RESUMO
We investigated the geographic diversification of Plestiodon finitimus, which occurs in the central to northern parts of the Japanese Islands, based on a time-calibrated mitochondrial DNA (mtDNA) phylogeny and external morphological characters. The mtDNA phylogeny suggests that P. finitimus diverged from its sister species Plestiodon japonicus in western Japan 2.82-4.63 million years ago (MYA), which can be explained by geographic isolation due to the spread of sedimentary basins in the Pliocene. The primary intraspecific divergence was that between P. finitimus lineages in central and northeastern Japan 1.58-2.76 MYA, which could have been caused by the upliftings of major mountain ranges. In the northeastern lineage, mtDNA and morphological characters suggest a geographic differentiation between sub-lineages of the northwestern Tohoku District (α) and other areas (ß). Although the sub-lineage ß occurs in a disjunct geographic range, consisting of Hokkaido and the central to south of Tohoku, these areas are bridged by populations with intermediate characteristics along the Pacific side of northern Tohoku. Overall, the geographic variation in P. finitimus in northern Japan can be explained by an initial allopatric divergence of the sub-lineages α and ß at 0.71-1.39 MYA, a recent northward expansion of the sub-lineage ß, and subsequent secondary introgressive hybridization between the sub-lineages.
Assuntos
Distribuição Animal , DNA Mitocondrial/genética , Lagartos/fisiologia , Escamas de Animais/anatomia & histologia , Animais , Japão , Lagartos/anatomia & histologia , Lagartos/genética , Filogenia , FilogeografiaRESUMO
A 61-year-old woman, who was revealed to have a 11 mm pulmonary nodule in the right middle lobe by computed tomography, was diagnosed with adenocarcinoma using bronchoscopy. Fluorodeoxyglucose-positron emission tomography (FDG-PET) showed FDG accumulation in the tumor, with a maximum standardized uptake value( SUVmax) of 2.47. Therefore, she underwent thoracoscopic right middle lobectomy. Histopathological examination revealed invasive growth of cylindrical tumor cells with clear glycogen-filled cytoplasm and a relatively high-grade nuclear atypia in tubulopapillary structures; no morula was observed. Immunohistochemically, the membranes of the tumor cells were positively stained for ß-catenin, indicating high-grade fetal adenocarcinoma (pT1bN0M0, pathologic stageâ A2). The postoperative course was uneventful, without recurrence 6 months after surgery.
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Fluordesoxiglucose F18 , Neoplasias Pulmonares , Adenocarcinoma de Pulmão , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Tomografia por Emissão de Pósitrons , Compostos RadiofarmacêuticosRESUMO
A 74-year-old man underwent right upper lobectomy and systemic lymph node dissection with video-assisted thoracoscopic surgery. Chylothorax occurred on postoperative day (POD) 1st. Under fasting management, the patient underwent pleurodesis on POD 5th and 7th, subcutaneous octreotide acetate injection on POD 6th, and lymphangiography on POD 9th. The amount of drainage decreased on POD 10th, and the drainage tube was removed on POD 12nd. Lymphangiography has been reported as one of effective procedures to treat postoperative chylothorax. The present case is also considered to be successfully treated by lymphangiography.
Assuntos
Quilotórax , Linfografia/efeitos adversos , Complicações Pós-Operatórias , Idoso , Quilotórax/etiologia , Humanos , Excisão de Linfonodo , Masculino , Pleurodese , Cirurgia Torácica VídeoassistidaRESUMO
An abnormal lung shadow was detected in a 39-year-old woman at physical examination and she was followed-up carefully at a nearby hospital. After 5 years follow-up, the patient was referred to our hospital for further examination of the abnormal shadow. A chest computed tomography(CT) scan revealed a 12 mm well-circumscribed nodular shadow in the right lower lobe. A benign tumor such as a hamartoma was suspected preoperatively;video-assisted thoracic surgery was performed for both diagnosis and treatment. Partial resection of the right lower lobe was performed and the tumor was diagnosed as an intrapulmonary solitary fibrous tumor (SFT). No malignant features, such as nuclear atypia, necrosis, or mitotic activity, were identified. Careful observation will be necessary, because a few SFTs have a propensity to recur or metastasize. The post-operative course was uneventful and there has been no recurrence at 7 years after surgery.
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Neoplasias Pulmonares/cirurgia , Tumores Fibrosos Solitários/cirurgia , Adulto , Feminino , HumanosRESUMO
A 49-year-old man complaining of fever, chest pain, and hemosputum was examined at a local hospital. A chest computed tomography (CT) scan revealed a 35 mm mass shadow with cavity in the right upper lobe, but a transbronchial lung biopsy could not establish a complete diagnosis. After 1 month follow-up, the patient was referred to our hospital because the mass shadow wall remained thick despite the cavity shrinking. The mass shadow cavity disappeared 2 months after the 1st CT at our hospital. Video-assisted thoracic surgery was performed for both making diagnosis and treatment. The patient was diagnosed with non-small cell lung cancer with pulmonary aspergillosis during surgery, and a right upper lobectomy with systematic lymph node dissection was performed. Pathological examinations revealed that the tumor was a T3N0M0 stage II B adenocarcinoma with pulmonary aspergillosis. The patient was treated with adjuvant chemotherapy 4 months after surgery and is under follow-up.
Assuntos
Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/cirurgia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/cirurgia , Aspergilose Pulmonar/diagnóstico por imagem , Aspergilose Pulmonar/cirurgia , Tomografia Computadorizada por Raios X , Adenocarcinoma/complicações , Adenocarcinoma/patologia , Quimioterapia Adjuvante , Seguimentos , Humanos , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/patologia , Excisão de Linfonodo , Masculino , Pessoa de Meia-Idade , Pneumonectomia/métodos , Aspergilose Pulmonar/complicações , Aspergilose Pulmonar/patologia , Resultado do TratamentoRESUMO
We report a case of solitary pulmonary metastasis from a phyllodes tumor of the breast appearing 16 years after initial surgery. The patient was a 56-year-old woman who had undergone surgical extirpation of a left breast tumor diagnosed as phyllodes tumor (borderline malignancy) in 1998, and a right breast tumor diagnosed as fibromatosis in 2000. Sixteen years after the initial operation, she consulted our hospital because of a chest X-ray abnormality detected at a screening examination. Chest computed tomography revealed a well defined nodular shadow in the left upper lobe of the lung. Surgery was done since primary lung cancer was suspected. However, pathological diagnosis was a pulmonary metastasis from the phyllodes tumor of the left breast. Right breast tumor was also diagnosed as a metastasis from the left breast tumor by histopathological re-evaluation.
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Neoplasias da Mama/patologia , Neoplasias Pulmonares/secundário , Tumor Filoide/secundário , Neoplasias da Mama/cirurgia , Feminino , Humanos , Neoplasias Pulmonares/cirurgia , Pessoa de Meia-Idade , Tumor Filoide/cirurgia , Fatores de Tempo , Tomografia Computadorizada por Raios XRESUMO
Tracheal injury during mediastinoscopic esophagectomy is a life-threatening complication that is challenging to manage. However, no precise treatment has been defined. An 80-year-old male patient with upper esophageal cancer underwent a mediastinoscopic esophagectomy and gastric tube reconstruction through the posterior mediastinal route. When the esophagus was separated from the trachea using a bipolar vessel sealing system, the left side of the membranous trachea incurred a 3-cm defect 7 cm below the sternal notch. We successfully repaired the tracheal injury not by directly suturing the defect but by reinforcing it with a pedicle sternocleidomastoid flap. The gastric tube was placed over the tracheal repair for esophageal reconstruction via a posterior mediastinal route. As a result, the patient recovered well and was discharged. A sternocleidomastoid flap might be another surgical option for reinforcement flaps in tracheal injuries.
Assuntos
Neoplasias Esofágicas , Esofagectomia , Mediastinoscopia , Retalhos Cirúrgicos , Traqueia , Humanos , Masculino , Idoso de 80 Anos ou mais , Neoplasias Esofágicas/cirurgia , Traqueia/cirurgia , Traqueia/lesões , Mediastinoscopia/métodos , Esofagectomia/métodosRESUMO
Pulmonary metastasectomy in colorectal cancer (CRC) has encouraging results; however, specific criteria for lung resection and the timing of resection remain undetermined. Therefore, in this study, we aimed to examine the long-term prognosis and 10-year survival rates and analyze poor prognostic factors in patients who underwent resection of pulmonary metastases from CRC. This retrospective, single-institution study included 156 patients with controlled primary CRC and metastases confined to the lungs or liver who underwent pulmonary metastasectomy between 2005 and 2022. Statistical analyses were conducted using the X2 and two-tailed Student's t test to compare variables. The receiver operating characteristic (ROC) curve was used to determine the appropriate cut-off point for tumor size as a predictive factor of survival. Recurrence-free survival (RFS) and overall survival (OS) were estimated using the Kaplan-Meier method, and non-parametric group comparisons were performed using log-rank tests. The 5- and 10-year OS rates were 67% and 59%, respectively. Further, there was no recurrence 38 months post-surgery, and the RFS curve plateaued. Moreover, by 88 months post-surgery, no deaths occurred, and the OS curve plateaued. Multivariate analysis revealed that a pulmonary metastatic tumor >14 mm and disease-free interval <2 years indicated poor prognosis. The RFS curve for pulmonary metastasectomy may plateau approximately 3 years after surgery. Pulmonary metastasectomy can achieve long-term survival in selected patients with CRC. Furthermore, surgical resection of recurrence after pulmonary metastasectomy may lead to better results. Thus, tumor size and disease-free interval may be independent prognostic factors.
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ABSTRACT: Pulmonary diffuse lymphoid hyperplasia (DLH), a nonneoplastic lymphoproliferative disorder (LPD), is extremely rare, and no PET/CT findings have been reported for pulmonary DLH. We observed slowly expanding irregular opacities with 18 F-FDG accumulation (SUV max , 3.64) in the right lower lobe of a 51-year-old asymptomatic man. The patient underwent video-assisted thoracoscopic biopsy on suspicion of malignant lesions. Histologically, no neoplastic cells were present, and the lesion was consistent with DLH. Six months later, the patient developed rheumatoid arthritis. DLH should be considered in the differentiation of PET-positive irregular opacities, even in the absence of known immune abnormalities.
Assuntos
Artrite Reumatoide , Pneumopatias , Transtornos Linfoproliferativos , Masculino , Humanos , Pessoa de Meia-Idade , Fluordesoxiglucose F18 , Hiperplasia/complicações , Hiperplasia/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Pulmão/diagnóstico por imagem , Artrite Reumatoide/complicações , Artrite Reumatoide/diagnóstico por imagem , Pneumopatias/complicações , Pneumopatias/diagnóstico por imagem , Transtornos Linfoproliferativos/complicações , Transtornos Linfoproliferativos/diagnóstico por imagemRESUMO
To reveal the diversity of Indonesian bent-toed geckos, we pay attention to Kalimantan (Borneo)an island which has received less attention than other Indonesian islands such as Sumatra, Java, Sulawesi, the Moluccas, and the Lesser Sunda archipelagos. About 30 years after Hikida (1990) described three new Cyrtodactylus from Borneo, four more species were described, namely C. limajalur and C. muluensis in 2019, and C. hantu and C. miriensis in 2021, all by Davis et al. Through examination of the collection at MZB and three addition specimens collected from Tawau, we found several undescribed species, one of which we describe here. This new species is easily differentiated from all other congeners by the combination of the following characters: maximum SVL of at least 65.8 mm; no tubercles on dorsal surface of upper arm; tubercles present in the ventrolateral body folds; 2830 paravertebral tubercles; 1720 longitudinal dorsal tubercle rows; 3946 ventral scale rows at midbody; 1719 subdigital lamellae on fourth toe; precloacal pit with 57 pores in males arranged in a wide -shape but absent in females; no enlarged transverse median subcaudals; paired dark brown semilunar-shaped markings on the upper nape. Further study is needed to reveal its molecular phylogenetic position and biogeographical history.
Assuntos
Lagartos , Distribuição Animal , Estruturas Animais , Animais , Bornéu , Feminino , Masculino , FilogeniaRESUMO
PURPOSE: Bronchopleural fistula (BPF) is a potential serious complication of lobectomy or more radical surgery for non-small-cell lung cancer (NSCLC). We aimed to evaluate the risk factors for BPF. METHODS: The study cohort comprised 635 patients who had undergone lobectomy or more radical surgery for NSCLC from March 2005 to December 2017. We examined the following risk factors for BPF: surgical procedure, medical history, preoperative treatment, and surgical management. RESULTS: In all, 10 patients (1.6%) had developed postoperative BPFs. Univariate logistic regression analysis showed that surgical procedure, medical history (arteriosclerosis obliterans [ASO]), and bronchial stump reinforcement were significant risk factors. Multivariate analysis showed that only surgical procedure (right lower lobectomy, p = 0.011, odds ratio = 17.4; right middle lower lobectomy, p = 0.003, odds ratio = 59.4; right pneumonectomy, p <0.001, odds ratio = 166.0) was a significant risk factor. Multivariate analysis confined to the surgical procedure of lobectomy showed that right lower lobectomy (p = 0.011, odds ratio = 36.5) and diabetes (HbA1c ≥8.0) (p = 0.022, odds ratio = 31.7) were significant risk factors. CONCLUSION: When lobectomy or more radical surgery is performed for NSCLC, right lower lobectomy, middle lower lobectomy, and right pneumonectomy are significant risk factors for postoperative BPF. Thoracic surgeons should acquire the techniques of bronchoplasty and angioplasty to avoid such invasive procedures.
Assuntos
Fístula Brônquica/etiologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/cirurgia , Doenças Pleurais/etiologia , Pneumonectomia/efeitos adversos , Fístula do Sistema Respiratório/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Fístula Brônquica/terapia , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Doenças Pleurais/terapia , Fístula do Sistema Respiratório/terapia , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Adulto JovemRESUMO
Objective: We report two cases of acute proximal anterior circulation occlusion after pulmonary lobectomy. Case Presentation: Case 1 was a 64-year-old male who presented with occlusion of the right middle cerebral artery (MCA) one day after left lower lobectomy. Case 2 was a 68-year-old male who presented with occlusion of the right internal carotid artery (ICA). In both cases, mechanical thrombectomy was performed for complete recanalization and symptoms were improved. Conclusion: Prompt mechanical thrombectomy in the acute phase after pulmonary lobectomy improved the prognosis of patients with acute proximal anterior circulation occlusion. It is important to share information about ischemic complications with medical staff engaged in thoracic surgery.
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Performance of thoracoscopic pulmonary segmentectomy for primary lung cancer or pulmonary metastases has recently increased. In patients with emphysema, identification of the intersegmental line is often difficult. For nonpalpable lesions, securing a sufficient surgical margin is more likely to be uncertain. The purpose of this study was to evaluate the efficacy of intraoperative computed tomography (CT) scan during video-assisted thoracoscopic surgery (VATS) pulmonary segmentectomy. This study included 12 patients who underwent intraoperative CT-assisted VATS segmentectomy between January 2015 and August 2016. After dividing the corresponding vessels and bronchi, the intersegmental line was marked by clipping, and intraoperative CT scan was performed under bilateral lung ventilation. The intraoperative CT or 3-dimensional CT reconstruction images were used by the surgeons to confirm the correct anatomical segmental border and to secure a sufficient resection margin. In all patients, the location of the lesions to be resected, the intersegmental border, and the surgical margins could be confirmed while performing VATS segmentectomy. Complete resection was achieved in all patients. Although the pathologic margins tended to be shorter than the surgical margins on intraoperative CT images, there was a strong correlation between these 2 variables (r = 0.963, P < 0.0001). Intraoperative CT scan during VATS segmentectomy was useful for identifying the location of nonpalpable lesions, confirming anatomical intersegmental borders and securing the resection margins. Intraoperative CT navigation could enable a more definitive VATS segmentectomy for nonpalpable lesions.
Assuntos
Cuidados Intraoperatórios/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/cirurgia , Pneumonectomia/métodos , Cirurgia Assistida por Computador/métodos , Cirurgia Torácica Vídeoassistida/métodos , Tomografia Computadorizada por Raios X , Idoso , Idoso de 80 Anos ou mais , Pontos de Referência Anatômicos , Feminino , Humanos , Imageamento Tridimensional , Cuidados Intraoperatórios/efeitos adversos , Neoplasias Pulmonares/patologia , Masculino , Margens de Excisão , Pessoa de Meia-Idade , Pneumonectomia/efeitos adversos , Valor Preditivo dos Testes , Interpretação de Imagem Radiográfica Assistida por Computador , Cirurgia Assistida por Computador/efeitos adversos , Cirurgia Torácica Vídeoassistida/efeitos adversos , Resultado do Tratamento , Carga TumoralRESUMO
BACKGROUND: Locating small, non-palpable lung tumors during video-assisted thoracoscopic surgery (VATS) is difficult. In this paper, we report a simple method to identify such tumors during VATS, using intraoperative computed tomography (IO-CT). METHODS: From 2015 to 2017, we performed IO-CT scans for patients who preoperatively seemed to have non-palpable lung tumors. We initially tried to locate these tumors by finger palpation through the thoracoscopic ports. IO-CT scans were performed after marking tumors with metal clips. However, difficult-to-palpate tumors were marked by initially locating the intercostal muscle from preoperative CT. Metal clips were applied just under the intercostal muscle, and IO-CT scans were performed. After locating the tumor in relationship to the marking clips, patients would undergo wedge resections during VATS, using surgical staplers. RESULTS: We used this procedure on 21 tumors in 18 patients, including 9 non-palpable tumors and 12 palpable tumors (mean tumor size: 7.3 mm; mean distance from pleura: 6.8 mm). All tumors were identified intraoperatively, and all patients successfully underwent wedge resections during VATS, with no intra-postoperative complications. CONCLUSION: IO-CT scans after tumor marking with metal clips during VATS can accurately locate non-palpable small sized lung tumors. IO-CT scans should be indicated for tumors that are preoperatively considered to be non-palpable.
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OBJECTIVE: We investigated whether implantation of polylactic acid and epsilon-caprolactone copolymer (PLAC) cubes with or without basic fibroblast growth factor (b-FGF) released slowly from gelatin microspheres was able to induce fibrous tissue in the dead space remaining after pneumonectomy in the thoracic cavity. METHODS: Left pneumonectomy was performed in Japanese white rabbits. In the control group (n=6), the left thoracic cavity was closed without any treatment. In the FGF group (n=6), gelatin microspheres that released 100 microg of b-FGF were implanted into the left thoracic cavity. In the PLAC group (n=6), PLAC cubes were implanted into the left thoracic cavity. In the PLAC/FGF group (n=6), both PLAC cubes and gelatin microspheres releasing 100 microg of b-FGF were implanted into the left thoracic cavity. RESULTS: In the control and FGF groups, herniation of the heart, mediastinal shift, and overinflation of the right lung were observed. No granular tissue formation was observed. In the PLAC and PLAC/FGF groups, a dense area of newly formed soft tissue was observed, and only a mild mediastinal shift was observed during the 3-month follow-up period. Pathological examination revealed induction of fibrous and granular tissue in the left thoracic cavity. The foreign-body reaction induced by PLAC was very mild. CONCLUSIONS: Implantation of PLAC cubes with or without gelatin microspheres releasing 100 microg of b-FGF is able to induce fibrous tissue in the post-pneumonectomy dead space.
Assuntos
Caproatos/administração & dosagem , Fatores de Crescimento de Fibroblastos/administração & dosagem , Lactonas/administração & dosagem , Pneumonectomia/efeitos adversos , Complicações Pós-Operatórias/prevenção & controle , Engenharia Tecidual/métodos , Animais , Caproatos/farmacologia , Células do Tecido Conjuntivo/efeitos dos fármacos , Células do Tecido Conjuntivo/fisiologia , Preparações de Ação Retardada/administração & dosagem , Fatores de Crescimento de Fibroblastos/farmacologia , Tecido de Granulação/efeitos dos fármacos , Tecido de Granulação/crescimento & desenvolvimento , Implantes Experimentais/normas , Ácido Láctico/administração & dosagem , Ácido Láctico/farmacologia , Lactonas/farmacologia , Poliésteres , Polímeros/administração & dosagem , Polímeros/farmacologia , Coelhos , Cavidade TorácicaRESUMO
OBJECTIVE: The optimal surgical treatment for non-small cell lung cancer (NSCLC) with vertebral body invasion remains both controversial and challenging. We reviewed our experiences of NSCLC with vertebral body invasion, in which we have performed induction chemoradiotherapy followed by lung resection with en bloc partial vertebrectomy. METHODS: Six NSCLC patients with vertebral invasion underwent an operation following chemoradiotherapy from January 2001 to July 2006. Vertebral invasion was evaluated by the chest CT and MRI findings. Either carboplatin-paclitaxel (n=3) or carboplatin-docetaxel (n=3) was used. Two cycles of chemotherapy were performed with concurrent radiation (50 Gy) treatment. RESULTS: In all of the six cases, a complete resection with en bloc partial vertebrectomy was performed with no operative mortality. The histological complete response rate and major response rate were 16.7% (1/6) and 83.3% (5/6), respectively. The 5-year overall survival rate was 67.7%. In addition, no local failure was observed after surgery. CONCLUSIONS: Surgery after chemoradiotherapy (carboplatin/paclitaxel or docetaxel and 50 Gy radiation) for NSCLC with vertebral invasion could thus be performed with acceptable morbidity.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/terapia , Neoplasias da Coluna Vertebral/cirurgia , Coluna Vertebral/cirurgia , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adenocarcinoma/terapia , Idoso , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Carcinoma de Células Escamosas/terapia , Terapia Combinada/métodos , Feminino , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Análise de Sobrevida , Procedimentos Cirúrgicos Torácicos/métodos , Resultado do TratamentoRESUMO
The Chinese skink, Plestiodon chinensis (Gray, 1838), is widely distributed across continental China, Taiwan, the Korean Peninsula, and offshore islets, and consists of several subspecies. Here morphological and molecular methods have been used to reassess the taxonomic status and distributions of P. c. formosensis (Van Denburgh, 1912) and P. c. leucostictus (Hikida, 1988), which are endemic to Taiwan and Green Island (an islet off the east coast of Taiwan), respectively. It can be confirmed that the eastern Taiwanese populations of P. c. formosensis exhibit similar juvenile color patterning and genetic composition to the islet subspecies P. c. leucostictus, and are distinct from consubspecific populations in western Taiwan. Therefore, the eastern Taiwanese populations are assigned to P. c. leucostictus, and this subspecies is recognized as a distinct species, Plestiodon leucostictus (Hikida, 1988), based on their unique juvenile coloration and highly divergent DNA sequences. Our results also revealed that P. c. formosensis in western Taiwan is close to nominotypical subspecies from the continent, suggesting the necessity of a comprehensive taxonomic analysis in the future.
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The scincid lizard Plestiodon latiscutatus is found in the Izu Islands and Izu Peninsula of central Japan, whereas P. japonicus, a close relative, is found over the entire main island group of Japan, except the Izu Peninsula. The precise area of occupancy of these species was surveyed around the Izu Peninsula. Species identification was made through comparison of mitochondrial DNA partial sequences of specimens from the Izu Peninsula with those from the other regions, since morphological differences between these species have not yet been characterized. This study determined that these species are deeply diverged from each other in mitochondrial DNA sequence, and that the ranges of these species overlap only in a narrow zone. The results imply that gene flow between these species, if any, is restricted to a low level, without physical barriers. The boundary between the geographic ranges of these species was established as occurring along the lower Fuji River, Mt. Fuji, and the Sakawa River. This region is concordant with that of the old sea that is assumed to have separated the Izu Peninsula from other parts of the Japanese main island group until the middle Pleistocene. This pattern suggests that P. latiscutatus and P. japonicus were differentiated allopatrically before the connection of land areas of the Izu Peninsula and Honshu, the main island of Japan, and come into secondary contact through this connection. Thus, the species boundary is likely to have been maintained in situ, without physical barriers, since the secondary contact in the middle Pleistocene.
Assuntos
DNA Mitocondrial/química , Ecossistema , Variação Genética , Lagartos/classificação , Lagartos/genética , Animais , Sequência Consenso , DNA Ribossômico/química , Evolução Molecular , Genética Populacional , Geografia , Haplótipos , Japão , Funções Verossimilhança , Filogenia , RNA Ribossômico 16S/genética , Alinhamento de Sequência/veterinária , Especificidade da Espécie , Fatores de TempoRESUMO
We investigated the efficiency of basic fibroblast growth factor (b-FGF) released from a gelatin sponge in the regeneration of tracheal cartilage. A 1-cm gap was made in the midventral portion of each of 10 consecutive cervical tracheal cartilages (rings 4 to 13) in 15 experimental dogs. In the control group (n = 5), the resulting gap was left blank. In the gelatin group (n = 5), a gelatin sponge alone was implanted in the gap. In the b-FGF group (n = 5), a gelatin sponge containing 100 mug b-FGF solution was implanted in the gap. We euthanatized one of the five dogs in each group at 1 month after implantation and one at 3 months and examined the implant sites macroscopically and microscopically. In the control and gelatin groups, no regenerated cartilage was observed in the tracheal cartilage gap at 1 or 3 months. The distances between the cartilage stumps had shrunk. In the b-FGF group, fibrous cartilage had started to regenerate from both host cartilage stumps at 1 month. At 3 months, regenerated fibrous cartilage filled the gap and had connected each of the stumps. The regenerated cartilage was covered with regenerated perichondrium originating from the host perichondrium. Shrinkage of the distance between the host cartilage stumps was not observed in the b-FGF group. We succeeded in inducing cartilage regeneration in the gaps in canine tracheal cartilage rings by using the slow release of b-FGF from a gelatin sponge. The regenerated cartilage induced by b-FGF was fibrous cartilage.