Morphological and Chemical Diversity within Japanese Laurencia Complex (Rhodomelaceae, Ceramiales, Rhodophyta)

Seaweeds of the red algal genus Laurencia are widely distributed worldwide in tropical, subtropical to temperate zones, and grow in Japan from Hokkaido to Okinawa. Laurencia is one of the most studied seaweeds by organic chemists because it produces a variety of compounds with unique structures. In Japan, various halogenated compounds have been found in Laurencia, while some species do not produce any halogenated compounds. Laurencia is one of the most difficult seaweeds to classify morphologically; however, the major halogenated secondary metabolites produced tend to be species-specific, and these compounds can be used as chemical markers for chemical systematics (chemotaxonomy). Similarly, it has been confirmed that domestic Laurencia species produce species-specific halogenated compounds of certain types. Laurencia is one of the "weedy seaweeds" that have not been effectively utilized at present, but it produces a wide variety of metabolites, so there is a good possibility that compounds with specific activity may be found. Thus, it can be seen that the secondary metabolites in Laurencia have many interesting aspects. In this review, we reported significant morphological features to distinguish species in this genus, and the morphological features, habitat, distribution, and chemical composition that help discriminate Japanese Laurencia species.

Halogenated Cyclic Monoterpenoids with Anti-Biofouling Activity from the Okinawan Red Marine Algae Portieria Hornemannii

The red algal genus Portieria is a prolific producer of halogenated monoterpenoids. In this study, we isolated and characterised monoterpenoids from the Okinawan red algae Portieria hornemannii. A new polyhalogenated cyclic monoterpenoid, 2(R)-chloro-1,6(S)-dibromo-3(8)(Z)-ochtoden-4(R)-ol (1), along with three known monoterpenoids, (2R,3(8)E,4S,6R)-6-bromo-2-chloro-1,4-oxido-3(8)-ochtodene (2), 1-bromo-2-chloroochtoda-3(8),5-dien-4-one (3), and 2-chloro-1-hydroxyochtoda-3(8),5-dien-4-one (4) were isolated from the methanol extract of three populations of P. hornemannii. These compounds were characterised using a combination of spectroscopic methods and chemical synthesis, and the absolute stereochemistry of compounds 1 and 2 was determined. In addition, all isolated compounds were screened for their anti-biofouling activity against the mussel Mytilus galloprovincialis, and 1 exhibited strong activity. Therefore, halogenated monoterpenoids have the potential to be used as natural anti-biofouling drugs.

Diversity of Halogenated Secondary Metabolites in Okinawan Aplysia argus Including 12-Hydroxypinnaterpene C and Their Feeding Targets

A new irieane-type diterpene, 12-hydroxypinnaterpene C (1), and 21 known compounds, angasiol acetate (2), angasiol (3), 11-deacetylpinnaterpene C (4), palisadin A (5), 12-acetoxypalisadin B (6), 12-hydroxypalisadin B (7), aplysistatin (8), luzodiol (9), 5-acetoxy-2-bromo-3-chloro-chamigra-7(14),9-dien-8-one (10), neoirietriol (11), neoirietetraol (12), (3Z)-laurenyne (13), cupalaurenol (14), cupalaurenol acetate (15), (3Z)-venustinene (16), 10-hydroxykahukuene B (17), aplysiol B (18), (3Z)-13-epipinnatifidenyne (19), 3Z,6R,7R,12S,13S-obtusenyne (20), (3Z,9Z)-7-chloro-6-hydroxy-12-oxo-pentadeca-3,9-dien-1-yne (21), and cholest-7-en-3,5,7-triol (22) were isolated from the digestive diverticula of Aplysia argus from the Ikei Island in Okinawa, Japan. The structures of these compounds were determined using spectroscopic methods such as NMR and HR-ESI-MS. These compounds were tested for their antibacterial activity against the phytopathogen Ralstonia solanacearum. Compounds 11 and 21 exhibited antibacterial activity at 30 μg/disc. In this study, we also discuss the types of red algae that A. argus feeds on in the shallow waters of Okinawa Prefecture.

Antifouling Brominated Diterpenoids from Japanese Marine Red Alga Laurencia venusta Yamada

The marine red algal genus Laurencia has abundant halogenated secondary metabolites, which exhibit novel structural types and possess various unique biological potentials, including antifouling activity. In this study, we report the isolation, structure elucidation, and antifouling activities of two novel brominated diterpenoids, aplysin-20 aldehyde (1), 13-dehydroxyisoaplysin-20 (2), and its congeners. We screened marine red alga Laurencia venusta Yamada for their antifouling activity against the mussel Mytilus galloprovincialis. Ethyl acetate extracts of L. venusta from Hiroshima and Chiba, Japan, were isolated and purified, and the compound structures were identified using 1D and 2D NMR, HR-APCI-MS, IR, and chemical synthesis. Seven secondary metabolites were identified, and their antifouling activities were evaluated. Compounds 1, 2, and aplysin-20 (3) exhibited strong activities against M. galloprovincialis. Therefore, these compounds can be explored as natural antifouling drugs.

Two New Eremophilane-Type Sesquiterpenoids from Japanese Liverwort Bazzania japonica

Two new eremophilane-type sesquiterpenoids, fusumaols A (1) and B (2), were isolated from the stem-leafy liverwort, Bazzaniajaponica collected in Mori-Machi, Shizuoka, Japan. Their structures were established using extensive spectroscopic (IR, MS, and 2D NMR) data, and the absolute configuration of 1 was determined by the modified Mosher's method. This is the first time eremophilanes have been discovered in the liverwort genus Bazzania. Compounds 1 and 2 were evaluated for their repellent activity against the adult population of the rice weevil Sitophilus zeamais using the modified filter paper impregnation method. Both sesquiterpenoids showed moderate repellent activities.

A trial of topiramate for patients with hereditary spinocerebellar ataxia

In an open pilot trial, six patients with various hereditary forms of spinocerebellar ataxia (SCA) were assigned to topiramate (50 mg/day) for 24 weeks. Four patients completed the protocol without adverse events. Of these four patients, topiramate was effective for three patients. Some patients with SCA could respond to treatment with topiramate.

New Marine Diterpenoid from the Okinawan Soft Coral, Lobophytum sp

A new lobane-type diterpenoid, loba-8,10,13(15)-triene-14,17,18-triol 17-acetate (1), and 5 known compounds, lobatriene (2), (17 R)-loba-8,10,13(15)-triene-17,18-diol (3), loba-8,10,13(15)-triene-14,17,18-triol 14,17-diacetate (4), loba-8,10,13(15)-triene-14,17,18-triol 14-acetate (5), and lobatrienetriol (6), were isolated from a population of Okinawan soft coral Lobophytum sp. The structures of these compounds were elucidated by spectroscopy, including nuclear magnetic resonance and high-resolution mass spectrometry. The cytotoxicity and genotoxicity of these compounds were tested using human lymphoblastoid TK6 cells.

Stereo-electroencephalography evidence of an eccentrically located seizure-onset zone around a polymorphous low-grade neuroepithelial tumor of the young: illustrative case

BACKGROUND

Polymorphous low-grade neuroepithelial tumor of the young (PLNTY) is a newly identified low-grade brain tumor with frequent epileptic presentation. Despite the facilitated use of invasive electroencephalography owing to the growing availability of stereo-electroencephalography (SEEG), intracranial features of tumor-related seizures are still scarcely described. This report provides the first description of SEEG-recorded seizures in PLNTY to provide an insight into its surgical strategy.

OBSERVATIONS

Spontaneous clinical seizures were recorded with SEEG in a young adult patient with drug-resistant epilepsy associated with a PLNTY in the left lateral temporal cortex. The seizure onset was characterized by low-voltage fast activity (LVFA) and showed eccentric localization with respect to the tumor: LVFA was localized in the anterior portion of the tumor and spread toward the adjacent polar cortex. The language risks associated with the resection of the posterior temporal cortex could thus be minimized.

LESSONS

PLNTY can show a focal and eccentric seizure-onset zone around the tumor. The present findings serve to improve the functional and seizure outcomes using the staged invasive approach in PLNTY.

New acetogenin katsuurallene from Laurencia saitoi collected from Katsuura, Japan

We examined the chemical constitution of the red alga Laurencia saitoi Perestenko, collected from Katsuura, Boso Peninsula, Chiba Prefecture, Japan. This specimen produced a new polyhalogenated acetogenin, named katsuurallene (1), which structure was determined by the spectral methods, along with known diterpene, deoxyparguerol (2) and triterpene, thyrsiferol (3). In this paper we describe the structural elucidation of katsuurallene together with some biological activities.

Postoperative striatal degeneration: a hitherto unrecognized impact of frontal disconnection surgery for drug-resistant epilepsy. Illustrative cases

BACKGROUND

Frontal disconnection surgery is a useful surgical option for patients with frontal epilepsy whose seizure onset zones are exceedingly large and thus are not amenable to conventional resective surgery. While it has the advantage of avoiding sequelae stemming from a large resection cavity, the impact of radical anatomofunctional disconnection of such a vast frontal region is not fully understood.

OBSERVATIONS

The authors have identified secondary degeneration in the striatum ipsilateral to the frontal disconnection surgery in two adult patients who had otherwise favorable postoperative outcomes following the surgery. On serial postoperative magnetic resonance imaging, the striatum showed transient restricted diffusion in the caudate head and rostral putamen around several weeks postoperatively and subsequent atrophy in the caudate head. The affected striatal regions (i.e., the anterior portion of the striatum) were congruent with the known fronto-striatal connectivity corresponding to the disconnected frontal regions anterior to the primary and supplementary motor areas. Both patients achieved 1-year seizure freedom without apparent disability related to the surgery.

LESSONS

The benign postoperative course despite the marked degenerative changes in the ipsilateral striatum supports the feasibility of the frontal disconnection surgery in otherwise inoperable patients with broad frontal epileptogenicity.

Comparison of Acute Withdrawal and Slow Taper of Antiseizure Medications during Video Electroencephalographic Monitoring: Efficacy for Shortening of Hospital Stay

Antiepileptic medications (ASMs) are withdrawn at the epilepsy monitoring unit to facilitate seizure recordings. The effect of rapid tapering of ASMs on the length of hospital stay has not been well documented. We compared the mean length of hospital stay between patients who underwent acute ASM withdrawal and slow dose tapering during long-term video electroencephalography (EEG) monitoring. We retrospectively investigated 57 consecutive patients admitted to the epilepsy monitoring unit regarding the mean length of hospital stay in the acute ASM withdrawal group (n = 30) and slow-taper group (n = 27). In the acute-withdrawal group, all ASMs were discontinued once the patients were admitted. In the slow-taper group, the doses of ASMs were gradually reduced by 15–30% daily. We also evaluated the safety of the acute-withdrawal and slow-taper protocols. The mean lengths of hospital stay were 3.8 ± 1.92 and 5.2 ± 0.69 days in the acute-withdrawal and slow-taper groups, respectively (p < 0.005). No severe adverse events, including status epilepticus, were observed. Acute ASM withdrawal has the advantage of significantly reducing the length of hospital stay over slow tapering, without any severe adverse effects.

Characteristics of olfactory dysfunction in patients with temporal lobe epilepsy

OBJECTIVE

To determine the characteristics of olfactory dysfunction in patients with temporal lobe epilepsy (TLE).

METHODS

Odor identification was assessed using the odor stick identification test for Japanese (OSIT-J, full score 12 points) in 65 patients with TLE and in 74 controls.

RESULTS

The mean OSIT-J score was significantly lower in patients with TLE (mean ± SD = 8.1 ± 2.8; median = 9) than in the control subjects (mean ± SD = 10.6 ± 1.1; median = 11) (P < 0.005). Olfactory dysfunction (hyposmia/anosmia) was associated with bilateral seizure foci and older age of onset in TLE. Patients who underwent temporal lobectomy for hippocampal sclerosis did not show significant decline after long-term recovery. The Indian ink part of OSIT-J was useful for the detection of olfactory deficits in patients with TLE (sensitivity = 47%, specificity = 93%). Patients with TLE tended to have preserved olfactory ability for stimulating odors and for familiar odors of daily life.

SIGNIFICANCE

We observed characteristic odor identification deficits for individual odors used in OSIT-J. Our study findings provide deeper insight into the underlying mechanism of olfactory function in patients with TLE and may be beneficial in the clinical management of these patients.

Plasma amino acids in patients with essential tremor

Essential tremor (ET) is one of the most common movement disorders. However, there are currently no accepted biomarkers for ET. This report suggested that concentration of plasma glutamic acid, aspartic acid, and taurine could be biomarkers for ET.

Two New Halogenated Compounds from the Marine Red Alga Laurencia nipponica Yamada from the Kunashiri and Etorofu Islands

The red alga Laurencia nipponica comprises various chemical races distributed relative to the ocean current in Japanese coastal areas. We investigated the chemical compositions and chemical races of L. nipponica distributed from the Kunashiri and Etorofu Islands, the confluence of the Soya warm current and Oya-shio cold current. Two new halogenated secondary metabolites, deacetylneonipponallene (1) and neopacifenol (2), along with four known compounds, deoxyprepacifenol (3), pacifenol (4), halo-chamigrene diether (5), and isolaurallene (6) were isolated from L. nipponica collected at Chikappunai, Kunashiri Island, while Zaimokuiwa (Kunashiri Island) and Sana (Etorofu Island) populations contained 3, 7-hydroxylaurene (7), 2,10-dibromo-3-chloro-9-hydroxy-α-chamigrene (8), and (3Z)-laurefucin (9). The structures of 1 and 2 were established using spectroscopic methods. The chemical races of L. nipponica distributed in this area were divided into 6- and 9-producing races. Interestingly, both races contained 4 as an additional race-index, as well as its derivatives, 2 and 5. To the best of our knowledge, this is the first example of a race comprising a mixture of two race-index compounds, suggesting that the convergence of two currents causes the production of new and diverse chemical races in this species.

Familial paroxysmal kinesigenic dyskinesia with a novel missense variant (Arg2866Trp) in NBEA

Paroxysmal kinesigenic dyskinesia (PKD) is a movement disorder characterized by episodic involuntary movement attacks triggered by sudden movements, acceleration, or intention to move. We ascertained two Japanese familial cases with PKD. The proband is a 22-year-old woman who had noted sudden brief (<30 s) of involuntary movements provoked by kinesigenic trigger such as starting to run, getting on a train, picking up a telephone receiver and so on at the age of 14. Interictal brain single photon emission computed tomography (SPECT) showed hyperperfusion in the left thalamus. A 46-year-old woman, the mother of the proband was also suffering from brief attacks triggered by starting to run in her high school days. On neurological examination, both showed no abnormality. Whole exome sequencing combined with rigorous filtering revealed two heterozygous nonsynonymous variants (NM_001447: c.8976G > C [p.Gln2992His] in FAT2 and NM_015678: c.8596C > T [p.Arg2866Trp] in NBEA). Real time quantitative PCR analysis of Nbea mRNA levels in the developing rat brain revealed peak at postnatal day 28 and decline at postnatal day 56. This result might match the most common clinical course of PKD from the point of view of the most common age at remission. NBEA has been reported to be responsible for neurodevelopmental disease accompanied by epilepsy. We concluded the variant in NBEA most likely to be responsible for our familial cases of PKD.

Structural Diversity, Anti-Fungal Activity and Chemosystematics of Bornean Liverwort Bazzania harpago (De Not.) Schiffner

Two terpenes; cneorubin X (1), (-)-gymnomitr-3(15)-en-4β-ol (2) as well as one benzoic compound; caffeic acid (3) were isolated from Bazzania harpago collected from Mt. Trus Madi, Sabah, Malaysia. The structures of these secondary metabolites were elucidated based on spectroscopic data (Infra-Red (IR), 1D and 2D Nuclear Magnetic Resonance (NMR), and Mass Spectrum (MS)). This is the first record that cneorubin X (1) was isolated from non-vascular plants and it exhibited active anti-fungal activity against Haliphthoros sabahensis and Haliphthoros milfordensis. Chemosystematics finding suggests that the Marchantiophyta (liverworts) genus Bazzania might have a closer chemical relationship to its sister group Bryophyta (mosses) genus Brachythecium, Kindbergia and Mnium, as well as Anthocerophyta (hornworts) genus Anthocerosin their evolutionary history.

Terpenoids from Marine Soft Coral of the Genus Xenia in 1977 to 2019

Members of the marine soft coral genus Xenia are rich in a diversity of diterpenes. A total of 199 terpenes consisting of 14 sesquiterpenes, 180 diterpenes, and 5 steroids have been reported to date. Xenicane diterpenes were reported to be the most common chemical skeleton biosynthesized by members of this genus. Most of the literature reported the chemical diversity of Xenia collected from the coral reefs in the South China Sea and the coastal waters of Taiwan. Although there was a brief review on the terpenoids of Xenia in 2015, the present review is a comprehensive overview of the structural diversity of secondary metabolites isolated from soft coral genus Xenia and their potent biological activity as reported between 1977 to 2019.

Individual response of humans to ionising radiation: governing factors and importance for radiological protection

Tissue reactions and stochastic effects after exposure to ionising radiation are variable between individuals but the factors and mechanisms governing individual responses are not well understood. Individual responses can be measured at different levels of biological organization and using different endpoints following varying doses of radiation, including: cancers, non-cancer diseases and mortality in the whole organism; normal tissue reactions after exposures; and, cellular endpoints such as chromosomal damage and molecular alterations. There is no doubt that many factors influence the responses of people to radiation to different degrees. In addition to the obvious general factors of radiation quality, dose, dose rate and the tissue (sub)volume irradiated, recognized and potential determining factors include age, sex, life style (e.g., smoking, diet, possibly body mass index), environmental factors, genetics and epigenetics, stochastic distribution of cellular events, and systemic comorbidities such as diabetes or viral infections. Genetic factors are commonly thought to be a substantial contributor to individual response to radiation. Apart from a small number of rare monogenic diseases such as ataxia telangiectasia, the inheritance of an abnormally responsive phenotype among a population of healthy individuals does not follow a classical Mendelian inheritance pattern. Rather it is considered to be a multi-factorial, complex trait.