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1.
Biomedicines ; 12(5)2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38790898

RESUMEN

Growing research has proposed that rheumatoid arthritis (RA) and chronic periodontitis (CP) share similar pathophysiological mechanisms involving inflammation and tissue destruction. However, the potential correlation of CP as a contributing factor for the occurrence of RA warrants validation in the Korean population, where both diseases are prevalent, especially considering the increasingly aging demographic in Korea. This study examined 5139 RA cases and 509,727 matched controls from a Korean national cohort dataset (2002-2019) by carefully employing propensity score matching to ensure comparability between groups. Baseline characteristics were compared using standardized differences, and logistic regression was employed to estimate the impact of CP history on RA likelihood while controlling for covariates. We fully examined medical records documenting CP occurrences within the two-year period leading up to the index date, conducting comprehensive subgroup analyses. While a 1-year history of CP did not show a significant association with likelihood of RA, a 2-year history of CP increased RA likelihood by 12%, particularly among older adults, females, rural residents, and those with certain comorbidities such as hypercholesterolemia. Interestingly, this association persisted even among individuals with non-smoking habits, normal weight, and infrequent alcohol consumption. These findings suggest that chronic CP exposure for at least 2 years may independently elevate RA risk in Korean adults. The association in certain subgroups appears to suggest a predisposition toward genetic susceptibilities over lifestyle and environmental factors. Predicting RA in CP patients may be challenging, emphasizing the importance of regular RA screening, especially in high-risk subgroups.

2.
Biomedicines ; 12(4)2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38672147

RESUMEN

Recent research suggests a potential relevance between chronic periodontitis (CP) and Parkinson's disease (PD), raising concerns about comorbid PD among elderly CP patients. However, the epidemiologic basis for this association remains unclear. Employing a nested case-control design, this study explored the association between CP and subsequent PD occurrences in Korean adults, leveraging a validated national population-based dataset covering the period from 2002 to 2019. It included 8794 PD patients and 35,176 matched control individuals, established through propensity score matching for age, sex, residential area, and income. Baseline characteristics were compared using standardized differences, and logistic regression was employed to assess the impact of CP histories on PD likelihood while controlling for covariates. We performed a thorough examination of CP events within both 1-year and 2-year intervals preceding the index date, incorporating subgroup analyses. Our analysis revealed no statistically significant association between CP history and PD development overall. However, subgroup analysis revealed a slightly increased likelihood of PD development among CP individuals with a high disease burden (Charlson Comorbidity Index score ≥ 2). In conclusion, although our study did not find a significant overall association between CP history and PD development, the elevated likelihood of PD in subgroups with high disease burden may suggest that comorbidities influence PD probability among certain CP patients. Considering comorbid conditions in PD screening for some individuals with CP may be also important.

3.
J Pers Med ; 14(4)2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38672983

RESUMEN

While headaches frequently occur in individuals with chronic kidney disease (CKD), there are few statistical evaluations of their connection to migraines in population-based studies. In this nationwide longitudinal follow-up study of Korean health examination data (2002-2019), a total of 15,443 participants with CKD and 61,772 matched controls were enrolled. We applied overlap-weighted Cox proportional hazard regression models to assess hazard ratios, examining the correlation between CKD and the development of migraines. After accounting for various factors, we observed a modest reduction of approximately 11% in the likelihood of migraine occurrence among CKD patients (95% confidence intervals = 0.81-0.97) during the 16-year monitoring period. Subgroup analysis revealed a significant association among specific demographic and health conditions, including individuals aged 70 or older, females, overweight individuals, nonsmokers, and those without hypertension or diabetes. Our research may indicate a potential relationship between CKD and the onset of migraines in Korean adults, suggesting a slight reduction in the probability of the occurrence of migraines among those with CKD. These findings emphasize the need for attentive follow-up and preventive management in individuals without the identified protective factors, particularly in male CKD patients under the age of 70 with hypertension.

4.
J Pers Med ; 14(3)2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38540972

RESUMEN

Given the global significance of gout and gastric cancer (GC) as major health problems with interrelated impacts, we examined the development of GC in Korean patients with gout. We conducted a nested case-control study using data from 10,174 GC patients and 40,696 control patients from the Korean National Health Insurance Service-National Sample Cohort database. Propensity score matching (1:4) with propensity score overlap-weighted adjustment was used to reduce selection bias and estimate the odds ratio (OR) and 95% confidence intervals (CIs) for the association between gout and GC. An adjusted OR for GC was not significantly higher in patients with gout than in control patients (1.02; 95% CI, 0.93-1.12; p = 0.652). Additionally, no association between gout and GC was observed in subgroup analyses such as sex, age, level of income, region of residence, or Charlson Comorbidity Index score. In conclusion, these results suggest that gout is not a significant independent risk factor for GC among the Korean population. Additional investigation is required to establish a causal association between gout and GC, and to generalize these results to general populations.

5.
PLoS One ; 19(2): e0292916, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38422090

RESUMEN

Climate changes have altered biodiversity and ultimately induced community changes that have threatened the survival of certain aquatic organisms such as fish species. Obtaining biological and genetic information on endangered fish species is critical for ecological population management. Thamnaconus multilineatus, registered as an endangered species by the IUCN in 2019, is a Data Deficient (DD) species with a remarkably small number of habitats worldwide and no known information other than its habitat and external form. In this study, we characterized the external and osteological morphology of a T. multilineatus specimen collected from eastern Jeju Island, South Korea, in 2020. We also investigated the phylogenetic relationships among related fish species through complete mitochondrial DNA (mtDNA) analysis of the T. multilineatus specimen. The external and skeletal characteristics of T. multilineatus were similar to those of previous reports describing other fish of the genus Thamnaconus, making it difficult to classify T. multilineatus as a similar species based only on morphological characteristics. As a result of analyzing the complete mtDNA of T. multilineatus, the length of the mtDNA was determined to be 16,435 bp, and the mitochondrial genome was found to have 37 CDCs, including 13 PCGs, 22 tRNAs, and 2 rRNAs. In the phylogenetic analysis within the suborder Balistoidei, T. multilineatus mtDNA formed a cluster with fish of the genus Thamnaconus. This study is the first to report on the skeletal structure and complete mtDNA of T. multilineatus. Since the current research on T. multilineatus has only been reported on morphology, the results of this study will be utilized as important information for the management and restoration of T. multilineatus as an endangered species and significant fishery resource.


Asunto(s)
Tetraodontiformes , Animales , Filogenia , ADN Mitocondrial/genética , Mitocondrias , Biodiversidad , Especies en Peligro de Extinción
6.
Cancers (Basel) ; 15(23)2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38067309

RESUMEN

Considering the global importance of both gout and colorectal cancer (CRC) as significant health issues with mutual relevance, we aimed to examine the risk of colorectal cancer in Korean patients with gout. In this nested case-control study, we used data from 9920 CRC patients and 39,680 controls the Korean National Health Insurance Service-National Sample Cohort database. Propensity score overlap-weighted multivariate logistic regression analyses, adjusted for confounders, were used to assess the odds ratio (OR) and 95% confidence interval (CI) of the association between gout and CRC. Adjusted OR for CRC were similar between patients with gout and the control group (0.95; 95% CI, 0.86-1.04; p = 0.282). However, after adjustment, subgroup analysis revealed an 18% reduction in the probability of CRC among patients younger than 65 years with gout (95% CI, 0.70-0.95; p = 0.009). Conversely, absence of an association between gout and subsequent CRC persisted regardless of sex, income, residence, and Charlson Comorbidity Index score, even among individuals aged 65 years or older. These results imply that gout may not be a significant independent risk factor for CRC among the general population. However, in patients younger than 65 years with gout, a slightly reduced likelihood of CRC was observed. Further research is necessary to establish a causal relationship between gout and CRC and to generalize these findings to other populations.

7.
Cancers (Basel) ; 15(23)2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38067310

RESUMEN

The potential connection between proton pump inhibitors (PPIs) and colorectal cancer (CRC) risk remains unclear, with specific ethnic genetic backgrounds playing a role in PPI-induced adverse effects. In this nested case-control study, we investigated the risk of CRC in relation to preceding PPI use and the duration of use using data from the Korean National Health Insurance Service-National Sample Cohort database, including 9374 incident CRC patients and 37,496 controls. To assess the impact of preceding PPI exposure (past vs. current) and use duration (days: <30, 30-90, and ≥90) on incident CRC, we conducted propensity score overlap-weighted multivariate logistic regression analyses, adjusted for confounding factors. Our findings revealed that past and current PPI users had an increased likelihood of developing CRC. Regardless of duration, individuals who used PPIs also had higher odds of developing CRC. Subgroup analyses revealed that CRC occurrence increased independent of history or duration of prior PPI use, consistent across various factors such as age, sex, income level, and residential area. These findings suggest that PPI use, regardless of past or present use and duration of use, may be related to an increased risk of developing CRC in the Korean population.

8.
Front Endocrinol (Lausanne) ; 14: 1195888, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37680887

RESUMEN

Objective: Accumulating evidence from other countries indicates potential associations between gout and cardiovascular diseases; however, the associations of gout with cardiovascular diseases, particularly stroke, ischemic heart disease, and heart failure, remain ambiguous in the Korean population. We hypothesized that individuals with gout are at a higher likelihood of stroke, ischemic heart disease, or heart failure. This study expands upon previous research by ensuring a comparable baseline between patient and control groups and analyzing 16 years of data derived from an extensive healthcare database. Methods: We selected 22,480 patients with gout and 22,480 control individuals from the Korean National Health Insurance Service-Health Screening Cohort database (2002-2019), and matched them at a 1:1 ratio according to sex, age, income, and residence. A Cox proportional hazard model with weighted overlap was employed to examine the relationship between gout and the risk of stroke, ischemic heart disease, or heart failure after adjustment for several covariates. Results: The incidences of stroke, ischemic heart disease, or heart failure in participants with gout were slightly higher than those in controls (stroke: 9.84 vs. 8.41 per 1000 person-years; ischemic heart disease: 9.77 vs. 7.15 per 1000 person-years; heart failure: 2.47 vs. 1.46 per 1000 person-years). After adjustment, the gout group had an 11% (95% confidence interval [CI] = 1.04-1.19), 28% (95% CI = 1.19-1.37), or 64% (95% CI = 1.41-1.91) higher likelihood of experiencing stroke, ischemic heart disease, or heart failure, respectively, than the control group. Conclusion: The present findings suggest that individuals with gout in the Korean population, particularly those aged ≥ 60 years, were more likely to have stroke, ischemic heart disease, or heart failure.


Asunto(s)
Enfermedades Cardiovasculares , Gota , Insuficiencia Cardíaca , Isquemia Miocárdica , Accidente Cerebrovascular , Humanos , Estudios de Seguimiento , Insuficiencia Cardíaca/epidemiología , Insuficiencia Cardíaca/etiología , Isquemia Miocárdica/complicaciones , Isquemia Miocárdica/epidemiología , Gota/complicaciones , Gota/epidemiología , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , República de Corea/epidemiología
9.
BMC Musculoskelet Disord ; 24(1): 486, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37312057

RESUMEN

PURPOSE: The relationship between retear that may occur after rotator cuff repair and patient satisfaction is not well established. This study aimed to determine whether the types and size of the retear evaluated by computed tomography arthrography (CTA) influenced patient satisfaction. We also analyzed the patient factors that could affect patient satisfaction. PATIENTS AND METHODS: A total of 50 patients who were diagnosed with rotator cuff retear after undergoing arthroscopic rotator cuff repair were included in this study. All the patients were dichotomously classified into the satisfactory or dissatisfactory groups according to the patients' self-classifications. CTA was used to assess the attachment status of the footprint, detect retear on the medial side of the footprint of the repaired cuff, and determine the retear size. Demographic factors, including sex, age, occupation, dominant upper extremity, duration of pain, presence of diabetes mellitus, trauma history, history of ipsilateral shoulder surgery, repair technique, worker's compensation status, and functional shoulder score, were investigated. RESULTS: Thirty-nine patients were classified into the satisfactory group and 11 patients were classified into the dissatisfactory group. There were no differences in age, sex, occupation, dominant hand, duration of pain, presence of diabetes mellitus, trauma history, history of ipsilateral shoulder surgery, repair technique, worker's compensation, and duration of follow-up between the two groups. However, the postoperative American Shoulder and Elbow Surgeon (ASES) score (P < 0.01), visual analog scale (VAS) pain level (P < 0.01), anteroposterior (AP) length (P < 0.01), and area of the retear site (P < 0.01) were significantly different. CONCLUSION: The AP length and area of the retear site estimated using CTA were confirmed as the significant risk factors for dissatisfaction. However, the type of repaired rotator cuff judged by the attachment status of the footprint did not correlate with patient satisfaction. In addition, the postoperative VAS pain scale and ASES score was correlated with patient satisfaction.


Asunto(s)
Satisfacción del Paciente , Manguito de los Rotadores , Humanos , Manguito de los Rotadores/diagnóstico por imagen , Manguito de los Rotadores/cirugía , Artrografía , Dolor , Satisfacción Personal
10.
Acta Orthop Traumatol Turc ; 57(1): 30-35, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36939362

RESUMEN

OBJECTIVE: The aim of this study was to compare radiological and clinical results between early (≤3 weeks) and late (>3 weeks) removal of pins in patients treated with the stepwise percutaneous leverage technique for radial neck fractures. METHODS: 37 patients (aged 3-15) who underwent fixation with stepwise percutaneous leverage technique for Judet class III and class IV radial neck fractures between 2003 and 2019 were included in this retrospective study. Patients were divided into two groups according to the time of pin removal; 19 had early pin removal (≤3 weeks) and 18 had late pin removal (>3 weeks). The patients' radiological results were graded using the Metaizeau classification and their clinical results were evaluated by measuring their range of motion (ROM) and Mayo elbow performance scores (MEPS) at postoperative follow-ups. Statistical tests, including the Mann-Whitney U and Chi-square tests, were performed to compare the demographic factors and outcomes. RESULTS: The mean time of removal of pins for all patients was 21 (10-43) days. The mean time for early and late removal was 15.1 (10-21) and 27.6 (22-43) days, respectively. There was no statistically significant difference between groups radiologically according to the Metaizeau classification (P = .723). Furthermore, no statistically significant difference was found in the ROM (extension/flexion: P = .620, pronation/supination: P = .578) or MEPS (P = .695) between groups. CONCLUSION: This study has shown us that early removal of pins in patients with pediatric radial neck fractures treated with stepwise percutaneous leverage technique demonstrated good radiological and clinical results comparable to late pin removal. Level of Evidince: Level IV, Therapeutic Study.


Asunto(s)
Fijación Intramedular de Fracturas , Fracturas Radiales de Cabeza y Cuello , Fracturas del Radio , Humanos , Niño , Estudios Retrospectivos , Fijación Intramedular de Fracturas/métodos , Resultado del Tratamiento , Clavos Ortopédicos , Fracturas del Radio/diagnóstico por imagen , Fracturas del Radio/cirugía , Fijación Interna de Fracturas/métodos , Rango del Movimiento Articular
11.
J Hand Surg Eur Vol ; 48(7): 625-629, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36708152

RESUMEN

We systematically reviewed the incidence of complications and outcomes of different surgical methods for acute perilunate injury in the MEDLINE, Scopus, Embase and Cochrane Library databases. Forty-three articles with 880 patients were included. The most common complications were arthritis (30%), carpal instability (15%), avascular necrosis of the lunate (12%), complex regional pain syndrome (11%), and nonunion or avascular necrosis of the scaphoid (9%). In the meta-analysis, the mean scapholunate gap was 1.7 mm in the closed surgery group and 2.3 mm in the open surgery group, which was a statistically significant difference. The mean flexion-extension arc of the wrist and modified Mayo wrist score were better in the closed surgery group than in the open surgery group. However, these findings may relate to different cohorts in terms of injury severity. Therefore, the causal relationship between closed surgery and better outcomes may be uncertain as less severe subluxations are more likely to be treated closed.


Asunto(s)
Fracturas Óseas , Luxaciones Articulares , Inestabilidad de la Articulación , Hueso Semilunar , Hueso Escafoides , Traumatismos de la Muñeca , Humanos , Fracturas Óseas/cirugía , Inestabilidad de la Articulación/cirugía , Luxaciones Articulares/cirugía , Hueso Semilunar/cirugía , Hueso Semilunar/lesiones , Hueso Escafoides/cirugía , Hueso Escafoides/lesiones , Necrosis , Traumatismos de la Muñeca/cirugía
12.
Plants (Basel) ; 11(15)2022 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-35956513

RESUMEN

This study was conducted to evaluate the effects of different artificial light sources on the growth characteristics and various biological activities of the Atractylodes macrocephala x Atractylodes japonica hybrid cv. 'Dachul', which is highly useful for medicinal purposes. The plant had the largest biomass with a plant height of 38.20 ± 1.95 cm when treated with microwave electrodeless light (MEL). The chlorophyll content of the plants treated with fluorescent light (FL) was 53.93 ± 1.05 SPAD and was the highest. The antioxidant effect, determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), was the highest with 92.7 ± 0.2% in plants treated with light-emitting diode (LED)-green light. Total phenol and flavonoid contents were significantly higher with 19.7 ± 0.5 mg GAE/g and 40.2 ± 2.2 mg QE/g in the sample treated with LED-green light, respectively. For antimicrobial activity using the minimum inhibitory concentration (MIC) technique, the inhibitory ability against Escherichia coli was at 0.25 mg/mL under LED-green light treatment. The whitening activity using tyrosinase enzyme showed the highest tyrosinase inhibitory ability at 62.1 ± 1.2% of the above extract treated with MEL light. To confirm the immune activity in lipopolysaccharide (LPS)-induced RAW 264.7 cells, NO production of inflammation-related substances was measured. In addition, the inflammation-related genes iNOS (inducible nitric oxide synthase), COX-2 (cyclooxygenase-2), and TNF-α (tumor necrosis factor-α) in the same sample were confirmed using reverse transcriptase (RT)-PCR, and the result showed that gene expression was suppressed compared with that in the control group. It is expected that Dachul plants treated with LED-blue light will play an important role in enhancing intracellular anti-inflammatory activity. From these results, the effect for various biological activities appeared in a significantly diverse spectrum in response to different wavelengths of artificial light sources in Dachul.

13.
Dev Reprod ; 25(1): 33-41, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33977173

RESUMEN

This study was carried out to observe the development of the autonomous skeletal development of the Favonigobius gymnauchen. Total length (TL) of larvae 3 days after hatching (DAH) were mean TL of 3.34 mm, with a line-shaped parasphenoid ossification in the cranium and basioccipital ossification in the back. The 10 DAH larvae had a mean TL of 5.20 mm, with the number of caudal vertebrae increasing to 15. The urostyle and two hypural bones in the lower part also began to ossify. The 23 DAH juveniles had a mean TL of 8.47 mm. The pectoral girdle's skeleton was completed as the scapula and coracoid were ossified. The pelvic girdle also fully supported the ventral fin as its ossification was completed. Favonigobius gymnauchen and Tridentiger obscurus showed similar characteristics in terms of the anus location of hatched larvae, number of myotomes, and melanophore distribution during the morphological development of the larvae and juveniles. However, this study confirmed differences in the development of the vertebrae and urostyle bone.

14.
Dev Reprod ; 24(2): 125-133, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32734129

RESUMEN

This study is intended to be used as the basic material for the taxonomic research by observing the stages of skeletal development of Luciogobius grandis larvae compared to the skeletal development patterns of the same fish family of Gobiidae. 3 days after hatching (DAH), the preflexion larvae was 4.01±0.11 mm (n=5) in average total length (TL) and the frontal began to ossify in the skull. 17 DAH, the advanced postflexion larvae was 5.37±0.05 mm (n=5) in average TL the supraoccipital and epiotic were ossified in the cranial bone. 36 DAH, the juvenile was 12.2±0.20 mm (n=5) in average TL and the urohyal was ossified in the hyoid arch. In addition to one hypural bone being ossified, the first, second, third and fourth were combined and were made three bone fragments and then, the bone ossification of all skeletons was completed.

15.
Dev Reprod ; 24(1): 63-70, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32411919

RESUMEN

This study aimed to investigate early life of Coreoperca herzi living in Han River and compare morphological differences between different groups during the development in order to provide basic data for relevant taxonomic research. On average, one female individual spawned 541 to 861 eggs (average 701) at once. After 259 hours, the tail broke out of the egg membrane and hatching began. Immediately after hatching, the larvae were average 7.81±0.10 mm (n=5) in total length. 60 days the juvenile was average 35.9±1.30 mm (n=5) in total length. The white spots spread to the rest of the body, rending the same pattern as that on the body of their broodstock fish.

16.
Dev Reprod ; 24(4): 307-316, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33537517

RESUMEN

The purpose of this study is to observe the early life history of Korean Lefua costata and use the result as basic taxonomic research data for balitorid fish. The fertilized eggs were light green color with completely circle shape and mean size was 1.21±0.06 mm (n=30). Immediately after hatching, the size of the larvae was 2.81±0.11 mm (n=5) in mean length, with egg yolk. On the 3rd day after hatching, the preflexion larvae had a mean length of 4.64±0.09 mm (n=5), and their mouth was opened to start feeding. On the 8th day after hatching, a mean length of the postflexion larvae was 9.43±0.46 mm (n=5), the distal part of the notochord was bent to 45°, and 16 fin rays were developed on the caudal fin. On the 31st day after hatching, a mean length of juveniles was 22.3±0.85 mm (n=5), and the number of fin rays was the same as that of adult fish with (iv8) dorsal fins and (iii8) anal fins.

17.
Dev Reprod ; 23(2): 161-170, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31321356

RESUMEN

The purpose of this study is to investigate the development of Coreoleuciscus splendidus egg and larvae morphology in the Ungcheon-stream. C. splendidus eggs were round and ranged in size from 1.86-2.01 mm (mean 1.91±0.14 mm). Immediately after hatching, the larvae had egg yolk in the abdomen with a total length of 5.27-6.63 mm (mean 5.95±0.96 mm). On the 10 days after hatching, the latter was 8.44-8.65 mm (mean 8.54±0.14 mm) in total length, and 5 dorsal fin rays were formed in dorsal fin and 8 caudal fin soft rays were formed in caudal fin. At 88 days after hatching, total length was 26.2-25.7 mm (mean 25.9±0.35 mm), and scales were formed throughout the body. The fin rays of each part were iii.7 in dorsal fin and iii.6 in anal fin, and finally the external form was the same as the adult fish.

18.
Dev Reprod ; 22(3): 205-212, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30324157

RESUMEN

This study is to observe the developmental process of the larval skeleton according to the growth of the trident goby, Tridentiger obscurus belonging to the larvae and juveniles and use it as the basic data of the taxonomic study. 8 days after hatching, the parasphenoid was ossified with an average total length of 3.62 mm, and basioccipital began to ossify. Caudal vertebrae and neural spine ossified in vertebra. 17 days after hatching, the average total length of the long hairs was 4.32 mm, pterotic and epiotic were ossified, and interhyal and subopercle were ossified. 52 days after hatching, the average total length of the juvenile was 18.2 mm, and lateral ethmoid, hypohyal ossified, vertebrae were parapophysis, and epural bone was osseous to the bone.

19.
Dev Reprod ; 22(1): 9-18, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29707680

RESUMEN

This study was conducted to investigate the skeletal development of bullhead torrent catfish, Liobagrus obesus larvae and to utilize them as basic data for the taxonomic study of Liobagrus larvae. Skeletal development was observed by being divided into cranium, visceral skeleton, shoulder girdle bone, pelvic girdle bone and vertebra. On the first day after hatching, the pre-larvae had an average total length of 7.92 mm, and a line-shaped parasphenoid ossified in the cranium. In the jaw bone, the dentary supporting the lower jaw and the maxillary supporting the upper jaw were ossified. In the anterior abdominal vertebrae of the vertebra, seven centrums began to ossify and five neural spines ossified simultaneously. On the 3 day after hatching, pre-larvae had an average total length of 8.95 mm, and the prefrontal ossified in cranium. The number of abdominal vertebrae was increased to 14, and three parapophysis developed from the front side. On the 24th day after hatching, post-larvae had an average total length of 15.2 mm and the epural bone ossified in coccyx. The parhypural bone was ossified, and ossification of coccyx and pelvic girdle bone was completed. On the 30th day after hatching, the average total length of the juvenile was 17.8 mm, and the ossification of cranium and visceral skeleton was all completed while the preorbital and three suborbitals were ossified in the orbital region of the cranium.

20.
Dev Reprod ; 22(1): 39-53, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29707683

RESUMEN

The purpose of this study is to investigate the early life history of the Rhodeus fish, Rhodeus uyekii and R. ocellatus, in the Nakdong River to use as the preliminary data for the systematic study. The embryos used in the study were fertilized eggs (embryo) and larvae after artificial fertilization. The long diameter of the eggs of the R. uyekii was 3.39-3.97 mm (average 3.68±0.41 mm, n=30) and the short diameter was 1.36-1.55 mm (average 1.45±0.13 mm, n=30). The long diameter of the eggs of the R. ocellatus was 2.53-2.71 mm (average 2.62±0.12 mm, n=30) and the short diameter was 1.47-1.60 mm (average 1.53±0.09 mm, n=30). Hatching time was 48 hours for the R. uyekii and 50 hours for the R. ocellatus given that the average water temperature was 21.5°C. The hatched larvae were 4.95-5.00 mm (average 4.98±0.04 mm, n=5) for the R. uyekii and the total length was 3.66-3.69 mm (average 3.67±0.02 mm, n=5) for the R. ocellatus. R. uyekii was found to be 15.5-15.8 mm at total length (average 15.6±0.21 mm, n=5) on the 56 days after hatching with the number of dorsal fins being iii-9, anal fins iii-10, ventral fins iii-5. The R. ocellatus was found to be 15.8-16.0 mm (average 15.9±0.14 mm, n=5) at total length on the 58 days with the number of dorsal fins being iii-11, anal fins iii-12 and ventral fins iii-5 where the number of all fin stalks reached maximum.

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