Anti-oxidative, anti-apoptotic, and anti-inflammatory activities of Connarus semidecandrus Jack ethanol extract in UVB-irradiated human keratinocytes

ETHNOPHARMACOLOGICAL RELEVANCE

Connarus semidecandrus Jack (Family: connaraceae) is a medicinal plant known for its wide distribution throughout Southeast Asia. Renowned for its diverse therapeutic properties, it has been traditionally used for treating fever, skin irritation, and colic.

AIM OF THE STUDY

Numerous individuals suffer from skin issues, including wrinkles, hyperpigmentation, and inflammation, due to environmental factors. Although many drugs are available to treat skin problems, chemical drugs have many shortcomings and side effects. Therefore, natural products are attractive potential medicines for alleviating skin troubles. We recently showed that Connarus semidecandrus Jack ethanol extract (Cs-EE) has anti-alopecia potential. This paper aims to explore the potential skin-protective effects and underlying molecular mechanisms of Connarus semidecandrus Jack in UVB-induced human keratinocytes (HaCaT).

MATERIALS AND METHODS

Before utilization, Cs-EE was dissolved in dimethyl sulfoxide (DMSO) and was preserved at a temperature of -20 °C. The phytochemical constituents of Cs-EE were detected by gas chromatography-mass spectrometry analysis (GC-MS). Sequentially, HaCaT cells were exposed to varying concentrations of Cs-EE prior to ultraviolet B (UVB) irradiation. Evaluations of cellular responses in HaCaT cells, including assessments of cell viability, deoxyribonucleic acid (DNA) damage, and gene and protein expressions, were carried out. To explore the specific signaling pathway involved, we conducted a luciferase assay in addition to validating these pathways using Western blot analysis.

RESULTS

Nitric oxide (NO) and intracellular reactive oxygen species were decreased. Melanin production through the activation of melanocytes by α-melanocyte-stimulating hormone (MSH) was also inhibited by Cs-EE. Furthermore, the mRNA expression levels of key factors such as cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), MMP-1, MMP-3, and MMP-9 exhibited a remarkable decrease. In addition, the phosphorylation of TAK1 within the signaling cascade exhibited a decline, and the activities of the transcription factor AP-1 were decreased according to a luciferase reporter assay.

CONCLUSIONS

Taken together, these findings suggest that the anti-inflammatory, anti-aging, and anti-apoptotic effects of Cs-EE indicate the compound's potential usefulness as a natural component in pharmaceutical and cosmetic products.

Convolutional Neural Network to Stratify the Malignancy Risk of Thyroid Nodules: Diagnostic Performance Compared with the American College of Radiology Thyroid Imaging Reporting and Data System Implemented by Experienced Radiologists

BACKGROUND AND PURPOSE

Comparison of the diagnostic performance for thyroid cancer on ultrasound between a convolutional neural network and visual assessment by radiologists has been inconsistent. Thus, we aimed to evaluate the diagnostic performance of the convolutional neural network compared with the American College of Radiology Thyroid Imaging Reporting and Data System (TI-RADS) for the diagnosis of thyroid cancer using ultrasound images.

MATERIALS AND METHODS

From March 2019 to September 2019, seven hundred sixty thyroid nodules (≥10 mm) in 757 patients were diagnosed as benign or malignant through fine-needle aspiration, core needle biopsy, or an operation. Experienced radiologists assessed the sonographic descriptors of the nodules, and 1 of 5 American College of Radiology TI-RADS categories was assigned. The convolutional neural network provided malignancy risk percentages for nodules based on sonographic images. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were calculated with cutoff values using the Youden index and compared between the convolutional neural network and the American College of Radiology TI-RADS. Areas under the receiver operating characteristic curve were also compared.

RESULTS

Of 760 nodules, 176 (23.2%) were malignant. At an optimal threshold derived from the Youden index, sensitivity and negative predictive values were higher with the convolutional neural network than with the American College of Radiology TI-RADS (81.8% versus 73.9%, P = .009; 94.0% versus 92.2%, P = .046). Specificity, accuracy, and positive predictive values were lower with the convolutional neural network than with the American College of Radiology TI-RADS (86.1% versus 93.7%, P < .001; 85.1% versus 89.1%, P = .003; and 64.0% versus 77.8%, P < .001). The area under the curve of the convolutional neural network was higher than that of the American College of Radiology TI-RADS (0.917 versus 0.891, P = .017).

CONCLUSIONS

The convolutional neural network provided diagnostic performance comparable with that of the American College of Radiology TI-RADS categories assigned by experienced radiologists.

Untargeted Metabolomics Toward Systematic Characterization of Antioxidant Compounds in Betulaceae Family Plant Extracts

Plant species have traditionally been revered for their unparalleled pharmacognostic applications. We outline a non-iterative multi-parallel metabolomic-cum-bioassay-guided methodology toward the functional characterization of ethanol extracts from the Betulaceae family plants (n = 10). We performed mass spectrometry (MS)-based multivariate analyses and bioassay-guided (ABTS antioxidant activity and cytoprotective effects against H₂O₂-induced cell damage) analyses of SPE fractions. A clearly distinct metabolomic pattern coupled with significantly higher bioactivities was observed for 40% methanol SPE eluate. Further, the 40% SPE eluate was subjected to preparative high-performance liquid chromatography (prep-HPLC) analysis, yielding 72 sub-fractions (1 min⁻¹), with the highest antioxidant activities observed for the 15 min and 31 min sub-fractions. We simultaneously performed hyphenated-MS-based metabolite characterization of bioactive components for both the 40% methanol SPE fraction and its prep-HPLC sub-fraction (15 min and 31 min). Altogether, 19 candidate metabolites were mainly observed to contribute toward the observed bioactivities. In particular, ethyl gallate was mainly observed to affect the antioxidant activities of SPE and prep-HPLC fractions of Alnus firma extracts. We propose an integrated metabolomic-cum-bioassay-guided approach for the expeditious selection and characterization of discriminant metabolites with desired phenotypes or bioactivities.

Evaluation of Antioxidant and Antimicrobial Activities of Ethanol Extracts of Three Kinds of Strawberries

The antioxidant and antimicrobial activities of three kinds of strawberry ethanol extracts from Robus corchorifolius L. f. (RCL), Rubus parvifolius L. var. parvifolius (RPL), and Duchesnea chrysantha Miq. (DCM) were investigated. The RPL was highest (P<0.05) in phenolic, flavonoid, and anthocyanin contents. 2,2-Diphenyl-1-picrylhydrazyl and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging activities of RPL and DCM extracts were higher than that of RCL (P<0.05). Hydrogen peroxide scavenging activity of RPL was high compared to DCM and RCL (P<0.05). RCL exhibited a significant (P<0.05) potent antioxidant activity in nitric oxide radical inhibition. Inhibition diameter zone (nearest mm) of extracts against the test bacteria ranged from 11.5 in RCL to 12.5 in DCM against Staphylococcus aureus, from 10.5 in RCL to 13.5 in DCM against Streptococcus pneumoniae, from 8.5 in DCM to 10.5 in RCL against Escherichia coli, and the same inhibition of 10 mm in three of the extracts against Klebsiella pneumoniae. However, there was no inhibition against fungi Aspergillus niger and Candida albicans. Three of the extracts had the same minimum inhibitory concentration values of 12.50, 12.50, and 6.25 μg/mL against S. aureus, K. pneumoniae, and S. pneumoniae, respectively. On the other hand, MIC values of 12.50, 12.50, and 6.50 μg/mL were recorded for RPL, DCM, and RCL against E. coli, respectively. The result of present study revealed that extracts from three kinds of strawberries could be potential candidates as antioxidant and antimicrobial sources for functional food industries.

Metabolite fingerprinting, pathway analyses, and bioactivity correlations for plant species belonging to the Cornaceae, Fabaceae, and Rosaceae families

A multi-parallel approach gauging the mass spectrometry-based metabolite fingerprinting coupled with bioactivity and pathway evaluations could serve as an efficacious tool for inferring plant taxonomic orders. Thirty-four species from three plant families, namely Cornaceae (7), Fabaceae (9), and Rosaceae (18) were subjected to metabolite profiling using gas chromatography-time-of-flight-mass spectrometry (GC-TOF-MS) and ultrahigh performance liquid chromatography-linear trap quadrupole-ion trap-mass spectrometry (UHPLC-LTQ-IT-MS/MS), followed by multivariate analyses to determine the metabolites characteristic of these families. The partial least squares discriminant analysis (PLS-DA) revealed the distinct clustering pattern of metabolites for each family. The pathway analysis further highlighted the relatively higher proportions of flavonols and ellagitannins in the Cornaceae family than in the other two families. Higher levels of phenolic acids and flavan-3-ols were observed among species from the Rosaceae family, while amino acids, flavones, and isoflavones were more abundant among the Fabaceae family members. The antioxidant activities of plant extracts were measured using ABTS, DPPH, and FRAP assays, and indicated that extracts from the Rosaceae family had the highest activity, followed by those from Cornaceae and Fabaceae. The correlation map analysis positively links the proportional concentration of metabolites with their relative antioxidant activities, particularly in Cornaceae and Rosaceae. This work highlights the pre-eminence of the multi-parallel approach involving metabolite profiling and bioactivity evaluations coupled with metabolic pathways as an efficient methodology for the evaluation of plant phylogenies.

Development of an Ergonomics Checklist for Investigation of Work-Related Whole-Body Disorders in Farming - AWBA: Agricultural Whole-Body Assessment

Researchers have been using various ergonomic tools to study occupational musculoskeletal diseases in industrial contexts. However, in agricultural work, where the work environment is poorer and the socio-psychological stress is high due to the high labor intensities of the industry, current research efforts have been scarce, and the number of available tools is small. In our preliminary studies, which focused on a limited number of body parts and other working elements, we developed separate evaluation tools for the upper and lower extremities. The current study was conducted to develop a whole-body ergonomic assessment tool for agricultural work that integrates the existing assessment tools for lower and upper extremities developed in the preliminary studies and to verify the relevance of the integrated assessment tool. To verify the relevance of the Agricultural Whole-Body Assessment (AWBA) tool, we selected 50 different postures that occur frequently in agricultural work. Our results showed that the AWBA-determined risk levels were similar to the subjective risk levels determined by experts. In addition, as the risk level increased, the average risk level increased to a similar extent. Moreover, the differences in risk levels between the AWBA and expert assessments were mostly smaller than the differences in risk levels between other assessment tools and the expert assessments in this study. In conclusion, the AWBA tool developed in this study was demonstrated to be appropriate for use as a tool for assessing various postures commonly assumed in agricultural work. Moreover, we believe that our verification of the assessment tools will contribute to the enhancement of the quality of activities designed to prevent and control work-related musculoskeletal diseases in other industries.

Combined mass spectrometry-based metabolite profiling of different pigmented rice (Oryza sativa L.) seeds and correlation with antioxidant activities

Nine varieties of pigmented rice (Oryza sativa L.) seeds that were black, red, or white were used to perform metabolite profiling by using ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and gas chromatography (GC) TOF-MS, to measure antioxidant activities. Clear grouping patterns determined by the color of the rice seeds were identified in principle component analysis (PCA) derived from UPLC-Q-TOF-MS. Cyanidin-3-glucoside, peonidin-3-glucoside, proanthocyanidin dimer, proanthocyanidin trimer, apigenin-6-C-glugosyl-8-C-arabiboside, tricin-O-rhamnoside-O-hexoside, and lipids were identified as significantly different secondary metabolites. In PCA score plots derived from GC-TOF-MS, Jakwangdo (JKD) and Ilpoom (IP) species were discriminated from the other rice seeds by PC1 and PC2. Valine, phenylalanine, adenosine, pyruvate, nicotinic acid, succinic acid, maleic acid, malonic acid, gluconic acid, xylose, fructose, glucose, maltose, and myo-inositol were significantly different primary metabolites in JKD species, while GABA, asparagine, xylitol, and sucrose were significantly distributed in IP species. Analysis of antioxidant activities revealed that black and red rice seeds had higher activity than white rice seeds. Cyanidin-3-glucoside, peonidin-3-glucoside, proanthocyanidin dimers, proanthocyanidin trimers, and catechin were highly correlated with antioxidant activities, and were more plentiful in black and red rice seeds. These results are expected to provide valuable information that could help improve and develop rice-breeding techniques.

In search of dialogue and discourse in applied clinical informatics

We present a model of applied clinical informatics in the context of medical informatics in general, across the domain of health sciences and the continuum of information technology development and its adoption into workflow. The distinct challenges of applied clinical informatics present an opportunity to improve efforts through collaboration of the growing number of physicians, health institutional leaders and other health workers in successfully implementing working systems. This journal will be a forum for discussion regarding approaches to design, implement, deploy and evaluate systems and importantly, how to present experiences in a way to maximize sharing of those experiences.

Challenges in reusing transactional data for daily documentation in neonatal intensive care

The reuse of transactional data for clinical documentation requires navigation of computational, institutional and adaptive barriers. We describe organizational and technical issues in developing and deploying a daily progress note tool in a tertiary neonatal intensive care unit that reuses and aggregates data from a commercial integrated clinical information system.

Application of a Medical Text Indexer to an online dermatology atlas

Clinical dermatology cases are presented as images and semi-structured text describing skin lesions and their relationships to disease. Metadata assignment to such cases is hampered by lack of a standardized dermatology vocabulary and facilitated methods for indexing legacy collections. In this pilot study descriptive clinical text from Dermatlas, a Web-based repository of dermatology cases, was indexed to Medical Subject Heading (MeSH) terms using the National Library of Medicine's Medical Text Indexer (MTI). The MTI is an automated text processing system that derives ranked lists of MeSH terms to describe the content of medical journal citations using knowledge from the Unified Medical Language System (UMLS) and from MEDLINE. For a representative, random sample of 50 Dermatlas cases, the MTI frequently derived MeSH indexing terms that matched expert-assigned terms for Diagnoses (88%), Lesion Types (72%), and Patient Characteristics (Gender and Age Groups, 62% and 84% respectively). This pilot demonstrates the potential for extending the MTI to automate indexing of clinical case presentations and for using MeSH to describe aspects of clinical dermatology.

Reducing the paper load: computer-based patient records

Physicians burdened with increasing paper work may find relief in computer-based patient records (CPR). CPRs may aid clinicians in the areas of billing, documentation, reporting, and data retrieval. Value-added features like decision support and event monitoring facilitate patient outcome, decrease health care costs and allow improved administration. The authors discuss obstacles in the use of computers in patient care with a focus on security, confidentiality, and Y2K.

Restricted natural language processing for case simulation tools

For Interactive Patient II, a multimedia case simulation designed to improve history-taking skills, we created a new natural language interface called GRASP (General Recognition and Analysis of Sentences and Phrases) that allows students to interact with the program at a higher level of realism. Requirements included the ability to handle ambiguous word senses and to match user questions/queries to unique Canonical Phrases, which are used to identify case findings in our knowledge database. In a simulation of fifty user queries, some of which contained ambiguous words, this tool was 96% accurate in identifying concepts.

Molecular biological characterization of enterovirus variant isolated from patients with aseptic meningitis

In Korea, there was a big outbreak of aseptic meningitis in 1993. Six clinical isolates of enterovirus were obtained from patients with aseptic meningitis and were identified as echovirus type 9 by serotyping with a pool of neutralizing antisera. For molecular characterization of the isolates, the nucleotide sequences of 5'-noncoding region (NCR), VP4, VP2, VP1, 2A and 2C regions of the isolates were compared with the corresponding regions of echovirus type 9 Hill and Barty strains. Unlike Hill strain, Barty strain contained a C-terminal extension to the capsid protein VP1 with an RGD (argnine-glycine-aspartic acid) motif. To determine whether similar structural features were present in our isolates, their nucleotide sequences including the VP1 region were analyzed. All isolates exhibited the VP1 extension with the RGD motif. We concluded the Korean isolates in the year of 1993 as the echovirus type 9 Barty strain although the isolates showed 15-20% nucleotide sequence differences in the several genomic regions.

Rapid subgrouping of nonpolio enterovirus associated with Aseptic Meningitis by RFLP (Restriction Fragment Length Polymorphism) assay

In Korea, there was a big outbreak of Aseptic Meningitis due to enterovirus infection in 1993. Since virus isolation and neutralizing tests are too laborious and time-consuming for the detection of enterovirus from clinical specimen, we have developed a new molecular identification method for rapid subgrouping of isolates from patients with aseptic meningitis. For the rapid subgrouping of isolates, RT-PCR (Reverse Transcription-Polymerase Chain Reaction) and RFLP (Restriction Fragment Length Polymorphism) assays were used. We have selected two oligonucleotide primers from the conserved 5'-UTR/VP2 and VP1 regions. A 652 bp (base pair) product was amplified from the 5'-UTR/VP2 region of reference viruses and the isolates. For the subgrouping of the isolates by RFLP assay, we have used 12 reference viruses (Echovirus, E6, E9, E11, E12, Coxsackievirus, CB1, CB3, CB4, CB5, Coxsackievirus, CA9, CA16, CA21, CA24), which are the common viral agents associated with aseptic meningitis. By using subgroup-specific restriction enzymes BsmAI, , HinP1I, and PleI, the isolates were classified into Echovirus subgroups. We have also shown that subgrouping of the isolates by RFLP assay based on the VP1 region is possible.

Utilization of a paediatric link collection by health professionals and laypersons

The Internet is an evolving resource for health-care information. However little information exists on providers' and other web patrons' usage of the 'medical' Internet. This study aims to characterize the users of a large paediatric link collection, describe their objectives and track their use of the information provided by the site. We utilized a paediatric link collection called the Pediatric Points of Interest (POI) and a combination of a questionnaire, unique user identifier and link-tracking system to collect data about POI patrons' demographics and Internet resource utilization. During a five week period, 5216 individuals visited the POI and requested 36,187 links. The majority of users had less than one year of Internet experience and were first-time visitors to the POI. More than 83% of users were from North America. Medical professionals were more likely to return to the POI during the study period and reported visiting the POI mainly for 'medical education', 'research', 'resource identification', and 'disease specific information'; they proceeded primarily to the resource categories 'Medical Institutions and Agencies' (32%) and 'Professional Education and Resources' (28%). Laypersons expressed the greatest interest in 'disease specific information' and 'patient education' and most frequently visited the category. 'Patient Education' (42%). On average, users were able to identify resources related to their stated goals within one level of searching. Health care providers and other web patrons are actively utilizing Internet sites to seek medical information and are able to identify resources with a minimum of searching.

Nucleotide sequencing of a part of the 5'-noncoding region of echovirus type 9 and rapid virus detection during the acute phase of aseptic meningitis

A part of the 5'-noncoding region of echovirus type 9 isolates was sequenced, and an attempt was made for rapid virus detection in clinical samples obtained from 22 subjects hospitalized with aseptic meningitis. The sequence identity of 440-bp products amplified from the region by RT-PCR was 87.7% between the standard echovirus type 9(Hill strain) and the isolates. Specific IgM antibodies to Hill strain were positive in 45.5% by immunofluorescent antibody staining of virus-infected cells. A high detection rate of PCR products was observed in cerebrospinal fluids (CSFs; 54.5%) at admission, and in peripheral mononuclear cells (PMCs; 72.7%) at the end of hospitalization. Viral genomes were detectable for 2 days in serum samples, and for 6 days in PMC samples after onset of disease. When specific IgM antibody titers were less than 1:40, the amplification rate of viral genome from serum samples was 50.0%. These results indicate that the combination of specific IgM determination and viral genome amplification from CSFs will be a rapid and reliable method for early diagnosis.

Genomic characterization of M and S RNA segments of hantaviruses isolated from bats

Genomic analysis of three Hantaan-like virus isolates from bats was performed. Cleavage patterns of reverse transcription (RT)-polymerase chain reaction (PCR) products and nucleotide sequences of G2 region of M RNA segment and N protein region of S RNA segment of the isolates were compared to that of Hantaan 76-118 strain. Genomic characteristics of the bat isolates were identical to that of Hantaan virus.

A new natural reservoir of hantavirus: isolation of hantaviruses from lung tissues of bats

Two species of bats were confirmed as new natural reservoirs of hantavirus. Antibodies to Hantaan virus were detected in 3.40% (23 of 677) of bats captured from 1989 to 1992 in Korea by the IFA technique. Areal distribution of immunofluorescent antibody were different, and seropositive rates were much high in sera of bats captured in summer (3.82%) and winter (5.82%). Viral antigens were observed in the lungs (3 of 16) and kidney (1 of 7). Two hantaviruses were isolated from lung tissues of E. serotinus and R. ferrum-equinum through a cell culture system, designated CUMC-92B8 and -92B48, respectively. Using Rous associated virus-2 reverse transcriptase-directed PCR and 2 oligonucleotide primer pairs, genomic sequences of the isolates were amplified. Amplified products of the isolates and reactivities to monoclonal antibodies very closely resembled those of Hantaan virus. These data suggest that the serotype of the isolates is closely related to Hantaan virus, and bats serve as reservoirs of hantavirus.

Variability of the surgical anatomy of the neurovascular complex of the cerebellopontine angle

The variability of the anatomic relationship of the anterior inferior cerebellar artery (AICA) to the facial (seventh) and vestibulocochlear (eighth) nerves was studied in 52 cerebellopontine angles (CPAs) from 26 adult cadavers. The AICA originated from the basilar artery (98.1%) or from the vertebral artery (1.9%) as a single (92.3% of CPAs) or duplicate (7.7%) artery. Each of the 52 CPAs had one or more arterial trunks that coursed in close proximity to the seventh and eighth cranial nerves and thus were said to be nerve-related. The nerve-related arterial trunks were divided into three segments based on their relationship to the nerves and meatus: the premeatal, meatal, and postmeatal segments. The nerve-related branches of the AICA gave rise to the internal auditory artery in 92.3% of the CPAs, the recurrent perforating artery in 78.8%, and the subarcuate artery in 30.8%. The importance of understanding the surgical anatomy of the neurovascular complex of the CPA when performing a vestibular neurectomy is reviewed.

RFLP analysis of HLA-DR beta and -DQ beta genes in the Korean patients with insulin-dependent diabetes mellitus

Human genomic DNA samples from 19 Korean patients and 31 controls of known serological DR antigen specificity were studied for insulin-dependent diabetes mellitus (IDDM)-associated variation in HLA-DR beta and -DQ beta restriction fragment length polymorphisms (RFLPs). Genotyping allowed for accurate assignment of HLA-DR types. For HLA-DRw6, a 12kb/DR beta/Taq I fragment was decreased in Korean IDDM (p less than 0.05). However, we could not find an increased frequency of a 12kb/DQ beta/Bam HI fragment or decreased frequency of a 3.7kb/DQ beta/Bam HI fragment in Korean IDDM. These results suggest a possible protective role of the HLA-DRw6 specificity in IDDM, irrespective of ethnic background, the absence of a specific DQ beta RFLP pattern associated with IDDM in Koreans, and the difference of the Korean population in the genetic of IDDM, compared to the Caucasoid population.

Magnetic control for the vocal cord adduction in the canine

An entirely satisfactory and physiologic solution to adduct paralyzed vocal cord during phonation, coughing, and swallowing has not yet been achieved. The authors noticed that velopharyngeal closure takes place simultaneously with adduction of vocal cords in order to perform phonation, coughing, and swallowing. We devised a new laryngeal pacing system to adduct the paralyzed vocal cord, utilizing velopharyngeal closure under magnetic control. Two mongrel dogs were anesthetized and the interior of the larynx was exposed using a Lynch suspension laryngoscope. A small magnet wrapped by thin Silastic was inserted into the nasal side of the soft palate via a small incision. After making a vertical midline neck incision, the pharynx was dissected and the Gaussmeter probe was inserted into the retropharyngeal space. The Gaussmeter probe was connected to the Gaussmeter and finally to the pacemaker. Electrodes were inserted into the paralyzed adductor laryngeal intrinsic muscles via punctures of the cricothyroid membrane. When the pacing system operated, arbitrarily elevated soft palate to the posterior pharyngeal wall brought about an abrupt increase in magnetic force and thus obvious adduction of the paralyzed vocal cords could be seen.

Laryngeal pacemaker using a temperature sensor in the canine

With the use of a temperature sensor that would detect temperature changes during the respiratory cycle in the pharynx, electrical stimulation of the posterior cricoarytenoid muscle was achieved in dogs whose recurrent laryngeal nerves were artificially paralyzed. Due to the temperature difference between inspiratory and expiratory air flow, a trigger pulse was generated at the beginning of inspiration. The stimulation pulse following the trigger pulse stimulated the electrodes inserted into the posterior cricoarytenoid muscles. In all five canines, obvious abduction of the vocal folds synchronized with inspiration was observed during electrical pacing.

HLA and insulin-dependent diabetes mellitus in Koreans

Specific allelic associations vary among ethnic groups. We studied the distribution of HLA-A, -B, -C and -DR antigens in 41 patients with insulin-dependent diabetes mellitus (IDDM) and 280 unaffected persons in Korea. HLA typing was performed by the standard microlymphocytotoxicity test using antisera supplied by the Third Asia-Oceania Histocompatibility Workshop Conference (3rd AOHWC, 1986). There was no association between HLA-A, -B, or -C and IDDM. However, the frequencies of HLA-DR3 and HLA-DR4 were increased in the patients as compared with the controls (19.5% vs 4.3%, RR 5.4, corrected p < 0.005 for DR3 and 61.0% vs 36.4%, RR 2.7, corrected p < 0.05 for DR4). Also a decreased frequency of HLA-DR2 was found in the patients with IDDM (9.8% vs 32.1%, RR 0.3, corrected p < 0.05). These results emphasize the differences in HLA-IDDM associations among different ethnic groups.

Ribavirin therapy for Hantaan virus infection in suckling mice

We recently reported that ribavirin inhibited Hantaan virus (HV) replication in vitro. In the present study, we used the HV suckling mouse model to evaluate the efficacy of treatment with various doses of ribavirin. Beginning on day 10, untreated animals, infected with ten times the amount of HV (strain 76/118) required to kill 50% of the animals, lost weight; by days 15 to 18, they developed paralysis of both hind limbs, and they died between days 20 and 21. Treatment with 50 mg of ribavirin/kg per day begun on day 10-following onset of early clinical signs and demonstrable virus in serum and organs--saved 11 of 20 animals compared with 0 of 70 controls. Treated animals did not develop further signs of infection, and by day 22, survivors resumed normal weight gain. After ribavirin treatment, titers of virus decreased in serum, liver, and spleen by two days; in lung within six days; and in the kidney by eight days. By day 18, titers in organs of treated animals were 100-fold lower than in sham-treated animals, with the exception of the brain. Titers of virus in brain fell by day 20, when virus in untreated animals reached greater than 10(7) pfu/g. Treated survivors continued to have decreasing titers of virus in organs and were followed for 75 days with no sign of disease recurrence.

Hantaan virus infection in suckling mice: virologic and pathologic correlates

The Hantaan virus suckling mouse model was examined to delineate virologic and histopathologic characteristics of infection at the organ level. Viral antigen and infectious virus were detected in all organs examined, with highest titers achieved in brain, lung, and kidney. A constellation of histologic lesions was identified in brain (diffuse meningoencephalitis with bilaterally symmetrical thalamic necrosis), liver (pericholangiohepatitis), lung (pneumonitis), and spleen (lymphoid hyperplasia); this tetrad is apparently unique to this model system. The chronology of clinical, virologic, serologic, and pathologic findings in Hantaan-infected newborn mice suggests an immune-mediated mechanism in disease pathogenesis.

Pathogenesis of Hantaan virus infection in suckling mice: clinical, virologic, and serologic observations

Hemorrhagic fever with renal syndrome (HFRS) is a debilitating disease of humans caused by Hantaan virus (HV), the prototype member of a newly proposed genus of Bunyaviridae. Studies of HV pathogenesis have been limited by the absence of a well defined model for a virus-induced disease state. In an attempt to devise a model for HV pathogenesis in laboratory rodents, newborn outbred suckling ICR mice were shown to be uniformly susceptible to lethal infection with non-mouse adapted HV by intracerebral (IC), intraperitoneal (IP), intramuscular (IM), and subcutaneous (SC) inoculation routes. Clinical course, mean time to death, and fatal outcome were age-dependent. With an inoculum of 10 LD50, mortality was 100% in mice infected within 72 hr of birth, but declined to 50% by 7 days. By 2-2.5 weeks, animals developed complete resistance to clinical disease. Virus was consistently detected in serum by day 6 post-infection in IC- and IP-inoculated animals, and reached peak levels of congruent to 10(5) PFU/ml by day 8. Mice infected IM and SC showed delays in onset of viremia, but achieved similar titers. Immunofluorescent antibody appeared by 17-18 days, and neutralizing antibody by 15 days, in all experimental groups. Two of 8 inbred mouse strains were identified as resistant to clinical disease: SJL/J and A/J.