Negative Influence of the Hunger State on Rule-observance Behavior in Mice

Developing social strategies to share limited resources equally and maximize the long-term benefits of conflict resolution is critical for appropriate social interactions. During social interactions, social decision-making depends not only on the external environment, but also on internal factors, such as hunger, thirst, or fatigue. In particular, hunger, which is related to food as a physical need, plays a dominant role in social decision-making. However, the consequences of food deprivation on social decision-making are not well understood. We have previously shown that mice with rule-observance behavior are capable of resolving conflict during social decision-making by observing a well-established social strategy based on reward zone allocation. Here, we developed a rule-observance behavior paradigm wherein the hunger state is achieved by applying food restrictions on mice prior to social behavior experiments. We found that the hunger state in mice deteriorated the established social strategy by decreasing reaction time, implying an increase in impulsivity. In contrast, the hunger state did not affect reward zone allocation, indicating no effect on spatial memory. This decrease in reaction time led to a significant increase in the percentage of violations during rule observance and a significant decrease in the amount of reward (payoff equity). Our study proposes that the hunger state exerts a detrimental effect on appropriate social decisionmaking by decreasing reaction time, increasing violation, and decreasing payoff equity in rule-observance behavior.

Direct Cannulation of a Calvarial Diploic Vein for Embolization of a Symptomatic Intraosseous Arteriovenous Fistula: A Case Report

Diploic arteriovenous fistulas (AVFs) or intraosseous dural AVFs are rare arteriovenous shunts. A diploic AVF is formed between a meningeal artery and an intraosseous diploic vein or the transosseous emissary vein, and the nidus is located exclusively within the bone. Currently, endovascular embolization with a transvenous approach is considered the treatment of choice for most dural AVFs. However, in the absence of an accessible venous channel, an alternate treatment approach should be considered. Herein, we report a case of a diploic AVF that was treated using embolization with transosseous direct cannulation.

The Protective Effects of Statins Towards Vessel Wall Injury Caused by a Stent Retrieving Mechanical Thrombectomy Device : A Histological Analysis of the Rabbit Carotid Artery Model

Objective@#: Endovascular mechanical thrombectomy (MT) has been regarded as one of the standard treatments for acute ischemic stroke caused by large vessel occlusion. Despite the wide use of stent retrievers for MT, arterial intimal damage caused when deployed stent is pulled has been a certain disadvantage. We hypothesized that statin could protect and stabilize vessel damage after endovascular MT using a stent retriever. In this animal study, we observed the protective effects of the statins towards MT-induced vessel wall injury. @*Methods@#: Twenty-eight carotid arteries of fourteen rabbits were used in the experiments with MT using stent retriever. We divided the rabbits into four groups as follows : group 1, negative control; group 2, positive control; group 3, statin before MT; and group 4, statin after MT. After MT procedures, we harvested the carotid arteries and performed histomorphological and immunohistochemical analyses. @*Results@#: In histomorphological analysis with hematoxylin and eosin and Masson’s trichrome stain, significant intimal thickening (p<0.05) was observed in the positive control (group 2), compared to in the negative control (group 1). Intimal thickening was improved in the statin-administered groups (groups 3 and 4 vs. group 2, p<0.05). We also observed that statin administration after MT (group 4) resulted in a more effective decrease in intimal thickness than statin administration before MT (group 3) (p<0.05). We performed immunohistochemical analysis with the antibodies for tumor necrosis factor-alpha (TNF-α), cluster of differentiation (CD)11b, and CD163. In contrast to the negative control (group 1), the stained percentage areas of all immunological markers were markedly increased in the positive control (group 2) (p<0.05). Based on statin administration, the percentage area of TNF-α staining was significantly reduced (p<0.05) in group 3, compared to the positive control group (group 2). However, significant differences were not observed for CD11b and CD163 staining. In group 4, no significant differences were observed for TNF-α, CD11b, and CD163 staining (p≥0.05). The differences in the percentage areas of the different markers between the statin-administered groups (groups 3 and 4) were also not revealed. @*Conclusion@#: We presented that statin administration before and after MT exerted protective effects towards vessel wall injury. The efficacy of statins was greater post-administration than pre-administration. Thus, statin administration in routine prescriptions in the peri-procedural period is strongly advised.

The Protective Effects of Statins Towards Vessel Wall Injury Caused by a Stent Retrieving Mechanical Thrombectomy Device : A Histological Analysis of the Rabbit Carotid Artery Model

Objective@#: Endovascular mechanical thrombectomy (MT) has been regarded as one of the standard treatments for acute ischemic stroke caused by large vessel occlusion. Despite the wide use of stent retrievers for MT, arterial intimal damage caused when deployed stent is pulled has been a certain disadvantage. We hypothesized that statin could protect and stabilize vessel damage after endovascular MT using a stent retriever. In this animal study, we observed the protective effects of the statins towards MT-induced vessel wall injury. @*Methods@#: Twenty-eight carotid arteries of fourteen rabbits were used in the experiments with MT using stent retriever. We divided the rabbits into four groups as follows : group 1, negative control; group 2, positive control; group 3, statin before MT; and group 4, statin after MT. After MT procedures, we harvested the carotid arteries and performed histomorphological and immunohistochemical analyses. @*Results@#: In histomorphological analysis with hematoxylin and eosin and Masson’s trichrome stain, significant intimal thickening (p<0.05) was observed in the positive control (group 2), compared to in the negative control (group 1). Intimal thickening was improved in the statin-administered groups (groups 3 and 4 vs. group 2, p<0.05). We also observed that statin administration after MT (group 4) resulted in a more effective decrease in intimal thickness than statin administration before MT (group 3) (p<0.05). We performed immunohistochemical analysis with the antibodies for tumor necrosis factor-alpha (TNF-α), cluster of differentiation (CD)11b, and CD163. In contrast to the negative control (group 1), the stained percentage areas of all immunological markers were markedly increased in the positive control (group 2) (p<0.05). Based on statin administration, the percentage area of TNF-α staining was significantly reduced (p<0.05) in group 3, compared to the positive control group (group 2). However, significant differences were not observed for CD11b and CD163 staining. In group 4, no significant differences were observed for TNF-α, CD11b, and CD163 staining (p≥0.05). The differences in the percentage areas of the different markers between the statin-administered groups (groups 3 and 4) were also not revealed. @*Conclusion@#: We presented that statin administration before and after MT exerted protective effects towards vessel wall injury. The efficacy of statins was greater post-administration than pre-administration. Thus, statin administration in routine prescriptions in the peri-procedural period is strongly advised.

Predicting Arachnoid Membrane Descent in the Chiasmatic Cistern in the Treatment of Pituitary Macroadenoma

Objective@#: Preoperative prediction of the arachnoid membrane descent in pituitary surgery is useful for achieving gross total removal and avoiding cerebrospinal fluid leakage resulting from tearing of the arachnoid membrane in the chiasmatic cistern. In this study, we analyzed the patterns of arachnoid membrane descent during or after pituitary tumor surgery and identified the factors related to this descent. @*Methods@#: Analysis was restricted to pituitary macroadenomas not extending into the third ventricle or over the internal carotid artery. To minimize confounding factors, patients who underwent revision surgery, those who had a torn arachnoid during operation or small medial diaphragma sellae (DS) opening, and subtotal resections were excluded. We enrolled 41 consecutive patients in this retrospective analysis. The degree of arachnoid descent was categorized using intraoperative videos. Preoperative magnetic resonance findings, including tumor height, suprasellar extension, and variables including DS area and medial opening size, tumor composition, and displacement of the pituitary stalk and gland were evaluated to determine their correlations with arachnoid membrane descent. @*Results@#: Arachnoid membrane descent was significantly correlated with DS area and medial opening size. Based on T2-weighted images (T2WI) magnetic resonance (MR) images, tumor composition was significantly associated with arachnoid membrane descent. Other factors were not significantly correlated with arachnoid membrane descent. @*Conclusion@#: T2WI of tumor composition and preoperative MR imaging of DS area and medial opening provided valuable information regarding arachnoid membrane descent. These parameters may serve as fundamental measures to facilitate complete resection of pituitary macroadenomas.

The Improving Effect of HL271, a Chemical Derivative of Metformin, a Popular Drug for Type II Diabetes Mellitus, on Aging-induced Cognitive Decline

In recent years, as the aging population grows, aging-induced cognitive impairments including dementia and Alzheimer's disease (AD) have become the biggest challenges for global public health and social care. Therefore, the development of potential therapeutic drugs for aging-associated cognitive impairment is essential. Metabolic dysregulation has been considered to be a key factor that affects aging and dementia. Adenosine monophosphate (AMP)-activated protein kinase (AMPK) is a primary sensor of cellular energy states and regulates cellular energy metabolism. Metformin (1,1-dimethylbiguanide hydrochloride) is a well-known AMPK activator and has been widely prescribed for type 2 diabetes mellitus (T2DM). Since the incidence of T2DM and dementia increases with aging, metformin has been considered to be one of the most promising drugs to target dementia and its related disorders. To that end, here, we tested the efficacy of metformin and HL271, a novel metformin derivative, in aging-induced cognitive decline. Water (control), metformin (100 mg/kg) or HL271 (50 mg/kg) were orally administered to aged mice for two months; then, the mice were subjected to behavioral tests to measure their cognitive function, particularly their contextual, spatial and working memory. AMPK phosphorylation was also measured in the drug-treated mouse brains. Our results show that oral treatment with HL271 (50 mg/kg) but not metformin (100 mg/kg) improved cognitive decline in aged mice. AMPK activation was correlated with behavior recovery after aging-induced cognitive decline. Taken together, these results suggest that the newly synthesized AMPK activator, HL271, could be a potential therapeutic agent to treat age-related cognitive decline.

Characteristic Signs on T2*-Based Imaging and Their Relationship with Results of Reperfusion Therapy for Acute Ischemic Stroke: A Systematic Review and Evidence to Date / 신경중재치료의학

PURPOSE: Characteristic signs – the susceptibility vessel sign (SVS) and the prominent hypointense vessel sign (PHVS) – on T2*-based magnetic resonance imaging (T2*MRI) can be seen for acute ischemic stroke with large artery occlusion. In this study, we investigated the evidence to support our hypothesis that these findings may help to predict outcomes after reperfusion therapy. MATERIALS AND METHODS: We searched for papers describing SVS and PHVS in patients treated with reperfusion therapy for acute ischemic stroke, and their functional/radiologic outcomes were systematically reviewed. RESULTS: Nine studies on the SVS and six studies on the PHVS were included. The pooled odds ratio (OR) of recanalization after intravenous thrombolysis or mechanical thrombectomy was not significantly different with the presence of SVS (OR, 0.615; 95% confidence interval [CI], 0.335–1.131 and OR, 0.993; 95% CI, 0.629–1.567). The OR of favorable functional outcome after reperfusion therapy in terms of the presence of PHVS varied (0.083 to 1.831) by study. CONCLUSION: Our meta-analysis of the published data showed that a SVS was not a predictive factor for recanalization after reperfusion therapy for acute ischemic stroke. Currently, the data available on T2*MRI are too limited to warrant reperfusion therapy in routine practice. More data are needed from studies with randomized treatment allocation to determine the role of T2*MRI.

Extended Pneumocephalus after Drainage of Chronic Subdural Hematoma Associated with Intracranial Hypotension : Case Report with Pathophysiologic Consideration

Chronic subdural hematoma (SDH) is a well-known disease entity and is traditionally managed with surgery. However, when associated with spontaneous intracranial hypotension (SIH), the treatment strategy ought to be modified, as classical treatment could lead to unwanted consequences. A 59-year-old man presented with a case of SIH that manifested as a bilateral chronic SDH. He developed fatal extensive pneumocephalus and SDH re-accumulation as a complication of burr-hole drainage. Despite application of an epidural blood patch, the spinal cerebrospinal fluid leak continued, which required open spinal surgery. Chronic SDH management should not be overlooked, especially if the exact cause has not been determined. When chronic SDH assumed to be associated with SIH, the neurosurgeon should determine the exact cause of SIH in order to effectively correct the cause.

Incomplete Clipping Resulting from Scissoring of the Clip Blades during Treatment of a Large Atheromatous Aneurysm

The cerebral aneurysm 'clip scissoring' phenomenon resulting from clip blade twisting is an unpredictable surgical complication. Additionally, incomplete clipping resulting from the presence of an atherosclerotic wall in the neck of the aneurysm can also cause unforeseen problems. Here, the authors present an unusual case of incomplete clipping of a large, atheromatous aneurysm resulting from clip scissoring, which was treated with additional endovascular coiling.

Analyses Using Micro-CT Scans and Tissue Staining on New Bone Formation and Bone Fusion According to the Timing of Cranioplasty via Frozen Autologous Bone Flaps in Rabbits : A Preliminary Report

OBJECTIVE: The timing of cranioplasty and method of bone flap storage are known risk factors of non-union and resorption of bone flaps. In this animal experimental study, we evaluated the efficacy of cranioplasty using frozen autologous bone flap, and examined whether the timing of cranioplasty after craniectomy affects bone fusion and new bone formation. METHODS: Total 8 rabbits (male, older than 16 weeks) were divided into two groups of early cranioplasty group (EG, 4 rabbits) and delayed cranioplasty group (DG, 4 rabbits). The rabbits of each group were performed cranioplasty via frozen autologous bone flaps 4 weeks (EG) and 8 weeks (DG) after craniectomy. In order to obtain control data, the cranioplasty immediate after craniectomy were made on the contralateral cranial bone of the rabbits (control group, CG).The bone fusion and new bone formation were evaluated by micro-CT scan and histological examination 8 weeks after cranioplasty on both groups. RESULTS: In the micro-CT scans, the mean values of the volume and the surface of new bone were 50.13+/-7.18 mm3 and 706.23+/-77.26 mm2 in EG, 53.78+/-10.86 mm3 and 726.60+/-170.99 mm2 in DG, and 31.51+/-12.84 mm3 and 436.65+/-132.24 mm2 in CG. In the statistical results, significant differences were shown between EG and CG and between DG and CG (volume : p=0.028 and surface : p=0.008). The histological results confirmed new bone formation in all rabbits. CONCLUSION: We observed new bone formation on all the frozen autologous bone flaps that was stored within 8 weeks. The timing of cranioplasty may showed no difference of degree of new bone formation. Not only the healing period after cranioplasty but the time interval from craniectomy to cranioplasty could affect the new bone formation.

Rebleeding of Ruptured Intracranial Aneurysms in the Immediate Postoperative Period after Coil Embolization

OBJECTIVE: Early rebleeding after coil embolization of ruptured intracranial aneurysms is rare, however serious and fatal results of rebleeding have been reported. We studied the incidence and angiographic and clinical characteristics of rebleeding of ruptured aneurysms occurring in the immediate postoperative period after coil embolization. MATERIALS AND METHODS: We analyzed patients who had aneurysmal subarachnoid hemorrhage and underwent coil embolization. Patients with dissecting aneurysms, blood blister-like aneurysms, fusiform aneurysms, and pseudoaneurysms were excluded. This study included 330 consecutive patients. The clinical and radiological data of 7 of these patients with acute rebleeding after coil embolization were reviewed. RESULTS: The incidence of rebleeding of ruptured aneurysms after coil embolization was 2.1% (7/330), and all cases of rebleeding occurred in the immediate postoperative period within 3 days after coiling. The radiological characteristics were as follows: anterior communicating artery (ACoA) aneurysm (71.4%, 5/7); presence of intracerebral hemorrhage (ICH, 71.4%, 5/7); dome-to-neck ratio < 2 (42.9%, 3/7); presence of bleb (42.9%, 3/7); and subtotal occlusion of aneurysm after coiling (14.3%, 1/7). A thrombolytic agent was administered in 1 patient and continued anticoagulation was performed in 2 patients. Rebleeding patients showed a very poor outcome (Glasgow Outcome Scale 1, 85.7%, 6/7). CONCLUSION: The prognosis of early rebleeding was very poor. Location of aneurysms on ACoA, the unilateral hypoplasia of A1 segment, presence of ICH and bleb, and adverse events during the procedure were probably associated with early rebleeding of ruptured intracranial aneurysms in the immediate postoperative period after coil embolization.

Spontaneous Occluded Anterior Communicating Artery Aneurysm during Coil Embolization Treated with One Coil Insertion into Remaining Stump

Spontaneous thrombosis of a ruptured aneurysm during coil embolization is a rare event, and some reports on recanalization of a spontaneous occluded ruptured aneurysm have been published. We report on a case of a 54-year-old male who presented with a subarachnoid hemorrhage due to rupture of a small aneurysm of the anterior communicating artery (ACoA). Cerebral angiography confirmed the presence of the ACoA aneurysm, but, during coil embolization, the aneurysm was near completely occluded with a remaining small neck. A small coil was inserted into the remaining stump of the neck to prevent recanalization, and the angiographic result at 1 year after coil embolization showed complete obliteration of the aneurysm.

Endovascular Treatment of Vertebral Artery Dissecting Aneurysms That Cause Subarachnoid Hemorrhage : Consideration of Therapeutic Approaches Relevant to the Angioarchitecture

OBJECTIVE: Intracranial ruptured vertebral artery dissecting aneurysms (VADAns) are associated with high morbidity and mortality when left untreated due to the high likelihood of rebleeding. The present study aimed to establish an endovascular therapeutic strategy that focuses specifically on the angioarchitecture of ruptured VADAns. METHODS: Twenty-three patients with ruptured VADAn received endovascular treatment (EVT) over 7 years. The patient group included 14 women (60.9%) and 9 men (39.1%) between the ages of 39 and 72 years (mean age 54.2 years). Clinical data and radiologic findings were retrospectively analyzed. RESULTS: Four patients had aneurysms on the dominant vertebral artery. Fourteen (61%) aneurysms were located distal to the posterior inferior cerebellar artery (PICA). Six (26%) patients had an extracranial origin of the PICA on the ruptured VA, and 2 patients (9%) had bilateral VADAns. Eighteen patients (78%) were treated with internal coil trapping. Two patients (9%) required an adjunctive bypass procedure. Seven patients (30%) required stent-supported endovascular procedures. Two patients experienced intra-procedural rupture during EVT, one of which was associated with a focal medullary infarction. Two patients (9%) exhibited recanalization of the VADAn during follow-up, which required additional coiling. No recurrent hemorrhage was observed during the follow-up period. CONCLUSION: EVT of ruptured VADAns based on angioarchitecture is a feasible and effective armamentarium to prevent fatal hemorrhage recurrence with an acceptable low risk of procedural complications. Clinical outcomes depend mainly on the pre-procedural clinical state of the patient. Radiologic follow-up is necessary to prevent hemorrhage recurrence after EVT.

Clinical Analysis and Surgical Considerations of Atherosclerotic Cerebral Aneurysms: Experience of a Single Center

OBJECTIVE: Atherosclerotic cerebral aneurysms are known to increase occurrence of thromboembolic events and occlusion of perforator vessels intraoperatively due to pathological changes in the vessels themselves. In the current study, we analyzed the points to be considered during surgery for atherosclerotic cerebral aneurysms and the postoperative results. MATERIALS AND METHODS: We retrospectively reviewed the medical records, radiological results, and surgical records, including intraoperative video recordings and photographs, of 262 patients who underwent cerebral aneurysm surgery. We then performed a detailed analysis of aneurysm features, surgical methods, and clinical outcomes. RESULTS: Among 278 aneurysms in 262 patients, 73 aneurysms in 67 patients showed atherosclerotic features (atherosclerotic group, AG), and 205 aneurysms in 195 patients showed no evidence of atherosclerosis (non-atherosclerotic group, NAG). In the AG, clipping with multiple permanent clips was performed in 14 aneurysms, and clip slippage was found in four cases. Six AG cases had a remnant neck after clipping, which was significantly more frequent than in the NAG (p < 0.05). Clinical outcomes and surgery-related complications did not differ significantly between the two groups. CONCLUSION: In the surgical repair of aneurysms, the incidence of ischemia, which is irreversible or severe, might be greater in atherosclerotic than in non-atherosclerotic aneurysms. In addition, multiple clips might be applied to atherosclerotic aneurysms for effective obliteration and an aneurysm neck might be left to avoid a region of atheroma.

Decompressive Surgery in Patients with Poor-grade Aneurysmal Subarachnoid Hemorrhage: Clipping with Simultaneous Decompression Versus Coil Embolization Followed by Decompression

OBJECTIVE: In addition to obliterating the aneurysm using clipping or coiling, decompressive surgery for control of rising intracranial pressure (ICP) is thought to be crucial to prevention of adverse outcomes in patients with poor grade aneurysmal subarachnoid hemorrhage (aSAH). We evaluated the clinical characteristics of patients with poor-grade aSAH, and compared outcomes of aneurysmal clipping with simultaneous decompressive surgery to those of coil embolization followed by decompression. MATERIALS AND METHODS: In 591 patients with aSAH, 70 patients with H-H grade IV and V underwent decompressive surgery including craniectomy, lobectomy, and hematoma removal. We divided the patients into two groups according to clipping vs. coil embolization (clip group vs. coil group), and analyzed outcomes and mortality. RESULTS: Aneurysmal clipping was performed in 40 patients and coil embolization was performed in 30 patients. No significant differences in demographics were observed between the two groups. Middle cerebral artery and posterior circulation aneurysms were more frequent in the clip group. Among 70 patients, mortality occurred in 29 patients (41.4%) and 61 patients (87.1%) had a poor score on the Glasgow outcome scale (scores I-III). No significant difference in mortality was observed between the two groups, but a favorable outcome was more frequent in the coil group (p < 0.05). CONCLUSION: In this study, despite aggressive surgical and endovascular management for elevated ICP, there were high rates of adverse outcomes and mortality in poor-grade aSAH. Despite poor outcomes overall, early coil embolization followed by decompression surgery could lead to more favorable outcomes in patients with poor-grade aSAH.

Asymptomatic Penetration of the Oculomotor Nerve by a De Novo Aneurysm Associated with Severe Atherosclerotic Stenosis of the Supraclinoid Internal Carotid Artery

A 70-year-old woman presented with headaches and recurrent stroke symptoms. During five years, the patient has been treated for cerebral infarction associated with severe atherosclerotic stenosis of the internal carotid artery. Three-year follow-up magnetic resonance angiography showed a tiny de novo aneurysm arising from the distal part of atherosclerotic internal carotid artery. And 5-year follow-up three-dimensional CT angiogram demonstrated a definite aneurysm enlargement as large as requiring treatment. During dissection of aneurysm, the oculomotor nerve was found to be penetrated with the growing de novo aneurysm. The authors report a case of a de novo aneurysm, which resulted from atherosclerotic stenosis of the internal carotid artery at the supraclinoid portion, that was found to be penetrating the oculomotor nerve with no ocular palsy.

Coincidental Occurrence of Acute In-stent Thrombosis and Iatrogenic Vessel Perforation During a Wingspan Stent Placement: Management with a Stent In-stent Technique / 신경중재치료의학

We presented a case that an acute in-stent thrombosis after the deployment of a Wingspan stent was successfully managed with a stent in-stent technique. Because vessel perforation and subarachnoid hemorrhage were iatrogenically developed during the procedure, we were unable to use the thrombolytic agents to correct the in-stent thrombosis. When a thrombotic complication following an intracranial stent placement occurs with a coincidentally hemorrhagic complication, the stent in-stent technique should be considered as a treatment option.

Comprehensive analysis of microRNA-mRNA co-expression in circadian rhythm

To investigate the potential role of microRNA (miRNA) in the regulation of circadian rhythm, we performed microarray-based expression profiling study of both miRNA and mRNA in mouse liver for 48 h at 4-hour intervals. Circadian miRNA-mRNA target pair is defined as the pair both elements of which show circadian expression patterns and the sequence-based target relationship of which can be predicted. Circadian initiators, Clock and Bmal1, showed inversely correlated circadian expression patterns against their corresponding miRNAs, miR-181d and miR-191, targeting them. In contrast, circadian suppressors, Per, Cry, CKIe and Rev-erba, exhibited positively correlated circadian expression patterns to their corresponding miRNAs. Genomic location analysis revealed that intronic region showed higher abundance of cyclic than non-cyclic miRNAs targeting circadian genes while other (i.e., 3'-UTR, exon and intergenic) regions showed no difference. It is suggested that miRNAs are involved in the regulation of peripheral circadian rhythm in mouse liver by modulating Clock:Bmal1 complex. Identifying specific miRNAs and their targets that are critically involved in circadian rhythm will provide a better understanding of the regulation of circadian-clock system.

A Surgical Case of Lymphocytic Hypophysitis with Progressive Visual Worsening

Lymphocytic hypophysitis is a clinically rare disease, and it has been known to be an autoimmune disease which mainly affects pregnant women at the end of gestation or right after delivery. The authors experienced a case of lymphocytic hypophysitis in a 29-year-old pregnant woman with rapid progressing visual disturbance. Sella MRI showed a mass-like lesion of hypophysis and hypertrophy of pituitary stalk with evidences of hypopituitarism. Cesarean section was done and then TSA was performed. The pathologic diagnosis was lymphocytic hypophysitis. After TSA, visual acuity was improved and visual field defect was recovered. She was given thyroid hormone replacement therapy because of transient partial hypopituitarism for 6 months after surgery. One must consider the probability of lymphocytic hypophysitis, if there are alteration of visual acuity and visual field defect which aggravate rapidly during pregnancy due to mass effect, decreased serum hormonal levels shown in hypopituitarism and sella MRI findings of hypertrophy of pituitary stalk and enlargement of pituitary gland.

Partial rescue of the Na+-Ca2+ exchanger (NCX1) knock-out mouse by transgenic expression of NCX1

The null mutation of cardiac Na+-Ca2+ exchanger (NCX1) gene in mice caused death of embryo in utero at embryonic day (ED) 9.0-9.5 and this embryonic lethality appears resulted from abnormal heart development. In the present study, we investigated whether transgenic re-expression of NCX1 in mutant cardiac myocytes could rescue these lethal defects. Transgenic mice expressing the canine NCX1 in a cardiac specific manner were bred into the NCX1 knock-out background but did not prevent the fetal lethality associated with the NCX1 null allele. However, the NCX1 knock-out embryos with an NCX1 transgene survived with heart beatings until ED 10.5 which was one day longer than the survival of the NCX1 knock-out embryos (ED 9.5). At ED 10.5, however, the partially rescued NCX1 embryos might have succumbed to the lack of an organized vasculature in the yolk sacs. The placental labyrinth layer was reduced in size and largely avascular. The transgenic re-expression of NCX1 rescued heart beatings and survived longer, but was still insufficient for the mice to be completely rescued. Importantly, NCX1 was observed to express in the yolk sac and the placenta of wild type mice. The results suggest that defects in extra-embryonic compartments are causal to the lethality, and that NCX1 may play an important role in establishing vascularization in extra-embryonic tissues.