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31.
Ankle fusion: a retrospective review 总被引:1,自引:0,他引:1
A D Aaron 《Orthopedics》1990,13(11):1249-1254
The results of ankle fusion were reviewed in 26 patients who underwent 32 arthrodesis procedures. Posttraumatic degenerative arthritis was the most common indication for fusion (54%). Crossed cancellous screws were the primary method employed (43%), with an external fixator being used in 22% of cases. The overall union rate was 81%, with both crossed cancellous screws and external fixation attaining the best results (86%). Nonunion and infection were the most frequent complications. Progression of subtalar arthritis was demonstrated in 29% of patients postoperatively. Seventy-eight percent of patients graded extremity appearance as excellent or good, with the majority being able to return to work. 相似文献
32.
OBJECTIVE: To determine clinical utility of fine needle aspiration (FNA) in parotid neoplasia. STUDY DESIGN AND SETTING: Retrospective cohort study. METHODS: FNA and final pathology data were reviewed for patients who underwent parotidectomy for malignancy. Surgical outcomes were compared between patients with malignant cytology versus nonmalignant/nondiagnostic cytology. RESULTS: Twenty-seven of 33 primary malignant parotid lesions underwent FNA. Seventeen (63.0%) patients were diagnosed with cancer on FNA. The remaining 16 patients did not undergo FNA (n = 6), had a nondiagnostic FNA specimen (n = 5), or were incorrectly diagnosed with a benign lesion (n = 5). Patients who went on to parotidectomy with intent to treat malignancy based on FNA had significantly higher rates of upfront neck dissections (47.1% vs 12.5%, P = 0.036) as well as clear pathological margins (70.6% vs 31.3%, P = 0.027) vs those with nonmalignant FNA diagnoses. CONCLUSIONS: Preoperative FNA diagnosis of malignancy improves surgical treatment of parotid cancer. SIGNIFICANCE: FNA in the evaluation of parotid masses should strongly be considered. 相似文献
33.
Dr. James G. Jarvis Aaron Marlow Louis J. Lawton William M. J. McIntyre 《Operative Orthopadie und Traumatologie》1998,10(2):117-124
Zusammenfassung
Operationsziel überdachung des Femurkopfes bei Hüftgelenkdysplasie.
Indikationen Dysplastisches Acetabulum bei Patienten mit neuromuskul?ren und nichtneuromuskul?ren Erkrankungen.
übergro?es, flaches Acetabulum.
Fehlen einer lateralen und kranialen überdachung.
Kontraindikationen Y-Fuge geschlossen, Wachstum abgeschlossen.
Stark verformter Femurkopf.
Operationstechnik Modifizierter Zugang nach Salter/Smith-Petersen. Freilegung und Teilung der Apophyse des Beckenkammes mit einem Messer. Freilegung
der Darmbeinschaufel. Osteotomie der ?u?eren Wand des Iliums; sie wird vorsichtig mit Hilfe eines gebogenen mei?els nach unten
gebogen und in dieser Stellung durch Einsetzen von trikortikalen Beckenkammsp?nen gehalten. Eine Osteosynthese ist nicht notwendig.
Becken-Bein-Gipsverband mit Einschlu? des gegenseitigen Oberschenkels für sechs Wochen.
Ergebnisse Zwischen 1987 und 1997 wurden 26 Hüften von 23 Patienten operiert. überwiegend handelte es sich um Kinder mit spastischen
Paresen. Folgende zus?tzliche Eingriffe wurden vorgenommen: Offene Reposition zehnmal, Femurosteotomie 18mal und Tenotomien
sowie Muskelabl?sungen 15mal. Der Durchschnittswert des azetabul?ren Index verbesserte sich von 32° auf 22°, der durchschnittliche
Wert des Kopfzentrum-Pfannenrand-Winkels von −25° auf 22° und der durchschnittliche Migrationsindex von 62% auf 69%. Als Komplikationen
wurden beobachtet: eine erneute Subluxation, ein frühzeitiger Verschlu? des Y-Knorpels, eine Fraktur des anderen Femur, einmal
heterotope Ossifikationen und einmal eine Infektion der Harnwege. 相似文献
34.
Israel Zelikovic Shermine Dabbagh Aaron L. Friedman David T. Uehling Russell W. Chesney 《Pediatric nephrology (Berlin, Germany)》1988,2(4):512-514
A boy aged 4.5 years with prune-belly syndrome (PBS) and associated urethral stenosis, oligohydramnios, imperforate anus and vesicosigmoid fustula is described. In contrast to the anticipated poor prognosis, vesicostomy and divided transverse colostomy performed after birth followed by prophylaxis of infection and bicarbonate supplementation have resulted in a good outcome. The vesicosigmoid fistula might have served in utero as a natural diversion protecting from pressure-induced renal damage. It is suggested that the main determinant of prognosis in PBS is the presence and degree of kidney dysplasia at birth as reflected by the neonatal renal function after performance of an indicated urinary diversion procedure rather than the presence of severe associated anomalies.Supported in part by grants from the National Institute of Health AM 37223-01 and the Medical School and Graduate School Research Committees of the University of Wisconsin and a Research Career Development Award KO4 AM 00421 (RWC), by the Pearl M. Stetler Foundation (SD) and by a National Kidney Foundation fellowship (IZ) 相似文献
35.
In his recent formulations of rational emotive therapy (RET), Ellis (1985) has increasingly emphasized what he believes to be the central role of necessitous thinking or musturbation in the development of depression. In his most recent article (Ellis, 1987), he suggests that necessitous thinking is the primary cognitive component of depression and that RET stands alone in its recognition of the role of this cognitive element. The present study addressed three issues raised by Ellis's paper: (1) Clarify whether necessitous thinking has been neglected by other cognitive theorists, (2) test empirically the role of necessitou thinking in depression relative to other established cognitive constructs, e.g., the cognitive triad (Beck, 1967), and (3) determine whether necessitous thinking is particularly salient in depression as compared with other forms of psychopathology. It was predicted that necessitous thinking would be found in other forms of psychology in addition to depression, and this was confirmed. The results are discussed as highlighting the importance of empirically testing theoretical predictions.From the Foundation for Cognitive Therapy. 相似文献
36.
Karen W. Gripp Lindsey A. Morse Marni Axelrad Kathryn C. Chatfield Aaron Chidekel William Dobyns Daniel Doyle Bronwyn Kerr Angela E. Lin David D. Schwartz Barbara J. Sibbles Dawn Siegel Suma P. Shankar David A. Stevenson Mihir M. Thacker K. Nicole Weaver Sue M. White Katherine A. Rauen 《American journal of medical genetics. Part A》2019,179(9):1725-1744
Costello syndrome (CS) is a RASopathy caused by activating germline mutations in HRAS. Due to ubiquitous HRAS gene expression, CS affects multiple organ systems and individuals are predisposed to cancer. Individuals with CS may have distinctive craniofacial features, cardiac anomalies, growth and developmental delays, as well as dermatological, orthopedic, ocular, and neurological issues; however, considerable overlap with other RASopathies exists. Medical evaluation requires an understanding of the multifaceted phenotype. Subspecialists may have limited experience in caring for these individuals because of the rarity of CS. Furthermore, the phenotypic presentation may vary with the underlying genotype. These guidelines were developed by an interdisciplinary team of experts in order to encourage timely health care practices and provide medical management guidelines for the primary and specialty care provider, as well as for the families and affected individuals across their lifespan. These guidelines are based on expert opinion and do not represent evidence‐based guidelines due to the lack of data for this rare condition. 相似文献
37.
Aaron Ettenberg André Laferrière Peter M. Milner Norman White 《Physiology & behavior》1981,27(4):641-647
The hypothesis that responding contributes to the reward value of brain stimulation was tested in two novel experimental paradigms. In the first experiment rats lever-presssed for rewarding brain stimulation during 90 sec periods. After each period the lever automatically retracted and experimenter-administered stimulation (EAS) was presented at the same rate and current parameters as during the self-stimulation (SS). The rats could demonstrate a preference for SS (vs EAS) by pressing a reset lever on the opposite wall of the test chamber. This action terminated the EAS and reinstated the SS-lever for an additional 90 sec. Results showed that the rats preferred to respond for stimulation than to have that same stimulation administered by the experimenter. This was true even when a signal preceded each train of EAS or when subjects had a great deal of previous EAS experience. In the second experiment conditioned taste preferences were observed following novel taste/SS pairings but not following novel taste/EAS pairings. The data from these two experiments suggest that responding contributes to the rewarding value of brain stimulation. 相似文献
38.
Stessman J Maaravi Y Hammerman-Rozenberg R Cohen A Nemanov L Gritsenko I Gruberman N Ebstein RP 《Mechanisms of ageing and development》2005,126(2):333-339
In an exploratory study, 11 common polymorphisms were examined for contributing to longevity including: apolipoprotein E (apoE), methylenetetrahydrofolate reductase (MTHFR), cathepsin D (CAD), superoxide dismutase 2 (SOD2), angiotensinogen (AGT) and insulin-like growth factor 2 (IGF2), Leiden factor 7, p53 oncogene, dopamine D4 receptor (DRD4) and the serotonin transporter (SERT). Genotype and allele frequencies of these genes were compared in 224 older (75 years) Jewish Jerusalem residents of Ashkenazi ethnicity to a group of 441 younger subjects (22 years). Nominally significant results provide suggestive evidence in the Ashkenazi group that apoE, MHTFR, SOD2, IGF2 ApaI, and factor VII are risk factors for a single outcome, survival to 75. Overall, the more genetically homogenous Ashkenazi ethnic group showed evidence for association in five genes examined suggesting that future studies in this population would gainfully focus on this ethnic group. 相似文献
39.
Tirthadipa Pradhan-Sundd Silvia Liu Sucha Singh Minakshi Poddar Sungjin Ko Aaron Bell Jonathan Franks Ian Huck Donna Stolz Udayan Apte Sarangarajan Ranganathan Kari Nejak-Bowen Satdarshan P. Monga 《The American journal of pathology》2021,191(5):885-901
Hepatocytes are highly polarized epithelia. Loss of hepatocyte polarity is associated with various liver diseases, including cholestasis. However, the molecular underpinnings of hepatocyte polarization remain poorly understood. Loss of β-catenin at adherens junctions is compensated by γ-catenin and dual loss of both catenins in double knockouts (DKOs) in mice liver leads to progressive intrahepatic cholestasis. However, the clinical relevance of this observation, and further phenotypic characterization of the phenotype, is important. Herein, simultaneous loss of β-catenin and γ-catenin was identified in a subset of liver samples from patients of progressive familial intrahepatic cholestasis and primary sclerosing cholangitis. Hepatocytes in DKO mice exhibited defects in apical-basolateral localization of polarity proteins, impaired bile canaliculi formation, and loss of microvilli. Loss of polarity in DKO livers manifested as epithelial-mesenchymal transition, increased hepatocyte proliferation, and suppression of hepatocyte differentiation, which was associated with up-regulation of transforming growth factor-β signaling and repression of hepatocyte nuclear factor 4α expression and activity. In conclusion, concomitant loss of the two catenins in the liver may play a pathogenic role in subsets of cholangiopathies. The findings also support a previously unknown role of β-catenin and γ-catenin in the maintenance of hepatocyte polarity. Improved understanding of the regulation of hepatocyte polarization processes by β-catenin and γ-catenin may potentially benefit development of new therapies for cholestasis.A hallmark of epithelial cells is polarization, which is achieved by the orchestration of external cues, such as cellular contact, extracellular matrix, signal transduction, growth factors, and spatial organization.1 Hepatocytes in the liver show a unique polarity by forming several apical and basolateral poles within a cell.2 The apical poles of adjacent hepatocytes form a continuous network of bile canaliculi into which bile is secreted, whereas the basolateral membrane domain forms the sinusoidal pole, which secretes various components, such as proteins or drugs, into the blood circulation.3 Loss of hepatic polarity has been associated with several cholestatic and developmental disorders, including progressive familial intrahepatic cholestasis (PFIC) and primary sclerosing cholangitis (PSC).4,5 Although the molecular mechanisms governing hepatocyte polarity have been extensively studied in the in vitro systems, there is still a significant gap in our understanding of how polarity is established within the context of tissue during development or maintained during homeostasis.6,7 Similarly, the molecular pathways contributing to hepatic polarity are not entirely understood, and a better comprehension of hepatic polarity regulation is thus warranted.Previous studies have confirmed the role of hepatocellular junctions, such as tight and gap junctions, in the maintenance of hepatocyte polarity.8,9 Studies done in vitro and in vivo have shown that loss of junctional proteins, such as zonula occludens protein (ZO)-1, junctional adhesion molecule-A, and claudins, lead to impairment of polarity and distorted bile canaliculi formation.10, 11, 12, 13 In addition, proteins involved in tight junction assembly, such as liver kinase B1, are also involved in polarity maintenance.14 Among adherens junction proteins, various in vitro cell culture models have confirmed the role of E-cadherin in the regulation of hepatocyte polarity, possibly through its interaction with β-catenin.15,16 However, there is a lack of an in vivo model to study the role of adherens junction proteins in hepatocyte polarity and their misexpression contributing to various liver diseases.β-Catenin plays diverse functions in the liver during development, regeneration, zonation, and tumorigenesis.17, 18, 19 The relative contribution of β-catenin as part of the adherens junction is challenging to study because like in other tissues, γ-catenin compensates for the β-catenin loss in the liver.20,21 To address this redundancy, we previously reported a hepatocyte-specific -catenin and γ-catenin double-knockout (DKO) mouse model was reported.22 Simultaneous deletion of β-catenin and γ-catenin in mice livers led to cholestasis, partially through the breach of cell-cell junctions. However, more comprehensive understanding of the molecular underpinnings of the phenotype is needed.In the current study, prior preclinical findings of dual β-catenin and γ-catenin loss were extended to a subset of PFIC and PSC patients. In vivo studies using the murine model with hepatocyte-specific dual loss of β-catenin and γ-catenin showed complete loss of hepatocyte polarity compared to the wild-type controls (CONs). Loss of polarity in DKO liver was accompanied by epithelial-mesenchymal transition (EMT), activation of transforming growth factor (TGF)-β signaling, and reduced expression of hepatocyte nuclear factor 4α (HNF4α). Our findings suggest that β-catenin and γ-catenin and in turn adherens junction integrity, are critical for the maintenance of hepatocyte polarity, and any perturbations in this process can contribute to the pathogenesis of cholestatic liver disease. 相似文献
40.
Aaron A. Vogan S. Lorena Ament-Velsquez Eric Bastiaans Ola Wallerman Sven J. Saupe Alexander Suh Hanna Johannesson 《Genome research》2021,31(5):789
The genomes of eukaryotes are full of parasitic sequences known as transposable elements (TEs). Here, we report the discovery of a putative giant tyrosine-recombinase-mobilized DNA transposon, Enterprise, from the model fungus Podospora anserina. Previously, we described a large genomic feature called the Spok block which is notable due to the presence of meiotic drive genes of the Spok gene family. The Spok block ranges from 110 kb to 247 kb and can be present in at least four different genomic locations within P. anserina, despite what is an otherwise highly conserved genome structure. We propose that the reason for its varying positions is that the Spok block is not only capable of meiotic drive but is also capable of transposition. More precisely, the Spok block represents a unique case where the Enterprise has captured the Spoks, thereby parasitizing a resident genomic parasite to become a genomic hyperparasite. Furthermore, we demonstrate that Enterprise (without the Spoks) is found in other fungal lineages, where it can be as large as 70 kb. Lastly, we provide experimental evidence that the Spok block is deleterious, with detrimental effects on spore production in strains which carry it. This union of meiotic drivers and a transposon has created a selfish element of impressive size in Podospora, challenging our perception of how TEs influence genome evolution and broadening the horizons in terms of what the upper limit of transposition may be.Transposable elements (TEs) are major agents of change in eukaryotic genomes. Their ability to selfishly parasitize their host replication machinery has large impacts on both genome size and on gene regulation (Chénais et al. 2012). In extreme cases, TEs can contribute up to 85% of genomic content (Schnable et al. 2009), and expansion and reduction of TEs can result in rapid changes in both genome size and architecture (Haas et al. 2009; Möller and Stukenbrock 2017; Talla et al. 2017). Generally, TEs have small sizes (∼50–12,000 bp) and accomplish these large-scale changes through their sheer number. For example, there are ∼1.1 million Alu elements in the human genome, which have had a large impact on genome evolution (Jurka 2004; Bennett et al. 2008). The largest known cases among Class I retrotransposons are long terminal repeat (LTR) elements that can be as large as 30 kb, but among Class II DNA transposons, Mavericks/Polintons are known to grow as large as 40 kb through the capture of additional open reading frames (ORFs) (Arkhipova and Yushenova 2019). Recently, a behemoth TE named Teratorn was described in teleost fish; it can be up to 182 kb in length, dwarfing all other known TEs. Teratorn has achieved this impressive size by fusing a piggyBac DNA transposon with a herpesvirus, thereby blurring the line between TEs and viruses (Inoue et al. 2017, 2018). Truly massive transposons may be lurking in the depths of many eukaryotic genomes, but the limitations of short-read genome sequencing technologies and the lack of population-level high-quality assemblies may make them difficult to identify.The Spok block is a large genomic feature that was first identified thanks to the presence of the spore killing (Spok) genes in species from the genus Podospora (Grognet et al. 2014; Vogan et al. 2019). The Spoks are selfish genetic elements that bias their transmission to the next generation in a process known as meiotic drive. Here, drive occurs by inducing the death of spores that do not inherit them, through a single protein that operates as both a toxin and an antidote (Grognet et al. 2014; Vogan et al. 2019). The first Spok gene described, Spok1, was discovered in Podospora comata (Grognet et al. 2014). In P. anserina, the homologous gene Spok2 is found at high population frequencies, whereas two other genes of the Spok family, Spok3 and Spok4, are at low to intermediate frequencies (Vogan et al. 2019). Unlike Spok1 and Spok2, however, Spok3 and Spok4 are always associated with a large genomic region (the Spok block). The Spok block can be located at different chromosomal locations in different individuals but is never found more than once in natural strains. The number of Spok genes and the location of the Spok block (which carries Spok3, Spok4, or both) define the overall meiotic driver behavior of a given genome, which can be classified into the so-called Podospora spore killers or Psks (van der Gaag et al. 2000; Vogan et al. 2019). The Spok block stands out not only because of its size, typically around 150 kb, but also because there is otherwise high genome collinearity among strains of P. anserina and with the related species P. comata and P. pauciseta (Vogan et al. 2019).The fact that the Spok block is found at unique genomic positions between otherwise highly similar strains is of prime interest as each novel Spok block position creates a unique meiotic drive type (Psk) due to the intricacies of meiosis in Podospora (Vogan et al. 2019). We therefore set out to determine the mechanism through which the Spok block relocates throughout the genome. Additionally, we annotated the gene content of the various Spok blocks to describe their composition and understand what represents the minimal component of the Spok block. Lastly, we conducted fitness assays to investigate whether the presence of the Spok block imparts any detrimental effects upon the host. 相似文献