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1.
Proc Biol Sci ; 288(1964): 20211913, 2021 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-34847767

RESUMO

The extinct Haast's eagle or harpagornis (Hieraaetus moorei) is the largest known eagle. Historically, it was first considered a predator, then a scavenger, but most recent authors have favoured an active hunting ecology. However, the veracity of proposed similarities to carrion feeders has not been thoroughly tested. To infer feeding capability and behaviour in harpagornis, we used geometric morphometric and finite-element analyses to assess the shape and biomechanical strength of its neurocranium, beak and talons in comparison to five extant scavenging and predatory birds. The neurocranium of harpagornis is vulture-like in shape whereas its beak is eagle-like. The mechanical performance of harpagornis is closer to extant eagles under biting loads but is closest to the Andean condor (Vultur gryphus) under extrinsic loads simulating prey capture and killing. The talons, however, are eagle-like and even for a bird of its size, able to withstand extremely high loads. Results are consistent with the proposition that, unlike living eagles, harpagornis habitually killed prey larger than itself, then applied feeding methods typical of vultures to feed on the large carcasses. Decoupling of the relationship between neurocranium and beak shape may have been linked to rapid evolution.


Assuntos
Águias , Falconiformes , Aves Predatórias , Animais , Bico , Nova Zelândia , Comportamento Predatório
2.
Heredity (Edinb) ; 119(5): 360-370, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28792491

RESUMO

The high biodiversity and strong population structure of freshwater fauna has often been attributed to historical geological and climatic alterations. The impact of these historical changes on obligate freshwater species on a small geographical scale has not been well understood due to the lack of fine-scale comparative phylogeographic studies. Strong population structure has been reported in a goby and a caridean shrimp in Hong Kong, a small but highly developed city in South China, but the common drivers of population differentiation in freshwater fauna in this region remain unclear. This study examined the fine-scale phylogeographic patterns of two freshwater loaches, Schistura fasciolata and Pseudogastromyzon myersi in Hong Kong, using sequence data of mitochondrial control region and two nuclear markers (interphotoreceptor retinoid binding protein gene 2 and ribosomal protein S13 gene). Results show that they exhibit pronounced population structure as supported by high and significant ΦST. Phylogenetic analyses based on the control region reveal six and three distinct lineages in S. fasciolata and P. myersi, respectively. Phylogeographic structure of both species generally follows the paleodrainage pattern, though P. myersi shows a shallower structure on the Mainland, perhaps due to their higher mobility. Most of these lineages diverged during the Pliocene and Late Pleistocene, a period with marked sea-level fluctuations. In a broader context, this suggests that sea-level fluctuation played an important role in shaping even the fine-scale population structure of freshwater fish in South China, implying that the genetic diversity of this fauna may be higher than expected.


Assuntos
Mudança Climática , Cipriniformes/genética , Variação Genética , Genética Populacional , Animais , DNA Mitocondrial/genética , Evolução Molecular , Água Doce , Hong Kong , Filogenia , Filogeografia
5.
Dis Aquat Organ ; 101(3): 207-15, 2012 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-23324417

RESUMO

A multi-laboratory broth microdilution method trial was performed to standardize the specialized test conditions required for the fish pathogens Flavobacterium columnare and F. psychrophilum. Nine laboratories tested the quality control (QC) strains Escherichia coli ATCC 25922 and Aeromonas salmonicida subsp. salmonicida ATCC 33658 against 10 antimicrobials (ampicillin, enrofloxacin, erythromycin, florfenicol, flumequine, gentamicin, ormetoprim/sulfadimethoxine, oxolinic acid, oxytetracycline, and trimethoprim/sulfamethoxazole) in diluted (4 g l-1) cation-adjusted Mueller-Hinton broth incubated at 28 and 18°C for 44-48 and 92-96 h, respectively. QC ranges were set for 9 of the 10 antimicrobials. Most of the minimal inhibitory concentration (MIC) distributions (16 of 18, 9 drugs at both temperatures) for A. salmonicida ATCC 33658 were centered on a single median MIC ± 1 two-fold drug dilution resulting in a QC range that spanned 3 dilutions. More of the E. coli ATCC 25922 MIC distributions (7 of 16) were centered between 2 MIC dilutions requiring a QC range that spanned 4 dilutions. A QC range could not be determined for E. coli ATCC 25922 against 2 antimicrobials at the low temperature. These data and their associated QC ranges have been approved by the Clinical and Laboratory Standards Institute (CLSI), and will be included in the next edition of the CLSI M49-A Guideline. This method represents the first standardized reference method for testing fish pathogenic Flavobacterium spp.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Flavobacterium/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Animais , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Trials ; 22(1): 84, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33482890

RESUMO

BACKGROUND: The lack of approved treatments for the majority of rare diseases is reflective of the unique challenges of orphan drug development. Novel methodologies, including new functionally relevant endpoints, are needed to render the development process more feasible and appropriate for these rare populations and thereby expedite the approval of promising treatments to address patients' high unmet medical need. Here, we describe the development of an innovative master protocol and primary outcome assessment to investigate the modified amino acid N-acetyl-L-leucine (Sponsor Code: IB1001) in three separate, multinational, phase II trials for three ultra-rare, autosomal-recessive, neurodegenerative disorders: Niemann-Pick disease type C (NPC), GM2 gangliosidoses (Tay-Sachs and Sandhoff disease; "GM2"), and ataxia telangiectasia (A-T). METHODS/DESIGN: The innovative IB1001 master protocol and novel CI-CS primary endpoints were developed through a close collaboration between the Industry Sponsor, Key Opinion Leaders, representatives of the Patient Communities, and National Regulatory Authorities. As a result, the open-label, rater-blinded study design is considerate of the practical limitations of recruitment and retention of subjects in these ultra-orphan populations. The novel primary endpoint, the Clinical Impression of Change in Severity© (CI-CS), accommodates the heterogenous clinical presentation of NPC, GM2, and A-T: at screening, the principal investigator appoints for each patient a primary anchor test (either the 8-m walk test (8MWT) or 9-hole peg test of the dominant hand (9HPT-D)) based on his/her unique clinical symptoms. The anchor tests are videoed in a standardized manner at each visit to capture all aspects related to the patient's functional performance. The CI-CS assessment is ultimately performed by independent, blinded raters who compare videos of the primary anchor test from three periods: baseline, the end of treatment, and the end of a post-treatment washout. Blinded to the time point of each video, the raters make an objective comparison scored on a 7-point Likert scale of the change in the severity of the patient's neurological signs and symptoms from video A to video B. To investigate both the symptomatic and disease-modifying effects of treatment, N-acetyl-L-leucine is assessed during two treatment sequences: a 6-week parent study and 1-year extension phase. DISCUSSION: The novel CI-CS assessment, developed through a collaboration of all stakeholders, is advantageous in that it better ensures the primary endpoint is functionally relevant for each patient, is able to capture small but meaningful clinical changes critical to the patients' quality of life (fine-motor skills; gait), and blinds the primary outcome assessment. The results of these three trials will inform whether N-acetyl-L-leucine is an effective treatment for NPC, GM2, and A-T and can also serve as a new therapeutic paradigm for the development of future treatments for other orphan diseases. TRIAL REGISTRATION: The three trials (IB1001-201 for Niemann-Pick disease type C (NPC), IB1001-202 for GM2 gangliosidoses (Tay-Sachs and Sandhoff), IB1001-203 for ataxia telangiectasia (A-T)) have been registered at www.clinicaltrials.gov (NCT03759639; NCT03759665; NCT03759678), www.clinicaltrialsregister.eu (EudraCT: 2018-004331-71; 2018-004406-25; 2018-004407-39), and https://www.germanctr.de (DR KS-ID: DRKS00016567; DRKS00017539; DRKS00020511).


Assuntos
Ataxia Telangiectasia , Gangliosidoses GM2 , Doenças Neurodegenerativas , Feminino , Humanos , Leucina , Masculino , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/tratamento farmacológico , Qualidade de Vida
7.
Am J Transplant ; 10(5): 1276-83, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20353467

RESUMO

To evaluate the efficacy of stent placement in the treatment of portal vein (PV) stenosis or occlusion in living donor liver transplant (LDLT) recipients, 468 LDLT records were reviewed. Sixteen (10 PV occlusions and 6 stenoses) recipients (age range, 8 months-59 years) were referred for possible interventional angioplasty (dilatation and/or stent) procedures. Stent placement was attempted in all. The approaches used were percutaneous transhepatic (n = 10), percutaneous transsplenic (n = 4), and intraoperative (n = 2). Technical success was achieved in 11 of 16 patients (68.8%). The sizes of the stents used varied from 7 mm to 10 mm in diameter. In the five unsuccessful patients, long-term complete occlusion of the PV with cavernous transformation precluded catherterization. The mean follow-up was 12 months (range, 3-24). The PV stent patency rate was 90.9% (10/11). Rethrombosis and occlusion of the stent and PV occurred in a single recipient who had a cryoperserved vascular graft to reconstruct the PV during the LDLT operation. PV occlusion of >1 year with cavernous transformation seemed to be a factor causing technical failure. In conclusion, early treatment of PV stenosis and occlusion by stenting is an effective treatment in LDLT. Percutaneous transhepatic and transsplenic, and intraoperative techniques are effective approaches depending on the situation.


Assuntos
Transplante de Fígado/efeitos adversos , Transplante de Fígado/métodos , Doadores Vivos , Veia Porta/cirurgia , Adulto , Vasos Sanguíneos , Criança , Pré-Escolar , Constrição Patológica/complicações , Constrição Patológica/diagnóstico por imagem , Constrição Patológica/cirurgia , Endoscopia Gastrointestinal/efeitos adversos , Humanos , Transplante de Fígado/diagnóstico por imagem , Veia Porta/diagnóstico por imagem , Radiografia , Stents/efeitos adversos , Resultado do Tratamento , Doenças Vasculares/complicações , Doenças Vasculares/diagnóstico por imagem , Doenças Vasculares/cirurgia , Veias/cirurgia
8.
Cell Mol Life Sci ; 66(5): 900-8, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19153666

RESUMO

The acrosome reaction has long been thought to be induced by the zona pellucida. Here we report the identification and function of a novel human sperm glycosylphosphatidylinositol (GPI)-anchored membrane protein, NYD-SP8. The release of the protein during sperm-egg interaction and its binding to the cumulus, the first layer of egg investment, elicits cross-talk between the gametes and produces calcium dependant release of progesterone, which lead to the acrosome reaction. An in vivo mouse model of NYD-SP8 immunization is also established showing a reduced fertility rate. Thus, contrary to accepted dogma, our study demonstrates for the first time that, prior to reaching the zona pellucida, sperm may release a surface protein that acts on the cumulus cells leading to the acrosome reaction, which may be important for determining the outcome of fertilization.


Assuntos
Reação Acrossômica/fisiologia , Comunicação Celular/fisiologia , Células do Cúmulo/metabolismo , Glicosilfosfatidilinositóis/metabolismo , Proteínas de Membrana/metabolismo , Espermatozoides/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/metabolismo , Antígenos de Superfície/genética , Antígenos de Superfície/metabolismo , Cálcio/metabolismo , Células do Cúmulo/citologia , Feminino , Fertilidade , Fertilização , Proteínas Ligadas por GPI , Glicosilfosfatidilinositóis/genética , Humanos , Masculino , Proteínas de Membrana/genética , Camundongos , Dados de Sequência Molecular , Oócitos/citologia , Oócitos/metabolismo , Progesterona/metabolismo , Alinhamento de Sequência , Espermatozoides/citologia , Distribuição Tecidual
9.
Artigo em Inglês | MEDLINE | ID: mdl-32982985

RESUMO

Introduction: Gestational Diabetes Mellitus (GDM) affects one in six births worldwide. Mothers with GDM have an increased risk of developing post-partum Type-2 Diabetes Mellitus (T2DM). However, their uptake of post-partum diabetes screening is suboptimal, including those in Singapore. Literature reports that the patient-doctor relationship, mothers' concerns about diabetes, and family-related practicalities are key factors influencing the uptake of such screening. However, we postulate additional factors related to local society, healthcare system, and policies in influencing post-partum diabetes screening among mothers with GDM. Aim: The qualitative research study aimed to explore the facilitators and barriers to post-partum diabetes screening among mothers with GDM in an Asian community. Methods: In-depth interviews were carried out on mothers with GDM at a public primary care clinic in Singapore. Mothers were recruited from those who brought their child for vaccination appointments and their informed consent was obtained. Both mothers who completed post-partum diabetes screening within 12 weeks after childbirth and those who did not were purposively recruited. The social ecological model (SEM) provides the theoretical framework to identify facilitators and barriers at the individual, interpersonal, organizational, and policy levels. Results: Twenty multi-ethnic Asian mothers with GDM were interviewed. At the individual and interpersonal level, self-perceived risk of developing T2DM, understanding the need for screening and the benefits of early diagnosis, availability of confinement nanny in Chinese family, alternate caregivers, emotional, and peer support facilitated post-partum diabetes screening. Barriers included fear of the diagnosis and its consequences, preference for personal attention and care to child, failure to find trusted caregiver, competing priorities, and unpleasant experiences with the oral glucose tolerance test. At the organizational and public policy level, bundling of scheduled appointments, and standardization of procedure eased screening but uptake was hindered by inconvenient testing locations, variable post-partum care practices and advice in the recommendations for diabetes screening. Conclusion: Based on the SEM, facilitators and barriers towards post-partum diabetes screening exist at multiple levels, with some contextualized to local factors. Interventions to improve its uptake should be multi-pronged, targeting not only at personal but also familial, health system, and policy factors to ensure higher level of success.


Assuntos
Glicemia/análise , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Gestacional/diagnóstico , Período Pós-Parto , Diabetes Mellitus Tipo 2/sangue , Diabetes Gestacional/sangue , Feminino , Teste de Tolerância a Glucose , Acessibilidade aos Serviços de Saúde , Humanos , Programas de Rastreamento , Mães , Gravidez , Pesquisa Qualitativa , Singapura
10.
Am J Transplant ; 9(6): 1382-8, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19459827

RESUMO

Optimal portal flow is one of the essentials in adequate liver function, graft regeneration and outcome of the graft after right lobe adult living donor liver transplantation (ALDLT). The relations among factors that cause sufficient liver graft regeneration are still unclear. The aim of this study is to evaluate the potential predisposing factors that encourage liver graft regeneration after ALDLT. The study population consisted of right lobe ALDLT recipients from Chang Gung Memorial Hospital-Kaohsiung Medical Center, Taiwan. The records, preoperative images, postoperative Doppler ultrasound evaluation and computed tomography studies performed 6 months after transplant were reviewed. The volume of the graft 6 months after transplant divided by the standard liver volume was calculated as the regeneration ratio. The predisposing risk factors were compiled from statistical analyses and included age, recipient body weight, native liver disease, spleen size before transplant, patency of the hepatic venous graft, graft weight-to-recipient weight ratio (GRWR), posttransplant portal flow, vascular and biliary complications and rejection. One hundred forty-five recipients were enrolled in this study. The liver graft regeneration ratio was 91.2 +/- 12.6% (range, 58-151). The size of the spleen (p = 0.00015), total portal flow and GRWR (p = 0.005) were linearly correlated with the regeneration rate. Patency of the hepatic venous tributary reconstructed was positively correlated to graft regeneration and was statistically significant (p = 0.017). Splenic artery ligation was advantageous to promote liver regeneration in specific cases but splenectomy did not show any positive advantage. Spleen size is a major factor contributing to portal flow and may directly trigger regeneration after transplant. Control of sufficient portal flow and adequate hepatic outflow are important factors in graft regeneration.


Assuntos
Regeneração Hepática , Transplante de Fígado/métodos , Doadores Vivos , Adulto , Idoso , Feminino , Veias Hepáticas/transplante , Humanos , Fígado/irrigação sanguínea , Fígado/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler
11.
Mol Phylogenet Evol ; 51(2): 304-11, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19405196

RESUMO

Spiny lobsters (family Palinuridae) are economically important marine animals that have been the subject of a considerable amount of research. However, the phylogeny of this group remains disputed. Morphological analyses have not been able to resolve the relationships of the various members of the group, and no agreement has yet been reached on its phylogeny as indicated by the different gene trees reported to date. In the present study, we attempt to reconstruct the phylogeny of Palinuridae and its allies using sequences from three nuclear protein-coding genes (phosphoenolpyruvate carboxykinase, sodium-potassium ATPase alpha-subunit and histone 3). The inferred topology receives strong nodal support for most of the branches. The family Palinuridae is found to be paraphyletic with the polyphyletic Synaxidae nested within it. Stridentes forms a monophyletic assemblage, indicating that the stridulating sound producing organ evolved only once in the spiny lobsters. By contrast, Silentes is paraphyletic, as Palinurellus is more closely related to Stridentes than to other Silentes genera. The three genera restricted to the southern high latitudes (Jasus, Projasus and Sagmariasus) constitute the basal lineages in the spiny lobsters, suggesting a Southern Hemisphere origin for the group. Subsequent diversification appears to have been driven by the closure of the Tethys Sea and the formation of the Antarctic circumpolar current, which isolated the northern and southern taxa. Contrary to an earlier hypothesis that postulated evolution from a deep-sea ancestral stock, the shallow-water genus Panulirus is the basal taxon in Stridentes, while the deep-sea genera Puerulus and Linuparus are found to be derived. This indicates that the spiny lobsters invaded deep-sea habitats from the shallower water rocky reefs and then radiated. Our results suggest that Synaxidae is not a valid family, and should be considered to be synonymous with Palinuridae. We also found that the previously proposed subgenera Sagmariasus and Nupalirus are genetically highly diverged, and both warrant a generic status.


Assuntos
Evolução Molecular , Palinuridae/genética , Filogenia , Animais , Núcleo Celular/genética , Especiação Genética , Modelos Genéticos , Palinuridae/anatomia & histologia , Palinuridae/classificação , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da Espécie
12.
Vet Clin Pathol ; 38(3): 343-7, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19490567

RESUMO

A 15-year-old female Simmental cross-breed cow was presented to the Purdue University Veterinary Teaching Hospital for evaluation of a perifemoral soft tissue mass. Impression smears made from an excisional biopsy contained a population of pleomorphic mesenchymal cells with abundant, periodic acid-Schiff-positive (PAS), intracytoplasmic granular material, and rare elongated multinucleated cells consistent with strap-like cells. A second population of small round cells suggestive of lymphocytes or progenitor cells was also noted. A cytologic diagnosis of sarcoma was made, with rhabdomyosarcoma considered most likely based on the large amount of PAS-positive material (presumed to be glycogen) and the rare strap-like cells. Histopathologic sections contained an unencapsulated, densely cellular neoplasm composed of haphazardly arranged highly pleomorphic mesenchymal cells and a few small round cells. The mesenchymal cells were positive for vimentin, non-specific muscle actin, and myoglobin, and negative for phosphotungstic acid-hematoxylin, smooth muscle actin, and desmin. Glycogen granules were confirmed by transmission electron microscopy. A diagnosis of pleomorphic rhabdomyosarcoma was made. While cytologic findings may suggest rhabdomyosarcoma, cytologic features can be highly variable, and a definitive diagnosis usually requires cytochemical and immunohistochemical staining.


Assuntos
Doenças dos Bovinos/patologia , Neoplasias Musculares/veterinária , Rabdomiossarcoma/veterinária , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Feminino , Membro Posterior/patologia , Neoplasias Musculares/diagnóstico , Neoplasias Musculares/patologia , Gravidez , Rabdomiossarcoma/patologia
13.
Nurse Educ Pract ; 38: 112-119, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31254943

RESUMO

Nurse preceptors play an important role in supporting newly qualified nurses during transition periods. However, limited attention is given to the needs and experience of nurse preceptors with expected responsibilities. This study aimed to examine the perceived needs of nurse preceptors in three public acute hospitals by using a sequential mixed method approach conducted between March and August 2017. A questionnaire that comprised socio-demographic data, Clinical Teaching Behaviour Inventory (CTBI), and RN Preceptor Learning Needs Assessment, was distributed to all nurse preceptors. Semi-structured qualitative interviews were conducted with a purposive sample of 10 informants to complement the quantitative findings. We received 260 completed questionnaires, giving a response rate of 78.8%. The highest mean CTBI domain score was "Using appropriate teaching strategies" (Mean = 3.65, SD = 0.56), whereas the lowest was "Providing feedback and evaluation" (Mean = 3.51, SD = 0.60). The top five topics identified as the most important in nurse preceptor training were critical thinking, prioritising, teaching techniques, conflict management and teamwork. Qualitative findings revealed that the informants experienced tension with their dual roles and strained relationships with co-workers. The expectations of the informants for support were recognition from management level and highlighting coaching tactics, reciprocal learning and collegiate support.


Assuntos
Mentores/psicologia , Avaliação das Necessidades , Preceptoria/métodos , Adulto , Atitude do Pessoal de Saúde , Estudos Transversais , Feminino , Grupos Focais/métodos , Hong Kong , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Inquéritos e Questionários
14.
J Vet Intern Med ; 33(3): 1260-1265, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31008541

RESUMO

BACKGROUND: Gastric wall edema has not been reported as a complication of acute pancreatitis in dogs. OBJECTIVE: To describe the ultrasonographic features of gastric wall thickening in dogs with acute pancreatitis. ANIMALS: Fourteen dogs with ultrasonographic evidence and clinical diagnosis of acute pancreatitis, with ultrasonographic evidence of increased gastric wall thickness (>5 mm). METHODS: A retrospective search in the medical records from 2014 to 2016 was performed to identify dogs that had ultrasonographic evidence of acute pancreatitis, that had increased thickness of the gastric wall and that were diagnosed with acute pancreatitis clinically. The gastric wall changes such as thickness, layering appearance, echogenicity, distribution of lesions, and perigastric changes were recorded. Serial ultrasonographic examination and histopathological findings were recorded if available. RESULTS: Mean gastric wall thickness was 9.9 ± 4.0 mm (SD). A complete loss of wall layering was observed in 2 dogs. Thickening of the submucosal layer was observed in 12 dogs, and 5 of them had concurrent muscularis layer thickening. The echogenicity of thickened submucosal layer was intermediate hyperechoic. Lacy appearances were present within the thickened submucosal layer in 7 dogs and in the muscularis layer of 1 dog. Thickening was focal in 12 dogs and adjacent to the diseased pancreas. Subsequent resolution of gastric wall thickening was observed in 3 dogs (range 3-28 days) via follow-up ultrasound. One dog underwent necropsy, and gastric wall edema was confirmed histopathologically. CONCLUSIONS AND CLINICAL IMPORTANCE: Findings indicated that gastric wall thickening presumably because of edema could be a complication of acute pancreatitis.


Assuntos
Doenças do Cão/diagnóstico por imagem , Pancreatite/veterinária , Gastropatias/veterinária , Animais , Cães , Edema/diagnóstico por imagem , Edema/veterinária , Pancreatite/complicações , Pancreatite/diagnóstico por imagem , Estudos Retrospectivos , Estômago/patologia , Gastropatias/diagnóstico por imagem , Ultrassonografia/veterinária
15.
Mol Phylogenet Evol ; 48(1): 359-68, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18501643

RESUMO

The phylogeny of Decapoda is contentious and many hypotheses have been proposed based on morphological cladistic analyses. Recent molecular studies, however, yielded contrasting results despite their use of similar data (nuclear and mitochondrial rDNA). Here we present the first application of two nuclear protein-coding genes, phosphoenolpyruvate carboxykinase and sodium-potassium ATPase alpha-subunit, to reconstruct the phylogeny of major infraorders within Decapoda. A total of 64 species representing all infraorders of Pleocyemata were analyzed with five species from Dendrobranchiata as outgroups. Maximum likelihood and Bayesian inference reveal that the Reptantia and all but one infraorder are monophyletic. Thalassinidea, however, is polyphyletic. The nodal support for most of the infraordinal and inter-familial relationships is high. Stenopodidea and Caridea form a clade sister to Reptantia, which comprises two major clades. The first clade, consisting of Astacidea, Achelata, Polychelida and three thalassinidean families (Axiidae, Calocarididae and Eiconaxiidae), corresponds essentially to the old taxon suborder Macrura Reptantia. Polychelida nests within Macrura Reptantia instead of being the most basal reptant as suggested in previous studies. The high level of morphological and genetic divergence of Polychelida from Achelata and Astacidea justifies its infraorder status. The second major reptant clade consists of Anomura, Brachyura and two thalassindean families (Thalassinidae and Upogebiidae). Anomura and Brachyura form Meiura, with moderate support. Notably thalassinidean families are sister to both major reptant clades, suggesting that the stem lineage reptants were thalassinidean-like. Moreover, some families (e.g. Nephropidae, Diogenidae, Paguridae) are paraphyletic, warranting further studies to evaluate their status. The present study ably demonstrates the utility of nuclear protein-coding genes in phylogenetic inference in decapods. The topologies obtained are robust and the two molecular markers are informative across a wide range of taxonomic levels. We propose that nuclear protein-coding genes should constitute core markers for future phylogenetic studies of decapods, especially for higher systematics.


Assuntos
Decápodes/classificação , Decápodes/genética , Animais , Evolução Biológica , Carboxiliases/genética , Decápodes/enzimologia , Filogenia , ATPase Trocadora de Sódio-Potássio/genética
16.
Transplant Proc ; 40(8): 2460-2, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18929768

RESUMO

Accurate pretransplant evaluation of a potential donor in living donor liver transplantation (LDLT) is essential in preventing postoperative liver failure and optimizing safety. The aim of this study was to investigate the reasons for exclusion from donation of potential donors in adult LDLT. From September 2003 to June 2006, 266 potential donors were evaluated for 215 recipients: 220 potential donors for 176 adult recipients; 46 for 39 pediatric recipients. Imaging modalities including Doppler ultrasound, computerized tomography (CT), and magnetic resonance (MR) angiography provided vascular evaluation and MR cholangiopancreatography to evaluate biliary anatomy. Calculation of liver volume and assessment of steatosis were performed by enhanced and nonenhanced CT, respectively. In the adult group, only 83 (37.7%) potential donors were considered suitable for LDLT. Of the 137 unsuitable potential donors, 36 (26.2%) candidates were canceled because of recipient issues that included death of 15 recipients (10.9%), main portal vein thrombosis (8%), recipient condition beyond surgery (5%), and no indication for liver transplantation due to disease improvement (2%). The remaining 101 (73.8%) candidates who were excluded included steatosis (27.7%), an inadequate remnant volume (57.4%), small-for-size graft (8.9%), HLA-homozygous donor leading to one-way donor-recipient HLA match (3%), psychosocial problems (4%), as well as variations of hepatic artery (4%), portal vein (1%), and biliary system anatomy (5%). Anatomic considerations were not the main reason for exclusion of potential donors. An inadequate remnant liver volume (< 30%) is the crucial point for the adult LDLT decision.


Assuntos
Transplante de Fígado/métodos , Doadores Vivos , Cuidados Pré-Operatórios , Adulto , Artéria Hepática/diagnóstico por imagem , Humanos , Fígado/anatomia & histologia , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética , Seleção de Pacientes , Complicações Pós-Operatórias/prevenção & controle , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler
17.
Transplant Proc ; 40(8): 2478-80, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18929771

RESUMO

BACKGROUND: Liver transplantation is an important treatment option in the management of end-stage liver disease. Preoperative vascular evaluation plays an important role for a safe and successful operation, especially in pediatric patients undergoing living donor liver transplantation (LDLT). PURPOSE: The purpose of this study is to assess the usefulness and accuracy of Doppler ultrasound (US), computed tomographic angiography (CTA), and magnetic resonance angiography (MRA) in evaluating vascular anomalies in patients with biliary atresia (BA) undergoing LDLT. METHODS AND MATERIALS: Images of Doppler US, CTA, and MRA for preoperative vascular evaluation in 55 patients with BA undergoing LDLT were reviewed with the operative findings. RESULTS: All patients underwent preoperative US, CTA, and MRA. Pathologic portal vein (n = 18), interruption of the retrohepatic vena cava (n = 1), and aberrant right hepatic artery from the superior mesenteric artery (n = 2) were confirmed during the transplantation. The success rates of CTA and MRA in identifying vascular anomalies were 96% and 82%, respectively (P = .01). The sensitivity, specificity, and accuracy of Doppler US were 89%, 94%, and 92%, respectively. For CTA, it was 94%, 97%, and 96%, respectively; for MRA (including technical failure), it was 75%, 97%, and 89%, respectively. CONCLUSION: Doppler US serves as an initial assessment for vascular evaluation and has the advantage in determining vascular flow quantities. CTA and MRA are used for precise surgical planning. However, MRA has lower success and accuracy rates when compared with CTA (P = .01). Doppler US with CTA can provide accurate preoperative vascular imaging in patients with BA undergoing LDLT.


Assuntos
Atresia Biliar/cirurgia , Hepatectomia/métodos , Circulação Hepática/fisiologia , Transplante de Fígado/métodos , Doadores Vivos , Coleta de Tecidos e Órgãos/métodos , Adolescente , Criança , Pré-Escolar , Feminino , Artéria Hepática/diagnóstico por imagem , Artéria Hepática/patologia , Veias Hepáticas/diagnóstico por imagem , Veias Hepáticas/patologia , Humanos , Lactente , Transplante de Fígado/mortalidade , Masculino , Veia Porta/diagnóstico por imagem , Veia Porta/patologia , Cuidados Pré-Operatórios , Estudos Retrospectivos , Taxa de Sobrevida , Sobreviventes , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler
18.
Transplant Proc ; 40(8): 2481-3, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18929772

RESUMO

INTRODUCTION: The purpose of this study was to evaluate the changes in liver fatty content and the volumes of liver and spleen after body weight reduction in potential living liver donors. MATERIALS AND METHODS: Twenty-three potential living donors had fatty livers at pretransplantation sonography and computed tomography (CT). All were advised to undergo body weight reduction by exercise and diet control. A percutaneous core liver biopsy was performed in segment 5 of the liver in 22 donors to evaluate the hepatic fat content before and after body weight reduction. We compared the changes in the liver CT attenuation values and volume changes in the left and right lobes of the liver and the spleen before and after body weight reduction. RESULTS: The mean (SD) body weight, body mass index, and fatty content of the liver biopsy specimens were 73 (17) kg, 26.8 (4.4), and 16.9% (12.7%), respectively, before body weight reduction and 70 (15) kg, 25.3 (3.8), and 6.6% (3.7%), respectively, thereafter. These changes were significant. The CT attenuation values of the left and right lobes of the liver and spleen were 54 (11), 51 (11), and 52 (5) HU, respectively, before body weight reduction and 60 (8), 58 (6), and 53 (5) HU, respectively, thereafter. The mean CT attenuation value of the left lateral segment was greater than that of the right lobe both before and after body weight reduction. The volume of the left and right lobes and spleen changed from 497 (129) cm3 to 452 (99) cm3, 927 (237) cm3 to 846 (173) cm3, and 185 (65) cm3 to 186 (63) cm3, respectively, thereafter. The right and left lobe volume change ratios were 7.0% (10.6%) and 7.6% (11.1%), respectively, but showed no significant difference. Twenty of the 23 candidates were able to donate part of their liver. CONCLUSION: Body weight reduction by exercise and diet control in potential living liver donors is effective to reduce the fatty content of the liver. Reversed percentage of the fatty content and volume of the liver was observed in these donors. The volumes of the right and left lobes of liver decreased significantly after body weight reduction. The volume changes were proportional.


Assuntos
Fígado Gorduroso/epidemiologia , Fígado/anatomia & histologia , Doadores Vivos , Baço/anatomia & histologia , Redução de Peso , Tecido Adiposo/anatomia & histologia , Tecido Adiposo/patologia , Adolescente , Biópsia , Índice de Massa Corporal , Peso Corporal , Fígado Gorduroso/patologia , Feminino , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Estudos Retrospectivos , Baço/patologia , Tomografia Computadorizada por Raios X
19.
Transplant Proc ; 40(8): 2515-6, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18929784

RESUMO

AIMS: Distal splenorenal shunt effectively controls bleeding from esophageal and gastric varices but has a different effect on liver transplantation. This study sought to develop an animal model in rats to mimic the recipient with a portosystemic shunt and to investigate its hemodynamic consequences on liver transplantation. METHODS: We prepared 5 groups of allogeneic or syngeneic rat liver transplantation models with versus without portosystemic shunt, to investigate its effects on graft survival and portal flow. To explore the effects of excessive portal flow on graft survival in small-for-size liver transplantation, we transplanted partial liver grafts into syngeneic recipients. RESULTS: In allogeneic combinations, graft survival among the shunt group was shortened compared with their control counterparts. The graft survival of the large shunt group was significantly lower than that of a small shunt or without shunt group in a syngeneic liver transplantation model. Portal blood pressure of the large shunt group was significantly lower than that of the small shunt group. In contrast, excessive portal flow resulted in dysfunction of liver graft in small-for-size liver transplantation. CONCLUSIONS: These results suggested that reduction in portal flow by portosystemic shunt lead to an acceleration of acute rejection and subsequent liver graft dysfunction, but it may be applicable to regulate the excessive portal flow in small-for-size transplantations. This study showed a valuable model mimicking the recipient with a portosystemic shunt.


Assuntos
Sobrevivência de Enxerto/fisiologia , Transplante de Fígado/fisiologia , Derivação Portossistêmica Cirúrgica/métodos , Animais , Transplante de Fígado/métodos , Modelos Animais , Ratos , Ratos Endogâmicos Lew , Ratos Endogâmicos , Transplante Homólogo , Transplante Isogênico
20.
Transplant Proc ; 40(8): 2534-6, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18929792

RESUMO

OBJECTIVE: Early diagnosis and appropriate management of vascular and biliary complications after living donor liver transplantation (LDLT) result in longer survival. We report our institutional experience regarding radiological management of these complications among patients with biliary atresia (BA) who underwent LDLT. METHODS: We analyzed the records of 116 children. All patients underwent Doppler ultrasound (US) at operation, daily for the first 2 postoperative weeks, and when necessary thereafter. After primary evaluation using US, the definite diagnosis of postoperative complication was confirmed using computed tomography, magnetic resonance imaging, and/or operation. RESULTS: There were 61 boys and 55 girls. The overall mean age was 2.69 years. The overall mean preoperative weight and height were 13.06 kg and 83.79 cm, respectively. There were 28 (24.13%) biliary and vascular complications. These were cases of biliary stricture (n = 5), bile leakage (n = 3), hepatic artery stenosis (n = 6), hepatic vein stenosis (n = 4), and portal vein thrombosis (n = 17). The diagnostic accuracy of US in detecting biliary complication, hepatic artery stenosis, hepatic venous stenosis, and portal vein thrombosis was 95.69%, 97.41%, 100%, and 100%, respectively. US in combination with multiple imaging modalities and clinical suspicion resulted in 100% diagnostic accuracy. Percutaneous transhepatic cholangiography, thrombolysis, balloon angioplasty, and stent placement were performed for the complications noted. There was an early mortality due to multiple-organ failure after failed radiological invention and subsequent surgical management. CONCLUSIONS: Doppler US is accurate in detecting postoperative complications after pediatric LDLT for BA. Radiological interventions for vascular and biliary complications are effective and safe alternatives to reconstructive surgery.


Assuntos
Atresia Biliar/complicações , Doenças da Vesícula Biliar/radioterapia , Transplante de Fígado/efeitos adversos , Complicações Pós-Operatórias/classificação , Doenças Vasculares/radioterapia , Criança , Pré-Escolar , Feminino , Doenças da Vesícula Biliar/diagnóstico , Humanos , Masculino , Estudos Retrospectivos , Resultado do Tratamento , Doenças Vasculares/diagnóstico
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