 100, 200 µM-induced BJ cells. CM-hATMSCs concentration 25% decreased ROS, increased collagen level in H2O2 50, 100, 200 µM-induced BJ cells. CM-hATMSCs increase the viability cells, collagen level and decrease ROS level in aging model cells.

Comparative Preliminary Analysis of Umbilical Cord Blood-, Healthy Adult Peripheral Blood- and Myocardial Infarct Peripheral Blood-Derived Endothelial Progenitor Cells

BACKGROUND: Cardiovascular disease is a leading cause of death globally with the 287,000 deaths per years, characterized by declining of heart function caused by the reduction of heart capacity and lead to heart failure. Cell therapy using endothelial progenitor cells (EPCs) has a big potential for cardiovascular regeneration. EPCs are cells that have ability to differentiate into endothelial cells that can be mobilized and integrated into the defected blood vessel by angiogenesis. AIM: We aimed to seek the superior EPCs derived from MNCs for functional improvement of advanced heart failure patient by cell therapy using EPCs. MATERIALS AND METHODS: We did preliminary analysis to compare umbilical cord blood (UCB), healthy adult peripheral blood (PB)-, and myocardial infarct PB-derived EPCs characteristic and surface phenotypes. Different sources of each EPCs mononuclear cells were characterized by the expression of endothelial (cluster of differentiation [CD] 31, acethylated low-density lipoprotein, and von Willebrand) and hematopoietic stem cell (CD45, CD34, and CD133) surface markers with flow cytometry. RESULTS: In this study, EPCs and the conditioned medium (CM) have been produced and characterized in laboratory scale by comparing several sources of EPCs for instance UCB, PB from healthy people, and patients with myocardial infarction. We have shown that EPC characterizations from each group were not significantly different, but vascular endothelial growth factor and hepatocyte growth factor in UBC-derived CM-EPCs were higher than in PB. CONCLUSION: In conclusion, the UBC-derived EPCs might have a better potential for cardiovascular regeneration.

Effects of Starter Defect on Energy Release Rate of Three-Point End-Notch Flexure Tested Unidirectional Carbon Fiber Reinforced Polymer Composite

The mechanics of damage and fracture process in unidirectional carbon fiber reinforced polymer (CFRP) composites subjected to shear loading (Mode II) were examined using the experimental method of the three-point end-notch flexure (3ENF) test. The CFRP composite consists of [0o]16 with an insert film in the middle plane for a starter defect. A 3ENF test sample with a span of 50 mm and interface delamination crack length of 12.5 mm was tested to yield the load vs. deformation response. A sudden load drop observed at maximum force value indicates the onset of delamination crack propagation. The results are used to extract the energy release rate, GIIC, of the laminates with an insert film starter defect. The effect of the starter defect on the magnitude of GIIC was examined using the CFRP composite sample with a Mode II delamination pre-crack. The higher magnitude of GIIC for the sample with insert film starter defect was attributed to the initial straight geometry of the notch/interface crack and the toughness of the resin at the notch front of the fabricated film insert. The fractured sample was examined using a micro-computerized tomography scanner to establish the shape of the internal delamination crack front. Results revealed that the interface delamination propagated in a non-uniform manner, leaving a curved-shaped crack profile.

Management of super refractory status epilepticus

Super refractory status epilepticus ( SRSE ) is the status epilepticus in which the seizures continue for 24 hour or more after anesthetic medications to control and reappear when the patient is weaned from the anesthetic agent. Characteristic seizures are distinguished, by the presence and/or absence of motor seizure, into convulsive and non-convulsive status epilepticus (NCSE). An aggressive therapy is often needed after diagnosis is confirmed. Continuous monitoring during therapy is very important. The management for SRSE includes pharmacological and non-pharmacological treatment. Clinical and electrographic seizure suppression is the treatment goal. After that we need to find and treat the cause of seizures. Clinical judgement by the clinician is needed to identify the risks of excessive suppression of the nervous system, so as the morbidity and mortality is reduced for those patients who can survive but often have difficult and prolonged recovery. Received: 24 Oct 2018Reviewed: 28 Oct 2018Accepted: 6 Nov 2018 Citation: Kurniawan D, Machin A, Hidayati HB, Islamiyah WR. Management of super refractory status epilepticus. Anaesth Pain & Intensiv Care 2018;22 Suppl 1:S67-S72

Identification Acroporidae and Favidae by a newly approach called Reef Identification Knowhow Application-Reconstructed by 3D Imagery (RIKA-R3DI) Method

With an increase on coral reefs vulnerability worldwide, an efficient and an integrated monitoring technique are required. Photographic and video methods are now becoming more attractive rather than conventional technique to optimize diver time. In this research, the level of effectiveness of RIKA-R3DI method was evaluated using Agisoft Photoscan. The method was based on the reconstructed images in three dimensional image assisted by a computer with Agisoft Photoscan to facilitate data processing. This research aims to identify Acroporidae and Favidae as the models of coral reef-building species. The samples were collected from the waters of Beralas Pasir Island, Bintan Regency. Visual engineering was conducted in the form of 3D viewing with attention to the corallite shape and size, as well as the color of the corals. The result was successful in identifying 4 species, i.e. Acropora microphthalma, A. sarmentosa, Favia maritima, F. vietnamensis. The keys benefit of this methodologies are: •The RIKA-R3DI method allows to reduce diving time during direct visual observation.•The method has high accuracy and is non-invasive, since it does not touch directly to the coral.•The application of RIKA-R3DI can be used to identified the coral species and evaluate the coral health status base on the percent coverage.

Machining of bone: Analysis of cutting force and surface roughness by turning process

There are millions of orthopedic surgeries and dental implantation procedures performed every year globally. Most of them involve machining of bones and cartilage. However, theoretical and analytical study on bone machining is lagging behind its practice and implementation. This study views bone machining as a machining process with bovine bone as the workpiece material. Turning process which makes the basis of the actually used drilling process was experimented. The focus is on evaluating the effects of three machining parameters, that is, cutting speed, feed, and depth of cut, to machining responses, that is, cutting forces and surface roughness resulted by the turning process. Response surface methodology was used to quantify the relation between the machining parameters and the machining responses. The turning process was done at various cutting speeds (29-156 m/min), depths of cut (0.03 -0.37 mm), and feeds (0.023-0.11 mm/rev). Empirical models of the resulted cutting force and surface roughness as the functions of cutting speed, depth of cut, and feed were developed. Observation using the developed empirical models found that within the range of machining parameters evaluated, the most influential machining parameter to the cutting force is depth of cut, followed by feed and cutting speed. The lowest cutting force was obtained at the lowest cutting speed, lowest depth of cut, and highest feed setting. For surface roughness, feed is the most significant machining condition, followed by cutting speed, and with depth of cut showed no effect. The finest surface finish was obtained at the lowest cutting speed and feed setting.

In vitro degradation and cell viability assessment of Zn–3Mg alloy for biodegradable bone implants

This article reports the in vitro degradation and cytotoxicity assessment of Zn–3Mg alloy developed for biodegradable bone implants. The alloy was prepared using casting, and its microstructure was composed of Mg2Zn11 intermetallic phase distributed within a Zn-rich matrix. The degradation assessment was done using potentiodynamic polarization and electrochemical impedance spectrometry. The cell viability and the function of normal human osteoblast cells were assessed using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium and alkaline phosphatase extracellular enzyme activity assays. The results showed that the degradation rate of the alloy was slower than those of pure Zn and pure Mg due to the formation of a high polarization resistance oxide film. The alloy was cytocompatible with the normal human osteoblast cells at low concentrations (<0.5 mg/mL), and its alkaline phosphatase activity was superior to pure Mg. This assessment suggests that Zn–3Mg alloy has the potential to be developed as a material for biodegradable bone implants, but the toxicity limit must be carefully observed.

Elastic properties of polycaprolactone at small strains are significantly affected by strain rate and temperature

Tensile tests were conducted on polycaprolactone at various strain rates and temperatures. Focusing on the mechanical properties within only the small-strain elastic region, i.e. up to the inflection point in the stress–strain diagram, it was found that strain rate and temperature had significant effects on the polymer. This finding implies that the effects of strain rate and temperature on the elastic properties of polycaprolactone should be considered in the design and manufacture of rigidity-sensitive, load-bearing applications, including use as biomaterial for scaffolds in tissue engineering applications.