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1.
Pharm Res ; 38(3): 491-501, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33666838

ABSTRACT

PURPOSE: Histidine (His) undergoes light-induced reactions such as oxidation, crosslinking and addition. These reactions are initiated by singlet oxygen (1O2) to generate His photo-oxidation products, which are subject to nucleophilic attack by a non-oxidized His residue from another protein or by nucleophilic buffer components such as Tris and His. This report aims to identify light-induced His-adducts to a monoclonal antibody (mAb-1) due to the reaction of His molecules in the buffer with the photooxidized His residues under ICH light conditions. Since polysorbate-20 (PS-20) is a commonly used excipient in biotherapeutics formulation, it is also important to study the impact of PS-20 concentration on protein photostability. RESULTS: We identified and characterized light-induced His-adducts of mAb-1 by LC-MS/MS. We showed that the levels of light-induced His-adducts generally correlate with the solvent accessibility of His residues in the protein. In addition, the presence of PS-20 at concentrations commonly used in protein drug formulations can significantly increase the levels of light-induced His-adducts. CONCLUSIONS: Since His residues are present in a conserved region in the Fc domain, and may be present in the complementarity-determining region (CDR), the impact on the biological functions of the His-adducts observed here should be further studied to evaluate the risk of their presence.


Subject(s)
Histidine/chemistry , Immunoglobulin G/chemistry , Oxidants, Photochemical/chemistry , Polysorbates/chemistry , Amino Acid Sequence , Chromatography, High Pressure Liquid , Drug Compounding , Excipients/chemistry , Oxidation-Reduction , Protein Aggregates , Protein Conformation , Protein Denaturation , Tandem Mass Spectrometry
2.
ChemMedChem ; 16(11): 1740-1743, 2021 06 07.
Article in English | MEDLINE | ID: mdl-33522135

ABSTRACT

A strategy for creating potent and pan-genotypic stimulator of interferon genes (STING) agonists is described. Locking a bioactive U-shaped conformation of cyclic dinucleotides by introducing a transannular macrocyclic bridge between the nucleic acid bases leads to a topologically novel macrocycle-bridged STING agonist (MBSA). In addition to substantially enhanced potency, the newly designed MBSAs, exemplified by clinical candidate E7766, exhibit broad pan-genotypic activity in all major human STING variants. E7766 is shown to have potent antitumor activity with long lasting immune memory response in a mouse liver metastatic tumor model. Two complementary stereoselective synthetic routes to E7766 are also described.


Subject(s)
Antineoplastic Agents/pharmacology , Interferons/agonists , Macrocyclic Compounds/pharmacology , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Screening Assays, Antitumor , Humans , Macrocyclic Compounds/chemical synthesis , Macrocyclic Compounds/chemistry , Mice , Models, Molecular , Molecular Structure , Neoplasms, Experimental/drug therapy , Neoplasms, Experimental/pathology
3.
Optom Vis Sci ; 98(1): 18-23, 2021 01 01.
Article in English | MEDLINE | ID: mdl-33394927

ABSTRACT

SIGNIFICANCE: A new device attached to a smartphone was created for objective vision screening of young children including infants and newborns. The device is compact, lightweight, portable, cost-effective, and easy to operate. Therefore, it is suitable for screening large numbers of children in clinical settings, schools, and communities. PURPOSE: This article introduces a new device attached to a smartphone for objective vision screening. It can detect and categorize significant refractive errors, anisometropia, strabismus, cloudy ocular media, and ptosis that may cause amblyopia. METHODS: The new device applies the same principles as conventional streak retinoscopy but examines both eyes simultaneously and records the results electronically. The device comprises optical elements that produce a precise streak light beam and move it across a child's both eyes. The smartphone's video camera catches and records the motion of retinal reflex inside the child's pupils. By observing the direction of motion of the retinal reflex relative to the light beam motion, as well as its speed, width, and brightness, the examiner is able to assess the individual and comparative refractive status, ocular alignment, and other conditions. RESULTS: Vision screening with this device does not require any subjective response from children. The examination can be performed and analyzed by nonprofessionals after a short learning period of time. Because the examination results are electronically recorded by the smartphone, they can be stored in the child's files and sent out for professional consultations. CONCLUSIONS: The new device will provide the same functions as conventional streak retinoscopy but examines a child's both eyes simultaneously, so that, in addition to categorizing refractive errors and assessing clarity of refractive media of the eyes, it can also detect anisometropia, strabismus, and anisocoria. In addition to showing the examination results on the smartphone's screen, the device can also store the results electronically.


Subject(s)
Equipment Design , Smartphone/instrumentation , Vision Screening/instrumentation , Amblyopia/diagnosis , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Refraction, Ocular , Refractive Errors/diagnosis , Retinoscopes , Strabismus/diagnosis
4.
Trends Ecol Evol ; 35(3): 235-244, 2020 03.
Article in English | MEDLINE | ID: mdl-31862123

ABSTRACT

Often perceived as environmentally benign, 'green' renewable energy technologies have ecological costs that are often overlooked, especially those occurring below the waterline. After briefly discussing the impacts of hydropower on freshwater and marine organisms, we focus this review on the impacts of marine renewable energy devices (MREDs) on underwater marine organisms, particularly offshore wind farms and marine energy converters (e.g., tidal turbines). We consider both cumulative impacts and synergistic interactions with other anthropogenic pressures, using offshore wind farms and the Taiwanese white dolphin (Sousa chinensis taiwanensis) as an example. While MREDs undoubtedly can help mitigate climate change, variability in the sensitivity of different species and ecosystems means that rigorous case-by-case assessments are needed to fully comprehend the consequences of MRED use.


Subject(s)
Ecosystem , Energy-Generating Resources , Aquatic Organisms , Renewable Energy , Wind
5.
Dis Aquat Organ ; 123(3): 257-262, 2017 03 21.
Article in English | MEDLINE | ID: mdl-28322212

ABSTRACT

Direct observations of the causes of injuries to cetaceans are rare events. For very small and declining populations, such events may be even less likely to be observed because of the few individuals that remain. A long-term monitoring program using photographic identification of individuals resulted in the documentation of an individual Taiwanese humpback dolphin Sousa chinensis taiwanensis that survived a harmful interaction with fishing gear. An adult female that was accompanied by a young calf sustained massive damage to several tissue types on her dorsal surface. From the injuries, it is clear that the animal had suffered intense trauma that likely caused pain for several months as the fishing gear sliced through its dorsal hump and fin. Given the incredible mutilation, the animal is likely compromised at some level and probably continues to experience ongoing pain. This case, along with observations of other individuals in this population bearing serious injuries or being entangled in fishing gear, is direct evidence that the impacts of local fisheries on this subspecies are almost certainly unsustainable.


Subject(s)
Dolphins , Endangered Species , Wounds and Injuries/veterinary , Animal Welfare , Animals , Female , Fisheries
6.
Mar Pollut Bull ; 116(1-2): 167-174, 2017 Mar 15.
Article in English | MEDLINE | ID: mdl-28065551

ABSTRACT

The Critically Endangered Taiwanese humpback dolphin (Sousa chinensis taiwanensis) is endemic to inshore and estuarine waters of central western Taiwan. It numbers fewer than 75 individuals, is declining and faces a myriad of human threats. Data from a long-term photo-identification program on these dolphins allowed major injuries to be examined quantitatively. A large proportion (57.7%) of individuals had suffered major human-induced injuries that likely compromised their health, survivorship or reproductive potential and thus, the future of this subspecies. Considering major injuries as "takes", the injury rate (1.13 dolphins/year) for the population was 8-8.5 times higher than its Potential Biological Removal rate. Observations of new injuries and fishing gear entanglements on several dolphins showed that fisheries continue to be the predominant cause of these major injuries. Unless immediate action is taken to reduce harmful fisheries, extinction is imminent for Taiwan's only endemic dolphin.


Subject(s)
Dolphins/injuries , Endangered Species , Animals , Conservation of Natural Resources , Humans , Population Dynamics
7.
Dis Aquat Organ ; 120(3): 179-87, 2016 08 09.
Article in English | MEDLINE | ID: mdl-27503913

ABSTRACT

Conspicuous vertebral column abnormalities in humpback dolphins (genus Sousa) were documented for the first time during 3 photo-identification field studies of small populations in Taiwan, Senegal and Angola. Seven Taiwanese humpback dolphins S. chinensis taiwanensis with vertebral column anomalies (lordosis, kyphosis or scoliosis) were identified, along with 2 possible cases of vertebral osteomyelitis. There was evidence from several individuals photographed over consecutive years that the anomalies became more pronounced with age. Three Atlantic humpback dolphins S. teuszii were observed with axial deviations of the vertebral column (lordosis and kyphosis). Another possible case was identified in a calf, and 2 further animals were photographed with dorsal indents potentially indicative of anomalies. Vertebral column anomalies of humpback dolphins were predominantly evident in the lumbo-caudal region, but one Atlantic humpback dolphin had an anomaly in the cervico-thoracic region. Lordosis and kyphosis occurred simultaneously in several individuals. Apart from the described anomalies, all dolphins appeared in good health and were not obviously underweight or noticeably compromised in swim speed. This study presents the first descriptions of vertebral column anomalies in the genus Sousa. The causative factors for the anomalies were unknown in every case and are potentially diverse. Whether these anomalies result in reduced fitness of individuals or populations merits attention, as both the Taiwanese and Atlantic humpback dolphin are species of high conservation concern.


Subject(s)
Dolphins , Kyphosis/veterinary , Lordosis/veterinary , Scoliosis/veterinary , Spine/abnormalities , Animals , Kyphosis/pathology , Lordosis/pathology , Scoliosis/pathology , Spine/pathology
8.
Adv Mar Biol ; 73: 91-117, 2016.
Article in English | MEDLINE | ID: mdl-26790889

ABSTRACT

The humpback dolphins of the eastern Taiwan Strait were first discovered scientifically in 2002 and since then have received much research attention. We reviewed all information published in peer-reviewed scientific journals on these dolphins and where appropriate and available, peer-reviewed scientific workshop reports and graduate theses were also examined. Recent evidence demonstrated that this population warranted recognition as a subspecies, Sousa chinensis taiwanensis. It is found in a highly restricted and linear strip of coastal waters along central western Taiwan. Numbering fewer than 80 individuals and declining, five main threats (fisheries interactions, habitat loss and degradation, loss of freshwater to estuaries within their habitat, air and water pollution, and noise) threaten the future existence of this subspecies. These dolphins have cultural and religious importance and boast the highest level of legal protection for wildlife in Taiwan. However, despite enormous efforts by local and international non-governmental groups urging immediate conservation actions, there have been no real government efforts to mitigate any existing threats; instead, some of these threats have worsened. Based on recent studies, we suggest the IUCN Red List status be revised to Critically Endangered CR 2a(ii); D for the subspecies.


Subject(s)
Conservation of Natural Resources , Dolphins/classification , Dolphins/physiology , Endangered Species , Animal Distribution , Animals , Ecosystem , Population Dynamics , Taiwan
9.
J Acoust Soc Am ; 138(5): 2829-35, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26627759

ABSTRACT

Differences in the acoustic variables of whistles emitted by Indo-Pacific humpback dolphins (Sousa chinensis) from two coastal locations along western Peninsular Malaysia were investigated. Duration, frequency, and frequency modulation variables were extracted from and used to characterize recordings of free-ranging humpback dolphins that were made using a broadband towed hydrophone. A total of 960 whistles from Matang Mangroves and 823 whistles from Langkawi Island were used in analyses. The whistles of Malaysian humpback dolphins covered frequencies from 1231 to 27 120 Hz with durations from 0.010-1.575 s. Significant multivariate differences were found in whistles emitted between locations. Significant differences were also found between dolphins of the two locations in their whistle duration, frequency modulation, and all frequency variables except for minimum frequency, which is likely under morphological constraints. The differences in whistles may be related to adaptations to the local acoustic habitat or unique whistles may have developed due to social interactions within each location, or broader scale differences resulting from geographic separation between the locations.


Subject(s)
Dolphins/physiology , Vocalization, Animal/physiology , Animals , Ecosystem , Indian Ocean , Sound Spectrography , Species Specificity
10.
Cell Rep ; 13(5): 1033-45, 2015 Nov 03.
Article in English | MEDLINE | ID: mdl-26565915

ABSTRACT

Recurrent mutations in the spliceosome are observed in several human cancers, but their functional and therapeutic significance remains elusive. SF3B1, the most frequently mutated component of the spliceosome in cancer, is involved in the recognition of the branch point sequence (BPS) during selection of the 3' splice site (ss) in RNA splicing. Here, we report that common and tumor-specific splicing aberrations are induced by SF3B1 mutations and establish aberrant 3' ss selection as the most frequent splicing defect. Strikingly, mutant SF3B1 utilizes a BPS that differs from that used by wild-type SF3B1 and requires the canonical 3' ss to enable aberrant splicing during the second step. Approximately 50% of the aberrantly spliced mRNAs are subjected to nonsense-mediated decay resulting in downregulation of gene and protein expression. These findings ascribe functional significance to the consequences of SF3B1 mutations in cancer.


Subject(s)
Alternative Splicing , Mutation , Neoplasms/genetics , Phosphoproteins/genetics , Ribonucleoprotein, U2 Small Nuclear/genetics , Alleles , Amino Acid Sequence , Base Sequence , HEK293 Cells , Humans , Molecular Sequence Data , Mutation Rate , Nonsense Mediated mRNA Decay , Phosphoproteins/chemistry , Phosphoproteins/metabolism , RNA Splicing Factors , Ribonucleoprotein, U2 Small Nuclear/chemistry , Ribonucleoprotein, U2 Small Nuclear/metabolism
11.
Zool Stud ; 54: e36, 2015.
Article in English | MEDLINE | ID: mdl-31966123

ABSTRACT

BACKGROUND: Subspecies recognition can affect how people (scientists and non-scientists alike) view organisms and thus has important implications for research on, as well as the conservation of, these entities. Recently, a small group of Indo-Pacific humpback dolphins was discovered inhabiting the waters off central western Taiwan. This geographically isolated population possesses pigmentation patterns that are subtly, but noticeably, different from their nearest conspecifics in the neighbouring waters of the Jiulong River Estuary and Pearl River Estuary of mainland China. Due to this population's low and declining numbers and the numerous threats it faces, it was assessed as critically endangered by the Red List of Threatened Species of the International Union for Conservation of Nature. The purpose of this study is to examine the degree of differentiation of the Taiwanese population to determine if subspecies recognition iswarranted. RESULTS: Analysis of the degree of differentiation in pigmentation patterns revealed nearly non-overlapping distributions between dolphins from Taiwanese waters and those from the Jiulong River + Pearl River estuaries of mainland China (the nearest known populations). The Taiwanese dolphins were clearly diagnosable from those of the Jiulong River + Pearl Riverestuaries under the most commonly accepted '75%rule' for subspecies delimitation (with 94% of one group being separable from 99+% of the other). Evidence of geographical isolation and behavioural differences also provided additional support for the distinctiveness of the Taiwanese dolphins. CONCLUSIONS: Together, the evidence strongly demonstrated that the Taiwanese humpback dolphin population is differentiated at the subspecies level and on an evolutionary trajectory that is independent from that of dolphins from adjacent waters of mainland China (i.e. Jiulong River + Pearl River estuaries). As a result, the taxonomy of Sousa chinensis was revised to include two subspecies: the Taiwanese humpback dolphin, Sousa chinensis taiwanensis subsp. nov., and the Chinese humpback dolphin, Sousa chinensis chinensis (the nominotypical subspecies). These subspecies are described, and the holotype and paratype specimens for S. c. taiwanensis are established.

12.
AAPS PharmSciTech ; 10(2): 678-83, 2009.
Article in English | MEDLINE | ID: mdl-19459051

ABSTRACT

Methylcellulose and hydroxypropylmethylcellulose (hypromellose) are used in topical formulations of a protein to form a viscous hydrogel. Five lots of hypromellose raw material were made into 3% gel; all showed viscosity loss after sterilization by autoclave. EDTA (edetate disodium) minimized the viscosity loss caused by autoclaving in the presence of up to 100 ppm H(2)O(2). These results suggest that EDTA may prevent loss of viscosity of the hydrogel when peroxide is present. H(2)O(2) at low levels (2-50 ppm) caused significant viscosity loss over time at either 40 degrees C or 5 degrees C in 3% methylcellulose or hypromellose gel. EDTA slowed the rate of viscosity loss during storage under stress by H(2)O(2) but did not completely prevent the loss. Methionine was effective in completely preventing gel-viscosity loss during storage in the presence of up to 50 ppm H(2)O(2). On the basis of these results, it is recommended that methionine be added to the protein topical formulation as a stabilizer against viscosity loss.


Subject(s)
Edetic Acid/pharmacology , Hydrogel, Polyethylene Glycol Dimethacrylate/chemistry , Methionine/pharmacology , Methylcellulose/analogs & derivatives , Methylcellulose/chemistry , Hydrogen Peroxide/chemistry , Hypromellose Derivatives , Sterilization , Temperature , Viscosity
13.
Cerebrovasc Dis ; 21(1-2): 67-73, 2006.
Article in English | MEDLINE | ID: mdl-16330866

ABSTRACT

BACKGROUND: Adhesion molecules play important roles in the pathophysiology of ischemic stroke. The aim of the present study was to investigate whether serum levels of soluble intercellular adhesion molecule 1 (sICAM-1), soluble vascular cellular adhesion molecule 1 (sVCAM-1) and soluble E-selectin were associated with neurological deterioration of ischemic stroke. METHODS: 238 consecutive patients with ischemic stroke examined within 24 h from onset were enrolled into the study. The stroke severity was daily assessed with the NIH Stroke Scale (NIHSS) within the first week after admission. Serum levels of sICAM-1, sVCAM-1 and sE-selectin after admission were measured using enzyme-linked immunosorbent assay. Multivariate logistic regression was used to analyze the association of serum levels of sICAM-1, sVCAM-1 and sE-selectin on admission with the neurological deterioration of ischemic stroke, adjusted for potential confounders. RESULTS: 52 (21.8%) out of 238 stroke patients suffered from neurological deterioration. Serum levels of sICAM-1 on admission of stroke patients were significantly higher than those of healthy controls. Compared with patients without deterioration, patients with neurological deterioration had higher levels of sICAM-1, but not of sVCAM-1 and sE-selectin. On multivariate logistic regression, the serum level of sICAM-1 on admission was associated with neurological deterioration of stroke (OR 2.92, 95% CI 1.41-6.05). Other variables associated with neurological deterioration were fasting serum glucose (OR 1.65, 95% CI 1.24-2.20), baseline fibrinogen (OR 1.31, 95% CI 1.13-1.52) and NIHSS score (OR 1.23, 95% CI 1.15-1.32). CONCLUSIONS: The serum level of sICAM-1 on admission is associated with neurological deterioration of ischemic stroke.


Subject(s)
Brain Ischemia/blood , E-Selectin/blood , Intercellular Adhesion Molecule-1/blood , Stroke/blood , Vascular Cell Adhesion Molecule-1/blood , Aged , Aged, 80 and over , Brain Ischemia/complications , Brain Ischemia/therapy , Case-Control Studies , China , Cohort Studies , Female , Hospitalization , Humans , Male , Middle Aged , Severity of Illness Index , Stroke/etiology , Stroke/therapy , Treatment Outcome
14.
Neuroepidemiology ; 24(1-2): 87-95, 2005.
Article in English | MEDLINE | ID: mdl-15459515

ABSTRACT

BACKGROUND: Frequency of poststroke cognitive impairment is high in western countries, and the risk factors of poststroke cognitive impairment have not been fully understood yet. We sought to examine the frequency and risk factors of cognitive impairment after ischemic stroke in a large stroke cohort of China. METHODS: A total of 434 consecutive patients with ischemic stroke were enrolled. The cognitive status before and 3 months after stroke was evaluated using the Informant Questionnaire on Cognitive Decline in the Elderly and the Mini-Mental State Examination, respectively. Poststroke cognitive impairment was defined as cognitive impairment with concomitant stroke, stroke-related cognitive impairment was defined as cognitive impairment developing after index stroke, and cognitive impairment after first-ever stroke was defined as cognitive impairment developing after first-ever stroke. Logistic regression analysis was used to find the risk factors of cognitive impairment after stroke. RESULTS: (1) Frequency of poststroke cognitive impairment was 37.1%, that of stroke-related cognitive impairment was 32.2%, and that of cognitive impairment after first-ever stroke was 29.6%. (2) The patients with cognitive impairment more often had older age, low educational level, atrial fibrillation, prior stroke, everyday drinking, left carotid territory infarction, multiple lesions, embolism, and dysphasia. (3) The factors associated with poststroke cognitive impairment in logistic regression analysis were age (OR 1.215, 95% CI 1.163-1.268), low educational level (OR 2.023, 95% CI 1.171-3.494), prior stroke (OR 5.130, 95% CI 2.875-9.157), everyday drinking (OR 2.013, 95% CI 1.123-3.607), dysphasia (OR 3.994, 95% CI 1.749-9.120), and left carotid territory infarction (OR 2.685, 95% CI 1.595-4.521). CONCLUSIONS: Cognitive impairment is common 3 months after ischemic stroke in Chinese people. Risk factors for poststroke cognitive impairment include age, low educational level, everyday drinking, prior stroke, dysphasia, and left carotid territory infarction.


Subject(s)
Brain Ischemia/complications , Brain Ischemia/epidemiology , Cognition Disorders/epidemiology , Cognition Disorders/etiology , Stroke/complications , Stroke/epidemiology , Aged , Cerebrovascular Disorders/complications , Cerebrovascular Disorders/epidemiology , China/epidemiology , Cohort Studies , Female , Humans , Logistic Models , Male , Neuropsychological Tests , Risk Factors , Urban Population
15.
J Neurol ; 251(4): 421-7, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15083286

ABSTRACT

OBJECTIVE: We studied a large hospitalized cohort of patients aged 55 years and over with acute ischemic stroke to identify the frequency and predictors of poststroke dementia. METHODS: A total of 434 consecutive patients with ischemic stroke were enrolled in this study. During admission, the demographic data, vascular risk factors, stroke features, and neurological status information were collected. All subjects were examined by a battery of neuropsychological tests during admission and 3 months after stroke. Logistic regression analysis was used to find the predictors of poststroke dementia. RESULTS: (1) The frequency of poststroke dementia was 27.2%, that of stroke-related dementia was 21.6%, and that of dementia after first-ever stroke was 22.7% 3 months after stroke. (2) Univariate analysis indicated that older age, low educational level (

Subject(s)
Brain Ischemia/epidemiology , Dementia, Vascular/epidemiology , Stroke/epidemiology , Aged , Aged, 80 and over , Brain Ischemia/complications , Brain Ischemia/pathology , Chi-Square Distribution , China/epidemiology , Cohort Studies , Confidence Intervals , Dementia, Vascular/etiology , Dementia, Vascular/pathology , Female , Follow-Up Studies , Humans , Logistic Models , Male , Middle Aged , Odds Ratio , Predictive Value of Tests , Socioeconomic Factors , Stroke/complications , Stroke/pathology
16.
J Parasitol ; 89(5): 1071-3, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14627163

ABSTRACT

Four of the 27 Pacific sleeper sharks (Somniosus pacificus Bigelow and Schroeder) captured in the western North Pacific Ocean off eastern Taiwan between 19 March and 18 May 2002 hosted the parasitic copepod Dinemoura ferox (Krøyer, 1838) on their body surface including the fins. This report documents a new host record as well as a new ocean record for D. ferox, which until now has only been reported from the benthopelagic sharks, Somniosus microcephalus (Bloch and Schneider) and Centrophorus squamosus (Bonnaterre), occurring in the north Atlantic Ocean off Greenland and Iceland.


Subject(s)
Copepoda/physiology , Ectoparasitic Infestations/veterinary , Fish Diseases/parasitology , Sharks/parasitology , Animals , Copepoda/anatomy & histology , Copepoda/classification , Ectoparasitic Infestations/parasitology , Female , Male , Pacific Ocean , Taiwan
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