Photo-steered rapid and multimodal locomotion of 3D-printed tough hydrogel robots

Hydrogels are an ideal material to develop soft robots. However, it remains a grand challenge to develop miniaturized hydrogel robots with mechanical robustness, rapid actuation, and multi-gait motions. Reported here is a facile strategy to fabricate hydrogel-based soft robots by three-dimensional (3D) printing of responsive and nonresponsive tough gels for programmed morphing and locomotion upon stimulations. Highly viscoelastic poly(acrylic acid-co-acrylamide) and poly(acrylic acid-co-N-isopropyl acrylamide) aqueous solutions, as well as their mixtures, are printed with multiple nozzles into 3D constructs followed by incubation in a solution of zirconium ions to form robust carboxyl-Zr4+ coordination complexes, to produce tough metallo-supramolecular hydrogel fibers. Gold nanorods are incorporated into ink to afford printed gels with response to light. Owing to the mechanical excellence and small diameter of gel fibers, the printed hydrogel robots exhibit high robustness, fast response, and agile motions when remotely steered by dynamic light. The design of printed constructs and steering with spatiotemporal light allow for multimodal motions with programmable trajectories of the gel robots. The hydrogel robots can walk, turn, flip, and transport cargos upon light stimulations. Such printed hydrogels with good mechanical performances, fast response, and agile locomotion may open opportunities for soft robots in biomedical and engineering fields.

Reversible Snapping of Constrained Anisotropic Hydrogels Upon Light Stimulations

Creatures, such as Venus flytrap and hummingbirds, capable of rapid predation through snap-through transition, provide paradigms for the design of soft actuators and robots with fast actions. However, these artificial "snappers" usually need contact stimulations to trigger the flipping. Reported here is a constrained anisotropic poly(N-isopropylacrylamide) hydrogel showing fast snapping upon light stimulation. This hydrogel is prepared by flow-induced orientation of nanosheets (NSs) within a rectangular tube. The precursor containing gold nanoparticles is immediately exposed to UV light for photopolymerization to fix the ordered structure of NSs. Two ends of the slender gel are clamped to form a buckle with bistability nature, which snaps to the other side upon laser irradiation. Systematic experiments are conducted to investigate the influences of power intensity and irradiation angle of the laser, as well as thickness and buckle height of the gel, on the snapping behaviors. The fast snapping is further used to kick a plastic bead and control the switch state. Furthermore, synergetic or oscillated snapping of the gel with two buckles of opposite directions is realized by inclined irradiation of a laser or horizontal irradiation with two lasers, respectively. Such light-steered snapping of hydrogels should merit designing soft robots, energy harvests, etc.

Magneto-Orientation of Magnetic Double Stacks for Patterned Anisotropic Hydrogels with Multiple Responses and Modulable Motions

Reported here is a multi-response anisotropic poly(N-isopropylacrylamide) hydrogel developed by using a rotating magnetic field to align magnetic double stacks (MDSs) that are fixed by polymerization. The magneto-orientation of MDSs originates from the unique structure with γ-Fe₂ O₃ nanoparticles sandwiched by two silicate nanosheets. The resultant gels not only exhibit anisotropic optical and mechanical properties but also show anisotropic responses to temperature and light. Gels with complex ordered structures of MDSs are further devised by multi-step magnetic orientation and photolithographic polymerization. These gels show varied birefringence patterns with potentials as information materials, and can deform into specific configurations upon stimulations. Multi-gait motions are further realized in the patterned gel through dynamic deformation under spatiotemporal light and friction regulation by imposed magnetic force. The magneto-orientation assisted fabrication of hydrogels with anisotropic structures and additional functions should bring opportunities for gel materials in biomedical devices, soft actuators/robots, etc.

Patterned Electrode Assisted One-Step Fabrication of Biomimetic Morphing Hydrogels with Sophisticated Anisotropic Structures

Anisotropic structures are ubiquitous in nature, affording fascinating morphing behaviors. Biomimetic morphing materials can be developed by spatially controlling the orientations of molecules or nanofillers that produce anisotropic responses and internal stresses under external stimuli. However, it remains a serious challenge to fabricate materials with sophisticated anisotropic architectures. Here, a facile strategy to fabricate morphing hydrogels with elaborately ordered structures of nanosheets, which are oriented under distributed electric field and immobilized by polymerization to form a poly(N-isopropylacrylamide) matrix, is proposed. Diverse sophisticated anisotropic structures are obtained by engineering the electric field through the patterns and relative locations of the electrodes. Upon heating, the monolithic hydrogels with through-thickness and/or in-plane gradients in orientation of the nanosheets deform into various three-dimensional configurations. After incorporating gold nanoparticles, the hydrogels become photoresponsive and capable of programmable motions, for example, dynamic twisting and flipping under spatiotemporal stimuli. Such a strategy of using patterned electrodes to generate distributed electric field should be applicable to systems of liquid crystals or charged particles/molecules to direct orientation or electrophoresis and form functional structures. The biomimetically architectured hydrogels would be ideal materials to develop artificial muscles, soft actuators/robots, and biomedical devices with versatile applications.

Serum lactic acid level predicts poor myocardial perfusion and in-hospital outcomes in patients undergoing primary percutaneous coronary intervention

Background

Elevated serum lactic acid level is associated with poor outcomes in patients with critical diseases like shock. However, the clinical implication of this biomarker in patients with acute myocardial infarction remains unclear.

Purpose

We aimed to explore the predictive power of serum lactic acid level on admission for in-hospital outcomes in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention (pPCI).

Methods

Consecutive patients undergoing pPCI with available data on serum lactid acid level were evaluated for eligbility in this retrospective cohort study. The primary outcome was all-cause death during hospitalization. Enzymatic infarct size and major adverse cardiovascular events (MACE, defined as a combination of all-cause death, recurrent myocardial infarction, and unplanned repeated revascularization) were considered secondary outcomes. Independent preditors of in-hospital death were determined by multiple logisic regression analysis. Odds ratio (OR) with 95% confidence interval (CI) was used to demonstrate the association. The predictive power of serum latictic acid level for in-hospital death was evaluated through receiver operator characteristic curve, which generated C-statictic. A combination model was further constructed by adding serum latictic acid level to the Global Registry of Acute Coronary Events (GRACE) risk score (LA-GRACE risk score). The linear dependence between serum lactic acids level and othe clinical variables was analysed using Spearman rank correlation.

Results

Of the 302 patients enrolled in the current analysis, 15 (5.0%) died during hospitalization. Serum lactic acid level (OR=1.657, 95% CI: 1.115 to 2.463, p=0.012)and left ventricular ejection fraction (OR=0.858, 95% CI: 0.767 to 0.959, p=0.007) were the only two independent predictors of in-hospital death. The C-statistic of serum lactic acid level for predicting in-hospital death was 0.886 (95% CI: 0.793 to 0.979). The LA-GRACE risk score improved the C-statistic of the GRACE score from 0.898 to 0.911 (p=0.294), with continuous net reclassification improvement of 0.567 (p=0.023) and integrated discrimination improvement of 0.206 (p=0.003). High serum lactic acid level was also asscoiated with larger enzymatic infarct size (p=0.002) and MACE (p=0.004). Further, it significantly correlated with white blood cell counts (r=0.264, p<0.001), serum creatinine level (r=0.189, p=0.001), and systolic blood pressure (r=−0.122, p=0.034).

Conclusion

Serum lactic acid level on admission is asscoiated with poor myocardial perfusion and in-hospital outcomes in patients with acute myocardial infarction undergoing pPCI. It may contribute to better risk stratification in these populations.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This study was supported by the National Program on Key Basic Research Project of China (Grant No: 2019YFC0840601 and 2014CBA02003), National Natural Science Foundation of China (Grant No: 81870267, 81970295, 81521001, 81670318 and 81570314), Grant of Shanghai Shenkang on Key Clinical Research Project (Grant No: SHDC2020CR2015A and SHDC12019104), Grant of Shanghai Science and Technology Committee (Grant No: 19MC1910300, 18411950200 and 20JC1410800), Key Medical and Health Projects of Xiamen Province (No: 3502Z20204004), Grant of Shanghai Municipal Commission of Health and Family Planning (Grant No: 2017YQ057), Grant of Zhongshan Hospital Affiliated to Fudan University (Grant No: 2018ZSLC01), VG Funding of Clinical Trials (2017-CCA-VG-036) and Merck Funding (Xinxin-merck-fund-051). ROC of lactic acid and GRACE score

Photoregulated Gradient Structure and Programmable Mechanical Performances of Tough Hydrogels with a Hydrogen-Bond Network

Gradient materials exist widely in natural living organisms, affording fascinating biological and mechanical properties. However, the synthetic gradient hydrogels are usually mechanically weak or only have relatively simple gradient structures. Here, we report on tough nanocomposite hydrogels with designable gradient network structure and mechanical properties by a facile post-photoregulation strategy. Poly(1-vinylimidazole-co-methacrylic acid) hydrogels containing gold nanorods (AuNRs) are in a glassy state and show typical yielding and forced elastic deformation at room temperature. The gel slightly contracts its volume when the temperature is above the glass-transition temperature that results in a collapse of the chain segments and formation of denser intra- and interchain hydrogen bonds. Consequently, the mechanical properties of the gels are enhanced, when the temperature returns to room temperature. The mechanical performances of hydrogels can also be locally tuned by near-infrared light irradiation due to the photothermal effect of AuNRs. Hydrogels with arbitrary two-dimensional gradients can be facilely developed by site-specific photoirradiation. The treated and untreated regions with different stiffness and yielding stress possess construct behaviors in stretching or twisting deformations. A locally reinforced hydrogel with the kirigami structure becomes notch-insensitive and exhibits improved strength and stretchability because the treated regions ahead the cuts have better resistance to crack advancement. These tough hydrogels with programmable gradient structure and mechanics should find applications as structural elements, biological devices, etc.

Distributed Electric Field Induces Orientations of Nanosheets to Prepare Hydrogels with Elaborate Ordered Structures and Programmed Deformations

Living organisms use musculatures with spatially distributed anisotropic structures to actuate deformations and locomotion with fascinating functions. Replicating such structural features in artificial materials is of great significance yet remains a big challenge. Here, a facile strategy is reported to fabricate hydrogels with elaborate ordered structures of nanosheets (NSs) oriented under a distributed electric field. Multiple electrodes are distributed with various arrangements in the precursor solution containing NSs and gold nanoparticles. A complex electric field induces sophisticated orientations of the NSs that are permanently inscribed by subsequent photo-polymerization. The resultant anisotropic nanocomposite poly(N-isopropylacrylamide) hydrogels exhibit rapid deformation upon heating or photoirradiation, owing to the fast switching of permittivity of the media and electric repulsion between the NSs. The complex alignments of NSs and anisotropic shape change of discrete regions result in programmed deformation of the hydrogels into various configurations. Furthermore, locomotion is realized by a spatiotemporal light stimulation that locally triggers time-variant shape change of the composite hydrogel with complex anisotropic structures. Such a strategy on the basis of the distributed electric-field-generated ordered structures should be applicable to gels, elastomers, and thermosets loaded with other anisotropic particles or liquid crystals, for the design of biomimetic/bioinspired materials with specific functionalities.

Photodirected Morphing Structures of Nanocomposite Shape Memory Hydrogel with High Stiffness and Toughness

Shape memory hydrogels have drawn increasing attention in recent years. Practical applications require these hydrogels to have good mechanical properties as well as contactless stimulations to trigger the shape deformations. Here we report a stiff and tough shape memory hydrogel that can transform to various configurations sequentially by phototriggered site-specific deformations. Response of the shape memory hydrogel to near-infrared (NIR) light irradiation was achieved by incorporating gold nanorods (AuNRs) into the glassy gel matrix of poly(methacrylic acid-co-methacrylamide) without compromising the excellent mechanical properties. Owing to the photothermal effect of the AuNRs, the localized temperature rise led to a dramatic decrease in Young's modulus (from 200 to 2 MPa) of the prestretched hydrogel and bending deformation with a programmable direction and amplitude. More complex three-dimensional configurations can be obtained by multidirectional prestretching and shape memorizing the individual parts of the nanocomposite hydrogel. Furthermore, the AuNRs embedded in the gel were aligned along the prestretching direction, leading to anisotropic plasmon resonance. These photomediated programmable deformations of tough shape memory hydrogels should find applications in the biomedical and engineering fields.

[Clinical study of chondrosarcoma in the jugular foramen]

Objective:To explore the diagnosis and surgical treatment of chondrosarcoma in the jugular foramen (JF).Method:This study lies on the retrospective analysis about 72 patients with secondary hyperparathyroidism who had parathyroid gland resection in our hospital from 2010 to 2017. All of 72 cases are examined by color doppler ultrasound,99mTC-MIBI nuclide imaging and magnetic resonance imaging. According to the gold standard pathological diagnosis after surgery, we compute the sensitivity and the specificity of various imaging examination and analyse these statistics by rate card square test with SPSS 19.0 software.Result:The main complaints in the patients included hearing loss, facial palsy and tinnitus. All patients achieved total removal with IFTA-A as initial treatment. Three cases underwent facial nerve grafting and preoperative cranial nerve dysfunction didn't aggravate in our cases. No recurrence or major complication has been identified till the latest follow up.Conclusion:Chondrosarcoma in the JF is a rare entity. Misdiagnosis frequently occurs in clinical practice. Special attention should be paid to the clinical characteristics and radiological findings when encounters a lesion in the jugular foramen. It is believed that the complete resection of the tumor should be the initial choice for patients with chondrosarcoma in the JF.

[The study on the targets of the optical evoked auditory brainstem response on the cochlea of guinea pig stimulating by infrared laser]

Objective: To identify the targets of the infrared laser stimulating on the cochlea of guinea pig which evoked auditory brainstem response (oABR), and explore the mechanisms of the infrared neurostimulation. Methods: A polished optical fiber with 200 μm diameter (NA=0.22) was planted into the scala tympani of guinea pigs to stimulate the cochlea of both the normal hearing and acute deafened guinea pigs. The direction of the fiber distal was changed to radiate different regions of the scala tympani, recording the oABR respectively. Differences of energy thresholds and amplitudes of oABR between normal hearing and acute deafened animals was concerned, and different responses were recorded as the optical path of laser fiber being changed to investigate the targets of the infrared laser stimulation. Immunofluorescence was used to detect the changes of inner and outer hair cells, and spiral ganglion neurons 7 days post-deafening, to looking for the probable association with the oABR changes at the same stimulus. SPSS 18.0 software was used to analyze the data. Results: Inner and outer hair cells were damaged in basal and middle turn, butresidual hair cells were observed in apical turn.Only when the optical fiber pointed to Rosenthal's canal stimulated the spiral ganglion region directly could the oABR be evoked. No response was recorded while the fiber pointed to other directions. Conclusion: Infrared laser stimulates cochlea evoked oABR generats from the response of spiral ganglion directly, the spiral ganglion neurons are the target of infrared stimulation.

Association study of plasma NT-proBNP levels and severity of acute coronary syndrome

The aim of this study was to investigate the N-terminal brain natriuretic peptide precursor (NT-proBNP) levels in the peripheral blood of patients with acute coronary syndrome (ACS) and to provide the basis for its application in the early diagnosis of ACS. A total of 440 patients admitted to the hospital for examination and treatment were enrolled, including 330 patients with ACS and 110 cases in the control group. Routine blood examination and determination of NT-proBNP in all subjects were conducted immediately at the time of admission to analyze the difference in plasma NT-proBNP between the two groups. The plasma NT-proBNP levels in ACS were significantly higher (P < 0.01) and were associated with the severity of coronary lesions. The present study indicated that the plasma NT-proBNP level in ACS patients is significantly increased and has a potential value in the early diagnosis of ACS.

Molecular phylogeny of four morphologically similar Ostorhinchus taxa with specific comments on O. cf. properuptus dotted type

In this study, the partial mtDNA 16s rRNA gene and the S7 nuclear intron were used to resolve the phylogenetic relationship of four morphologically similar members of Ostorhinchus, including two colour morphs of Ostorhinchus properuptus (lined and dotted types), Ostorhinchus cyanosoma and Ostorhinchus holotaenia. Two different tree-building methods, maximum likelihood (ML) and a Bayesian-based method, yielded trees with highly similar topologies and high bootstrap values and posterior probabilities on the main nodes. Two main clades were recovered, suggesting that O. properuptus dotted type is closely related to O. holotaenia, and O. properuptus lined type members with O. cyanosoma. In addition, the genetic distance between the dotted and lined types of O. properuptus (0·299) was 23-fold higher than that between the dotted type and O. holotaenia (0·013). The dotted type can be identified by genetics as slightly differentiated in Japanese waters. It is treated as a population of the widespread species O. holotaenia.

Salmonellosis outbreak among factory workers--Huizhou, Guangdong Province, China, July 2004

INTRODUCTION

During July 9--14, 2004, an outbreak of gastroenteritis occurred among workers at an electronics factory in Huizhou, Guangdong Province, China; 199 cases were reported. A case-control investigation was initiated to identify the agent and the mode of transmission.

METHODS

Stool samples were collected from 142 workers and food handlers and cultured for enteric pathogens. A questionnaire concerning meals and foods eaten in the factory cafeteria during July 11--13 was administered to 92 ill workers and 100 controls.

RESULTS

Of approximately 2,000 workers who worked during the outbreak, 197 (10%) had illness consistent with the case definition. Salmonella enteritidis was identified from 44 (31%) of 142 stool samples collected from ill workers. Ill workers were more likely than controls to have eaten breakfast in the factory cafeteria during July 11--13. Of eight foods served at breakfast in the factory cafeteria, three were associated with illness: cake, bread (on July 12 only), and congee (i.e., rice porridge). Stratification of bread and congee exposure by cake consumption indicated that only bread eaten on July 12 was associated with gastroenteritis. The cake was baked on July 11, and a mixture that included raw eggs was poured on top; the cake was then stored at room temperature and served for breakfast on 3 consecutive days (July 11--13). The bread was stored together with the cake on July 11 and 12. No leftover food was tested.

DISCUSSION

The investigation indicated that an outbreak of S. enterica serotype Enteritidis resulted from consumption of an unusual food vehicle (i.e., cake) that had been contaminated from a more typical source (i.e., raw eggs). The bread was stored at room temperature together with cake on which a mixture made from raw eggs had been poured. The bread was probably contaminated by contact with the cake.

CONCLUSION

Food handlers should be instructed that intact fresh eggs can harbor S. enteritidis, foods made from eggs must be cooked, and prepared food must be stored under refrigeration.

Uptake of gentamicin by bullfrog saccular hair cells in vitro

Vertebrate sensory hair cells in the inner ear are pharmacologically sensitive to aminoglycoside antibiotics. Although the ototoxicity of aminoglycosides is well known, the route of drug uptake by hair cells and mechanisms of cytotoxicity remain poorly understood. Previously published studies have documented the intracellular distribution of gentamicin using immunocytochemical, electron microscopic, and autoradiographic methods. In this article, we compare the subcellular distribution of fluorescently conjugated gentamicin (gentamicin-Texas Red, GTTR) with immunolabeled gentamicin using confocal or electron microscopy. Gentamicin (detected by postfixation immunocytochemistry) and GTTR were rapidly taken up by hair cells throughout the bullfrog saccular explant in vitro and preferentially in peripheral hair cells. Immunolabeled gentamicin and GTTR were observed at the apical membranes of hair cells, particularly in their hair bundles. GTTR was also identified within a variety of subcellular compartments within hair cells, including lysosomes, mitochondria, Golgi bodies, endoplasmic reticulum, and nuclei, and in similar structures by immunoelectron microscopy. The distributions of GTTR and immunolabeled gentamicin are largely identical and corroborate a variety of published immunocytochemical and autoradiography studies. Thus, GTTR is a valid fluorescent probe with which to investigate the pharmacokinetics and mechanisms of gentamicin accumulation.

Sesquiterpenes from the Formosan stolonifer Tubipora musica

Eight new sesquiterpenes, tubipolides A-G (1-7) and tubiporone (8) (novel carbon skeleton), and a known sesquiterpene, spirotubipolide, have been isolated from the Formosan stolonifer Tubipora musica. The structures of compounds 1-8 were determined by 1D and 2D NMR spectral analysis.

Cytochemical localization of Na+/K+-ATPase activity in cochlear strial marginal cells after various catecholamine administrations

Sodium/potassium-activated adenosine triphosphatase (Na+/K+-ATPase) activity in the kidney and brain is high, and is regulated by catecholamines. Na+/K+-ATPase activity is also high in the basolateral infoldings of the strial marginal cells, where it aids in maintaining the characteristic electrolyte composition of the endolymph. To clarify the involvement of humoral control in strial function, particularly the role of catecholamines, the K+-dependent p-nitrophenylphosphatase (K+-NPPase) activity of strial marginal cells was investigated in guinea pigs using a cerium-based cytochemical method. The effects of reserpine, serotonin (5-HT), norepinephrine (NE), epinephrine (EP), both alone and in combination, were studied. High doses of reserpine cause depletion of sympathetic substances. Strial K+-NPPase activity was decreased after reserpine or dopamine treatment, and was increased after 5-HT, NE, and EP treatment. After reserpinization, repeated treatment with 5-HT, NE, or EP led to detectable strial enzyme activity. Thus, exogenous 5-HT, NE, and EP were able to restore strial K+-NPPase activity in the reserpine-treated animals. These results suggested that biogenic amines regulate strial K+-NPPase activity. Thus, the function of the stria vascularis may be regulated by the opposing actions of these catecholamines, and 5-HT.

Junceol A, a new sesquiterpenoid from the sea pen Virgularia juncea

A new sesquiterpenoid, junceol A(1), as well as two known diterpenoids, sclerophytin A (2) and cladiellisin (3), have been isolated from the sea pen octocoral Virgularia juncea. The structure of metabolite 1 was determined by extensive spectral analysis. Compounds 1-3 have been shown to exhibit cytotoxicity toward P-388 cancer cells.

Cytotoxic dolabellane diterpenes from the Formosan soft coral Clavularia inflata

Six new cytotoxic dolabellane diterpenes, (1R,12R)-dolabella-4(16),7,10-triene-3,13-dione (1), (1R*,7R*,8S*,12R*)-dolabella-4(16),10-diene-7,8-epoxy- 3,13-dione (2), (1R*,10R*,11S*,12R*)-dolabella-4(16),7-diene-10,11-epoxy-3,13-dione (3), (1R)-dolabella-4(16),7,11(12)-triene-3,13-dione (4), (1R*,3R*)-3-hydroxydolabella-4(16),7,11(12)-triene-3,13-dione (5), and (1R*,7R*)-7-hydroperoxydolabella-4(16),8(17),11(12)-triene-3,13-dione (6), have been isolated from the Formosan soft coral Clavularia inflata. The structures of compounds 1-6 were determined by 1D and 2D spectral analysis, and their cytotoxicity against selected cancer cells was measured in vitro.

Cytotoxic cembrenolides and steroids from the formosan soft coral Sarcophyton crassocaule

Three new cytotoxic cembrenolide diterpenes, sarcocrassolide (1), crassolide (2), and 13-acetoxysarcocrassolide (3); a known cytotoxic cembrenolide, denticulatolide (4); and two cytotoxic steroids, (24S)-24-methylcholestane-3beta,5alpha,6beta-triol (5) and 24zeta-methylcholestane-3beta,5alpha,6beta,25-te traol-25-monoacetate (6), have been isolated from the Formosan soft coral Sarcophyton crassocaule. The structures of compounds 1-6 were determined by 1D and 2D spectral analysis.

[Diagnosis and treatment of sphenoid sinus cyst]

OBJECTIVE

To better understand the sphenoid sinus cyst and make correct diagnosis and treat it efficiently.

METHOD

47 patients with sphenoid sinus cyst were investigated. Presenting symptoms, radiographic appearances and treatment were analyzed, respectively.

RESULT

The present study demonstrated that the incidence of sphenoid sinus cyst had apparently increased in recent years. The most common symptom was headache, accident rate was 64%, followed by ocular disturbance, nose was involved in 15% patients. The optic nerve is the most frequently involved cranial nerve it makes decompression surgery necessary to recovery visual loss. Radiographic finding made contribution to location the lesion and exposition nature of the lesion. With the help of nasal endoscope, more information could be get to establish correct diagnosis, and operation under nasal endoscope would be safe with minimal blood loss, reduced operating time, less pains and short postoperative hospitalization.

CONCLUSION

CT, MRI and nasal endoscope provide the greatest diagnosis information and guide management, nasal endoscope plays an important role in treatment of sphenoid sinus cyst. Emergency surgery should be performed on patients with visual loss.

A cytotoxic lobane diterpene from the formosan soft coral Sinularia inelegans

A new cytotoxic lobane diterpene, ineleganene (1), was isolated from the Formosan soft coral Sinularia inelegans. The structure of compound 1 was determined by 1D and 2D spectral analysis.

Cytotoxic cembrenolide diterpenes from the formosan soft coral lobophytum crassum

A new cytotoxic cembrenolide diterpene, lobocrassolide (1), and a known cytotoxic cembrenolide, lobohedleolide (2), were isolated from the Formosan soft coral Lobophytum crassum. The structure of compound 1 was determined by 1D and 2D spectral analysis.

Parameters for the preoperative evaluation of arteriosclerosis for free-flap transfers in head and neck surgery

The microsurgical transfer of free tissue has become essential for reconstructive surgery in the head and neck, and arteriosclerosis is one of the risk factors for microvascular anastomosis. In order to detect severe arteriosclerosis and to determine the parameters useful for evaluating arteriosclerosis preoperatively, the grade of arteriosclerosis was investigated with respect to age, PWV (Aortic Pulse Wave Velocity), ocular fundus findings, and histopathological findings of the recipient arteries in 40 patients with malignant tumours. Severe arteriosclerosis was detected in 2/40 patients by the PWV, in the same 2/40 patients by the ocular fundus findings and in the same 2/40 patients by histopathological findings. The current observations indicate that the PWV and ocular fundus findings are useful parameters for the preoperative evaluation of the grade of arteriosclerosis.

Constitutive expression of GlyCAM-1 core protein in the rat cochlea

Glycosylation-dependent cell adhesion molecule-1 (GlyCAM-1) is a mucin-like glycoprotein previously identified on high endothelial venules (HEV) of lymph nodes and also in lactating mammary glands. A specifically glycosilated form of GlyCAM-1 on HEV has been shown to be a ligand for a leukocyte L-selectin, which plays an important role in leukocyte rolling along the inflamed endothelium. Here we report that GlyCAM-1 is also expressed in the cochlea. Immunohistochemistry revealed the lateral wall of the cochlea, tectorial membrane, modiolus, organ of corti, and spiral modiolar vein (SMV) to be strongly stained with polyclonal anti-GlyCAM-1 antibody. Moreover, RT-PCR of the cochlear tissue by the use of specific oligonucleotide primers for rat GlyCAM-1 generated a 378 bp product which was then verified by nucleotide sequencing to represent GlyCAM-1. Electron microscopic investigation revealed the presence of GlyCAM-1 over the entire lumenal surface of the vessels, and the basolateral infoldings in stria vascularis. However, soluble L-selectin or mAb MECA-79 which recognizes a carbohydrate epitope on functional L-selectin ligands bound only to the spiral ligament, tectorial membrane and modiolus. These observations suggest that GlyCAM-1 expressed in the cochlear region is heterogenous in terms of its glycosylation.

Study on facial motoneuronal death after proximal or distal facial nerve transection

BACKGROUND

Among the cranial nerves, the facial nerve is most liable to be damaged. Pathologic changes in the facial motor nucleus (FMN) after nerve injury are not well recognized, and the optimal time for facial nerve reconstruction after axotomy is controversial. In this study, to clarify the pathologic change in the FMN after axotomy and to determine the best time for surgery, facial motoneuronal death was investigated after facial nerve injury.

METHODS

Sixty Wistar rats were divided into proximal and distal groups. In the proximal group, the right facial nerve was transected at the porus of internal acoustic meatus. In the distal group, the nerve was cut at the stylomastoid foramen. The animals were sacrificed from day 3 to day 60 after surgery, and the brainstem was fixed with 4% paraformaldehyde. The FMN were then examined in serial sections stained with Cresyl Violet, and facial motoneurons were counted under a light microscope.

RESULTS

The death rate of facial motoneurons in the animals that underwent proximal axotomy was found to be higher and cell death occurred earlier than in the distal axotomy animals at every time point. Moreover, neuron death increased with time and peaked at 15 days after surgery.

CONCLUSIONS

The results indicate that the injury site was correlated with facial motoneuronal death, and suggest that reconstructive surgery should be performed as early as possible.

Cytotoxic terpenoids from the Formosan soft coral Nephthea brassica

Two new cytotoxic cembranoid diterpenes, brassicolide (1) and brassicolide acetate (2); a new cytotoxic sesquiterpene, (-)-4alpha-O-acetyl-selin-11-en (3); and six cytotoxic terpenoids, (-)-selin-11-en-4alpha-ol (4), 2-hydroxynephthenol (5), nephthenol (6), cembrene A (7), epoxycembrene A (8), and (-)-beta-elemene (9), have been isolated from the Formosan soft coral Nephthea brassica. The structures of compounds 1-9 were determined by spectral, chemical, and X-ray crystallographic analysis.

Cytochemical localization of ouabain-sensitive, K+-dependent p-nitrophenylphosphatase activity in the choroid plexus of normal and reserpinized guinea pigs

High doses of reserpine induce depletion of biogenic amines. The K-NPPase activity of choroid plexus was determined after one-shot reserpine administration using cerium-based cytochemistry. In normal untreated animals, reaction product was found on the microvilli of the choroidal epithelium but was almost undetectable 3 and 7 days after reserpinization. At 20 days after reserpinization, however, it was detectable. These findings suggested that reserpine decreased the choroidal Na,K-ATPase activity, and that catecholamines might be essential to maintain normal choroidal Na,K-ATPase activity. (J Histochem Cytochem 46: 975-976, 1998)

Desiccation resistance of two semiterrestrial isopods, Ligia exotica and Ligia taiwanensis (Crustacea) in Taiwan

The ability to resist desiccation stress was examined in two semiterrestrial Ligia species, Ligia exotica Roux and L. taiwanensis Lee, in Taiwan, under a certain desiccation condition. L. exotica exhibited the longer survival time, lower weight-specific rates of water loss, and the slightly higher ability of tolerance to water loss, compared to L. taiwanensis. In each species, the animal size displays a positive correlation to the survival time and total ability to resist desiccation, yet this size effects on the weight-specific water loss rate is negative. Neither water content nor maximum tolerance to water loss shows the association with the animal size in both species. The path ways and magnitudes of the interactions between these traits of desiccation resistance are analyzed and diagrammed using a stepwise regression model. In this model, the body sizes of animal can explain the most part of the variations in the survival time. The body size has a direct effect and an indirect effect, through the effect on water loss rate, on the time that the experimental animals can survival under this desiccated condition. These results suggest that L. exotica attains larger size than does L. taiwanensis, a lower transpiration rate and, consequently, a greater ability in desiccation resistance. The performances of these interactions in the desiccated resistance are more advantageous for L. exotica to migrate and colonize in variable land habitats within a certain limit, and as a result that L. exotica shows a broader distribution pattern than did L. taiwanensis in Taiwan.