Detection of episodic nocturnal hypercapnia in patients with neurodegenerative disorders.

PURPOSE: Episodic nocturnal hypercapnia (eNH) in transcutaneous carbon dioxide pressure (PtcCO2) corresponding to rapid eye movement sleep hypoventilation is a useful biomarker for detecting nocturnal hypoventilation. However, the relationship between eNH and neurodegenerative diseases with sleep-related breathing disorders (SRBDs) is unknown. The aim of this study was to evaluate the relationship between eNH and nocturnal hypoventilation in neurodegenerative diseases. METHODS: Patients with neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), multiple system atrophy (MSA), Parkinson's disease, progressive supranuclear palsy, corticobasal syndrome, and idiopathic normal pressure hydrocephalus, were enrolled and received overnight PtcCO2 monitoring. The patients were divided into groups for eNH and sleep-associated hypoventilation (SH) prevalence analysis: A (ALS), B (MSA), and C (others). RESULTS: Among 110 patients, twenty-three (21%) and 10 (9%) of the patients met eNH and SH criteria, respectively. eNH and SH were significantly more frequent in groups A and B than in C. The prevalence of SH in the patients with eNH was 39% whereas most of patients with SH (90%) presented with eNH. Among patients with daytime carbon dioxide pressure in arterial blood ≤ 45 mmHg, eNH frequency was 13%, whereas none of the patients met SH criteria. The frequency of noninvasive positive pressure ventilation after PtcCO2 monitoring was significantly higher in those with than without eNH. CONCLUSIONS: eNH is common in patients with MSA and ALS who present with SRBD. eNH with overnight PtcCO2 monitoring is a useful biomarker to detect hypoventilation among neurodegenerative diseases with different SRBD mechanisms.

[Recanalization of an occluded artery of Percheron causing acute bilateral thalamic infarction].

An 87-year-old woman was admitted with acute onset of disturbed consciousness. On neurological examination, both pupils were dilated and non-reactive to light. Decerebrate rigidity was present. Babinski testing was positive. CTA suggested an isolated left P1 segment occlusion. The P2 segment was supplied from the left internal carotid artery via the posterior communicating artery. MRI showed bilateral paramedian thalamic infarctions. Because occlusion of the artery of Percheron was suspected, intravenous thrombolysis was performed. Digital subtraction angiography (DSA) revealed occlusion of the left P1 segment and spontaneous recanalization before endovascular treatment. Her consciousness improved immediately. When acute bilateral thalamic infarction suggests top of the basilar artery syndrome but no basilar artery occlusion is found, occlusion of the artery of Percheron should be considered. Thrombectomy of the affected P1 segment may be needed.

A case of ischemic stroke associated with protein-losing gastroenteropathy and protein S deficiency.

Protein-losing gastroenteropathies are characterized by an excessive loss of serum proteins into the gastrointestinal tract, resulting in hypoalbuminemia. Some rare cases are complicated with ischemic stroke. We report a 24-year-old woman who developed acute dysarthria and right hemiplegia 4 months after delivering her first baby by cesarean section. Diffusion-weighted magnetic resonance imaging showed a high-intensity signal in the left anterior cerebral artery territory and middle cerebral artery territory. She had marked hypoalbuminemia and decreased protein S activity. We identified protein-losing gastroenteropathy as the cause of the hypoalbuminemia, and she had a missense mutation of the PROS 1 gene, which was associated with decreased protein S activity. We speculated that the development of protein-losing gastroenteropathy accelerated the decline in protein S activity and caused cerebral infarction.

Prognosis Prediction Using Magnetic Resonance Spectroscopy and Oligoclonal Bands in Central Nervous System Methotrexate-associated Lymphoproliferative Disorder.

Central nervous system methotrexate-associated lymphoproliferative disorder (CNS-MTX-LPD) is rare, but its spontaneous regression has been observed in some patients after withdrawal of agents. We herein report three cases of primary CNS-MTX-LPD that received oral MTX for rheumatoid arthritis. Epstein-Barr virus and oligoclonal bands (OCBs) were positive, while proton magnetic resonance spectroscopy (1H-MRS) showed an elevated lipid peak and slightly elevated choline/N-acetylaspartate ratio in common. After MTX withdrawal, brain lesions showed spontaneous regression in all cases. Our patient's 1H-MRS findings and OCBs may reflect a non-monoclonal lymphoproliferative histology as benign-type lesions in CNS-MTX-LPD.

Clinical comorbidities correlated with a response to the cerebrospinal fluid tap test in idiopathic normal-pressure hydrocephalus.

AIMS: The mainstay of treatment for idiopathic normal-pressure hydrocephalus (iNPH) is spinal fluid shunting. A tap test (TT) is recommended as an indication of shunting. Patients with iNPH are often elderly and have multiple comorbidities affecting the shunting outcome. We investigated the factors affecting TT in patients with iNPH. METHODS: Seventy-five patients with iNPH were admitted to our department for a TT from April 2010 to May 2021. The patients were divided into a responsive group and an unresponsive group according to the clinical outcomes after TT on the Timed Up and Go Test (TUG), Mini-Mental State Examination (MMSE), or iNPH grading scale. Factors affecting the TT were compared between the responders and nonresponders. RESULTS: There were 38 patients (50.7%) in the TT responder group, and the prevalence of improvement was 82.9% in the TUG, 27.6% in the MMSE, and 76.3% in the iNPH grading scale. There were no significant differences in the vascular risk factors between the two groups. The prevalence of lumbar spondylosis, compression fracture, severe periventricular hyperintensity, deep and subcortical white matter hyperintensity (DSWMH), and old cerebral infarcts was significantly higher among the TT nonresponders. The logistic regression analysis showed that severe DSWMH and lumbar spondylosis were associated with a TT nonresponse (p < 0.001 and p = 0.003, respectively). Shunting was performed in 22 patients, 19 of whom were TT responders. CONCLUSION: Severe DSWMH and lumbar spondylosis were associated with a poor response to the TT in iNPH patients. We should consider risk factors when selecting candidates for shunt surgery.

Development of Microalgae Biosensor Chip by Incorporating Microarray Oxygen Sensor for Pesticides Sensing.

A microalgae (Pseudokirchneriella subcapitata) biosensor chip for pesticide sensing has been developed by attaching the immobilized microalgae biofilm pon the microarray dye spots (size 100 µm and pitch 200 µm). The dye spots (ruthenium complex) were printed upon SO3-modified glass slides using a polydimethylsiloxane (PDMS) stamp and a microcontact printer (µCP). Emitted fluorescence intensity (FI) variance due to photosynthetic activity (O2 production) of microalgae was monitored by an inverted fluorescent microscope and inhibition of the oxygen generation rate was calculated based on the FI responses both before and after injection of pesticide sample. The calibration curves, as the inhibition of oxygen generation rate (%) due to photosynthetic activity inhibition by the pesticides, depicted that among the 6 tested pesticides, the biosensor showed good sensitivity for 4 pesticides (diuron, simetryn, simazine, and atrazine) but was insensitive for mefenacet and pendimethalin. The detection limits were 1 ppb for diuron and 10 ppb for simetryn, simazine, and atrazine. The simple and low-cost nature of sensing of the developed biosensor sensor chip has apparently created opportunities for regular water quality monitoring, where pesticides are an important concern.

Fusion of ancestrulae germinated from statoblasts in plumatellid freshwater bryozoans.

Upon germination of a statoblast, the shell is split into two valves; a mucous pad which represents the basal portion of the body wall of the incipient zooid or ancestrula then appears from between the valves; lastly, a tiny polypide evaginates at the opposite site. When two or more contiguously located statoblasts (floatoblasts or sessoblasts) of the same species germinate simultaneously, their mucous pads often come into contact with each other. The walls of the mucous pads then disappear in the contact areas, thus uniting the coeloms of the ancestrulae. This type of fusion between mucous pads of statoblast-derived ancestrulae was ascertained in Plumatella emarginata, P. repens, P. casmiana, and Hyalinella punctata. The fusion is clearly species specific, and shows no clone specificity or allogeneic recognition. The fusibility test reported here seems to be a useful method for the examination of conspecificity in plumatellid bryozoans.