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BACKGROUND: Abdominoplasty surgery is a common body contouring surgery to remove excess fat and skin and restore weakened or separated abdominal muscles caused by aging, pregnancy, or weight fluctuations. There is limited literature regarding patient and pregnancy outcomes after abdominoplasty. OBJECTIVE: This study aimed to determine whether there was a correlation between adverse pregnancy outcomes and history of abdominoplasty. STUDY DESIGN: Our study used a large federated deidentified national health research network with data sourced from 68 healthcare organizations within the United States (TriNetX; data accessed on August 19, 2022). All patients with a record of pregnancy were identified using the International Classification of Diseases, Ninth Revision and Tenth Revision, codes and were grouped into those with a history of abdominoplasty and those without. This study evaluated the perinatal outcomes of fetal growth restriction, abnormal umbilical artery Dopplers, gestational hypertension, preeclampsia, preterm delivery, preterm premature rupture of membranes, gestational diabetes mellitus, macrosomia, stillbirth, abnormal placentation, and wound disruption or infection occurring during a patient's pregnancy after abdominoplasty. Propensity matching was performed to account for potential confounders. An alpha level of <.05 was considered statistically significant. RESULTS: Of the 44,737 patients meeting our criteria, 304 had a history of abdominoplasty, whereas 44,433 did not (control). Our study found that patients with a history of abdominoplasty had significantly higher gravidity, were largely located in the Southern and Midwest region, and had higher counts of vaginal deliveries and cesarean deliveries than the control cohort (Table 1). After propensity score matching, our study found a lower risk of preeclampsia and preterm premature rupture of membranes in patients with abdominoplasty (odds ratio, 0.46; 95% confidence interval, 0.32-0.67; P<.0001) (Table 2). Furthermore, abdominoplasty was associated with an increased risk of preterm delivery (odds ratio, 2.15; 95% confidence interval, 1.48-3.13; P=.0002) (Table 2). Lastly, this study did not find significant differences in the other perinatal outcomes (Table 2). CONCLUSION: Our data suggest that abdominoplasty may be associated with a relative increase in the rates of preterm delivery and cesarean delivery and that other perinatal outcomes are not increased. This provides evidence that future desire for pregnancy need not be a relative contraindication to abdominoplasty.
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Abdominoplastia , Resultado da Gravidez , Humanos , Gravidez , Feminino , Abdominoplastia/métodos , Abdominoplastia/efeitos adversos , Estudos Retrospectivos , Adulto , Resultado da Gravidez/epidemiologia , Complicações na Gravidez/epidemiologia , Estados Unidos/epidemiologia , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/etiologia , Recém-NascidoAssuntos
Colo , Reto , Masculino , Humanos , Colo/patologia , Biópsia , Reto/diagnóstico por imagem , Dor Abdominal/diagnóstico , Dor Abdominal/etiologia , Dor Abdominal/patologia , HiperplasiaRESUMO
BACKGROUND: Bariatric surgery is an effective treatment for obesity and may decrease the morbidity and mortality of obesity-associated cancers. OBJECTIVE: We investigated the risk of a new diagnosis of Barrett esophagus (BE) following bariatric surgery compared to screening colonoscopy controls. SETTING: Large national database including patients who received care in inpatient, outpatient, and specialty care services. METHODS: A national healthcare database (TriNetX, LLC) was used for this analysis. Cases included adults (aged ≥18 yr) who had undergone either sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB). Controls included adults undergoing screening colonoscopy and an esophagoduodenoscopy on the same day and had never undergone bariatric surgery. Cases and controls were propensity-matched for confounders. The risk of de novo diagnosis of BE at least 1 year after bariatric surgery was compared between cases and controls. Secondary analyses examined the effect of bariatric surgery on metabolic outcomes such as weight loss and body mass index (BMI). The risk of de novo diagnosis of BE in SG was compared with RYGB. Odds ratios (OR) and 95% CI were used to report on these associations. RESULTS: In the propensity-matched analysis, patients who had undergone a bariatric surgical procedure showed a significantly reduced risk of de novo BE when compared with screening colonoscopy controls (.67 [.48, .94]). There was substantial reduction in weight and BMI in the bariatric surgery group when compared with baseline. There was no significant difference in de novo BE diagnosis between the propensity-matched SG and RYGB groups (.77 [.5, 1.2]). CONCLUSION: Patients who underwent bariatric surgery (RYGB or SG) had a lower risk of being diagnosed with BE compared with screening colonoscopy controls who did not receive bariatric surgery. This effect appears to be largely mediated by reduction in weight and BMI.
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Cirurgia Bariátrica , Esôfago de Barrett , Derivação Gástrica , Obesidade Mórbida , Adulto , Humanos , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Esôfago de Barrett/diagnóstico , Esôfago de Barrett/epidemiologia , Esôfago de Barrett/etiologia , Cirurgia Bariátrica/efeitos adversos , Cirurgia Bariátrica/métodos , Derivação Gástrica/métodos , Resultado do Tratamento , Obesidade/cirurgia , Gastrectomia/efeitos adversos , Gastrectomia/métodos , Estudos RetrospectivosRESUMO
BACKGROUND & AIMS: Guidelines suggest a single screening esophagogastroduodenoscopy (EGD) in patients with multiple risk factors for Barrett's esophagus (BE). We aimed to determine BE prevalence and predictors on repeat EGD after a negative initial EGD, using 2 large national databases (GI Quality Improvement Consortium [GIQuIC] and TriNetX). METHODS: Patients who underwent at least 2 EGDs were included and those with BE or esophageal adenocarcinoma detected at initial EGD were excluded. Patient demographics and prevalence of BE on repeat EGD were collected. Multivariate logistic regression was performed to assess for independent risk factors for BE detected on the repeat EGD. RESULTS: In 214,318 and 153,445 patients undergoing at least 2 EGDs over a median follow-up of 28-35 months, the prevalence of BE on repeat EGD was 1.7% in GIQuIC and 3.4% in TriNetX, respectively (26%-45% of baseline BE prevalence). Most (89%) patients had nondysplastic BE. The prevalence of BE remained stable over time (from 1 to >5 years from negative initial EGD) but increased with increasing number of risk factors. BE prevalence in a high-risk population (gastroesophageal reflux disease plus ≥1 risk factor for BE) was 3%-4%. CONCLUSIONS: In this study of >350,000 patients, rates of BE on repeat EGD ranged from 1.7%-3.4%, and were higher in those with multiple risk factors. Most were likely missed at initial evaluation, underscoring the importance of a high-quality initial endoscopic examination. Although routine repeat endoscopic BE screening after a negative initial examination is not recommended, repeat screening may be considered in carefully selected patients with gastroesophageal reflux disease and ≥2 risk factors for BE, potentially using nonendoscopic tools.
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Esôfago de Barrett , Neoplasias Esofágicas , Refluxo Gastroesofágico , Humanos , Esôfago de Barrett/diagnóstico , Esôfago de Barrett/epidemiologia , Esôfago de Barrett/patologia , Prevalência , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/epidemiologia , Endoscopia Gastrointestinal , Refluxo Gastroesofágico/epidemiologia , Endoscopia do Sistema DigestórioRESUMO
Assessing the environmental factors that influence the ability of a threatened species to move through a landscape can be used to identify conservation actions that connect isolated populations. However, direct observations of species' movement are often limited, making the development of alternate approaches necessary. Here we use landscape genetic analyses to assess the impact of landscape features on the movement of individuals between local populations of a threatened snake, the eastern massasauga rattlesnake (Sistrurus catenatus). We linked connectivity data with habitat information from two landscapes of similar size: a large region of unfragmented habitat and a previously studied fragmented landscape consisting of isolated patches of habitat. We used this analysis to identify features of the landscape where modification or acquisition would enhance population connectivity in the fragmented region. We found evidence that current connectivity was impacted by both contemporary land-cover features, especially roads, and inherent landscape features such as elevation. Next, we derived estimates of expected movement ability using a recently developed pedigree-based approach and least-cost paths through the unfragmented landscape. We then used our pedigree and resistance map to estimate resistance polygons of the potential extent for S. catenatus movement in the fragmented landscape. These polygons identify possible sites for future corridors connecting currently isolated populations in this landscape by linking the impact of future habitat modification or land acquisition to dispersal ability in this species. Overall, our study shows how modeling landscape resistance across differently fragmented landscapes can identify habitat features that affect contemporary movement in threatened species in fragmented landscapes and how this information can be used to guide mitigation actions whose goal is to connect isolated populations.
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Crotalus , Espécies em Perigo de Extinção , Humanos , Animais , Crotalus/genética , EcossistemaRESUMO
Managing endangered species in fragmented landscapes requires estimating dispersal rates between populations over contemporary timescales. Here, we developed a new method for quantifying recent dispersal using genetic pedigree data for close and distant kin. Specifically, we describe an approach that infers missing shared ancestors between pairs of kin in habitat patches across a fragmented landscape. We then applied a stepping-stone model to assign unsampled individuals in the pedigree to probable locations based on minimizing the number of movements required to produce the observed locations in sampled kin pairs. Finally, we used all pairs of reconstructed parent-offspring sets to estimate dispersal rates between habitat patches under a Bayesian model. Our approach measures connectivity over the timescale represented by the small number of generations contained within the pedigree and so is appropriate for estimating the impacts of recent habitat changes due to human activity. We used our method to estimate recent movement between newly discovered populations of threatened Eastern Massasauga rattlesnakes (Sistrurus catenatus) using data from 2996 RAD-based genetic loci. Our pedigree analyses found no evidence for contemporary connectivity between five genetic groups, but, as validation of our approach, showed high dispersal rates between sample sites within a single genetic cluster. We conclude that these five genetic clusters of Eastern Massasauga rattlesnakes have small numbers of resident snakes and are demographically isolated conservation units. More broadly, our methodology can be widely applied to determine contemporary connectivity rates, independent of bias from shared genetic similarity due to ancestry that impacts other approaches.
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Crotalus , Genética Populacional , Animais , Teorema de Bayes , Crotalus/genética , Ecossistema , Espécies em Perigo de Extinção , América do Norte , LinhagemRESUMO
Endangered species that exist in small isolated populations are at elevated risk of losing adaptive variation due to genetic drift. Analyses that estimate short-term effective population sizes, characterize historical demographic processes, and project the trajectory of genetic variation into the future are useful for predicting how levels of genetic diversity may change. Here, we use data from two independent types of genetic markers (single nucleotide polymorphisms [SNPs] and microsatellites) to evaluate genetic diversity in 17 populations spanning the geographic range of the endangered eastern massasauga rattlesnake (Sistrurus catenatus). First, we use SNP data to confirm previous reports that these populations exhibit high levels of genetic structure (overall Fst = 0.25). Second, we show that most populations have contemporary Ne estimates <50. Heterozygosity-fitness correlations in these populations provided no evidence for a genetic cost to living in small populations, though these tests may lack power. Third, model-based demographic analyses of individual populations indicate that all have experienced declines, with the onset of many of these declines occurring over timescales consistent with anthropogenic impacts (<200 years). Finally, forward simulations of the expected loss of variation in relatively large (Ne = 50) and small (Ne = 10) populations indicate they will lose a substantial amount of their current standing neutral variation (63% and 99%, respectively) over the next 100 years. Our results argue that drift has a significant and increasing impact on levels of genetic variation in isolated populations of this snake, and efforts to assess and mitigate associated impacts on adaptive variation should be components of the management of this endangered reptile.
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BACKGROUND: Ehrlichiosis is a clinically important, emerging zoonosis. Only Ehrlichia chaffeensis and E. ewingii have been thought to cause ehrlichiosis in humans in the United States. Patients with suspected ehrlichiosis routinely undergo testing to ensure proper diagnosis and to ascertain the cause. METHODS: We used molecular methods, culturing, and serologic testing to diagnose and ascertain the cause of cases of ehrlichiosis. RESULTS: On testing, four cases of ehrlichiosis in Minnesota or Wisconsin were found not to be from E. chaffeensis or E. ewingii and instead to be caused by a newly discovered ehrlichia species. All patients had fever, malaise, headache, and lymphopenia; three had thrombocytopenia; and two had elevated liver-enzyme levels. All recovered after receiving doxycycline treatment. At least 17 of 697 Ixodes scapularis ticks collected in Minnesota or Wisconsin were positive for the same ehrlichia species on polymerase-chain-reaction testing. Genetic analyses revealed that this new ehrlichia species is closely related to E. muris. CONCLUSIONS: We report a new ehrlichia species in Minnesota and Wisconsin and provide supportive clinical, epidemiologic, culture, DNA-sequence, and vector data. Physicians need to be aware of this newly discovered close relative of E. muris to ensure appropriate testing, treatment, and regional surveillance. (Funded by the National Institutes of Health and the Centers for Disease Control and Prevention.).
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Ehrlichia/classificação , Ehrlichiose/microbiologia , Ixodes/microbiologia , Zoonoses/microbiologia , Animais , Ehrlichia/genética , Ehrlichia/isolamento & purificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Minnesota , Filogenia , Reação em Cadeia da Polimerase , Wisconsin , Adulto JovemRESUMO
Treatment of a maxillary central incisor with an associated cystic lesion by conventional endodontic therapy combined with decompression is reported. Although small cystic lesions frequently heal simply with endodontic therapy, larger lesions may need additional treatment. If surgical enucleation is elected, other teeth or structures may be damaged unnecessarily. Therefore, a case can be made for first attempting the more conservative treatment of decompression, and a workable protocol for this is presented. In this case, 6 weeks with latex tubing in place and daily irrigation with 0.12% chlorhexidine led to complete healing with no need for further surgery or other root canal therapy on teeth initially surrounded by this lesion. At the 2-year recall, the lesion has completely resolved, and the adjacent teeth remain vital and normal.
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Cisto Radicular/terapia , Adolescente , Anti-Infecciosos Locais/uso terapêutico , Clorexidina/uso terapêutico , Descompressão Cirúrgica , Fístula Dentária/etiologia , Fístula Dentária/terapia , Humanos , Incisivo , Masculino , Maxila , Cisto Radicular/complicações , Tratamento do Canal RadicularRESUMO
CONTEXT: The PathFocus program affords the opportunity for participating pathology practices to be compared with other practices that have similar characteristics. OBJECTIVES: To demonstrate variability in workload among different pathology practice settings and to determine practice characteristics that influence staffing levels. DESIGN: Among 228 group practices in the PathFocus database, group practice settings were analyzed. The practice characteristics that were highly correlated with staffing levels are presented. RESULTS: Activities that showed significant variation include surgical pathology (P = .003), cytopathology (P = .006), miscellaneous (P = .006), and professional development (P = .003). Group practices report up to 4% of hours devoted to clinical pathology consultation, on average, and from 20% to 25% to administration and management. There are strong positive associations with staffing levels for lower-complexity Current Procedural Terminology code volumes (P < .001) and higher-complexity Current Procedural Terminology code volumes (P = .006). CONCLUSION: The settings of pathology practices carry specific commitments of time that are different and not equally distributed among all practice settings and strongly influence staffing requirements.
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Pessoal Técnico de Saúde , Patologia , Sociedades Médicas , Humanos , Admissão e Escalonamento de Pessoal , Estados UnidosRESUMO
The O-acetylhomoserine sulfhydrylase (OAHS) gene was cloned from a Selenomonas ruminantium HD4 Lambda ZAP II genomic library by degenerative probe hybridization and complementation. Sequence analysis revealed an 869-bp ORF with a G + C content of 53%. The ORF had significant homology with enzymes involved in homocysteine biosynthesis. A CuraBLASTN homology search showed that the ORF has 63% nucleotide identity with the OAHS of Bacillus stearothermophilus, Corynebacterium glutamicum, and Acremonium chrysogenum, and has 58% identity with met25 of Saccharomyces cerevisiae and metZ of Pseudomonas aeruginosa. The deduced amino acid sequence exhibited 45% similarity with Met25 and MetZ. Further analysis predicted that the gene product was a member of the pyridoxal phosphate enzyme family. Complementation experiments with Escherichia coli metA, metB, and metC mutant strains showed that the S. ruminantium OAHS gene can complement the metC mutation and allow for growth on minimal media that contained sodium thiosulfate as the sole source of sulfur. When the OAHS was disturbed by inserting a EZ::TN pMOD-2
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Carbono-Oxigênio Liases/genética , Rúmen/microbiologia , Selenomonas/enzimologia , Animais , Sequência de Bases , Carbono-Oxigênio Liases/química , Clonagem Molecular , Escherichia coli/genética , Metionina/metabolismo , Dados de Sequência Molecular , Selenomonas/genéticaRESUMO
The objective of this study was to evaluate the effects of 0, 4, 8, and 12 mM DL-malate on the in vitro mixed ruminal microorganism fermentation of alfalfa hay and Coastal bermudagrass hay. When alfalfa hay was the substrate, 4 and 8 mM DL-malate numerically increased propionate concentration, and 12 mM DL-malate increased (P < 0.10) propionate. All three concentrations of DL-malate decreased (P < 0.05) the acetate:propionate ratio. In Coastal bermudagrass hay fermentations, all three DL-malate concentrations increased (P < 0.05) propionate and decreased (P < 0.05) the acetate:propionate ratio, while 4 and 12 mM DL-malate numerically increased in vitro dry matter disappearance. When mixed ruminal microorganisms were incubated with 6.25 mM DL-lactic acid and alfalfa hay, 8 and 12 mM DL-malate increased (P < 0.05) final pH, and 12 mM DL-malate increased (P < 0.10) propionate and decreased (P < 0.10) the acetate:propionate ratio. DL-Malate treatment had little effect on in vitro dry matter disappearance. Addition of 8 and 12 mM DL-malate to Coastal bermudagrass hay plus DL-lactic acid fermentations increased (P < 0.05) final pH, and 8 mM DL-malate increased (P < 0.10) in vitro dry matter disappearance. Even though DL-malate treatment consistently increased final pH values in fermentations that included DL-lactic acid, there was not a corresponding increase in in vitro dry matter disappearance of either alfalfa hay or Coastal bermudagrass hay in the 48-h batch culture incubations.
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Bovinos/metabolismo , Fibras na Dieta/metabolismo , Malatos/farmacologia , Rúmen/metabolismo , Selenomonas/metabolismo , Animais , Bovinos/microbiologia , Cynodon/metabolismo , Ácidos Graxos Voláteis/metabolismo , Fermentação , Hidrogênio/metabolismo , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Ácido Láctico/metabolismo , Ácido Láctico/farmacologia , Malatos/metabolismo , Masculino , Medicago sativa/metabolismo , Metano/metabolismo , Rúmen/efeitos dos fármacos , Rúmen/microbiologia , Selenomonas/efeitos dos fármacosRESUMO
Microarray analysis is an emerging technology that has the potential to become a leading trend in bacterial identification in food and feed improvement. The technology uses fluorescent-labeled probes amplified from bacterial samples that are then hybridized to thousands of DNA sequences immobilized on chemically modified glass slides. The whole gene or open reading frame(s) is represented by a polymerase chain reaction fragment of double-strand DNA, approximately 1000 base pair (bp) or 20-70 bp single-strand oligonucleotides. The technology can be used to identity bacteria and to study gene expression in complex microbial populations, such as those found in food and gastrointestinal tracts. Data generated by microarray analysis can be potentially used to improve the safety of our food supply as well as ensure the efficiency of animal feed conversion to human food, e.g., in meat and milk production by ruminants. This minireview addresses the use of microarray technology in bacterial identification and gene expression in different microbial systems and in habitats containing mixed populations of bacteria.
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Microbiologia de Alimentos , Análise de Sequência com Séries de Oligonucleotídeos , Animais , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/patogenicidade , Técnicas Bacteriológicas , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Meio Ambiente , Genes Bacterianos , Humanos , Rúmen/microbiologiaRESUMO
The gene coding for O-acetylserine lyase (OASL) was cloned from a Selenomonas ruminantium HD4 Lambda ZAP II genomic library by degenerative probe hybridization and complementation. Sequence analysis revealed a 933 bp ORF with a G + C content of 53%. The ORF had significant homology with enzymes involved in cysteine biosynthesis. A CuraBLASTN homology search showed that the ORF shared 59% nucleotide identity with the cysK of Bacillus subtilis. The deduced amino acid sequence exhibited high (>70%) similarity with the CysK of B. subtilis and other cysteine synthesis proteins from Mycobacterium tuberculosis, Mycobacterium leprae, and Spinacia oleracea. Further analysis predicted that the gene product was a member of the pyridoxal phosphate enzyme family and of cytoplasmic origin. Phylogenetic analysis clustered the S. ruminantium gene product with the OASLa isoform of B. subtilis and the OASLb isoforms of Streptococcus suis, Escherichia coli, and Campylobacter jejuni. The OASL of S. ruminantium HD4 was also able to complement the cysM cysK double mutations in Escherichia coli NK3 and allow for growth on minimal media that contained either sulfate or thiosulfate as the sole source of sulfur. These results suggest that the gene functions as a cysM in S. ruminantium HD4. In conclusion, this research describes the cloning and expression of an O-acetylserine lyase gene from the predominant ruminal anaerobe S. ruminantium HD4. To our knowledge, this is the first report characterizing genes involved in sulfur metabolism from the genus Selenomonas.
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Cisteína Sintase/genética , Genes Bacterianos , Selenomonas/enzimologia , Selenomonas/genética , Sequência de Aminoácidos , Animais , Bacillus subtilis/enzimologia , Bacillus subtilis/genética , Sequência de Bases , Clonagem Molecular , DNA Bacteriano/genética , Escherichia coli/genética , Expressão Gênica , Teste de Complementação Genética , Dados de Sequência Molecular , Filogenia , Rúmen/microbiologia , Homologia de Sequência de AminoácidosRESUMO
A clone from a Selenomonas ruminantium HD4 Lambda ZAP II genomic library was isolated by its ability to complement the anaerobic growth deficiency of an Escherichia coli (pfl, ldh) double mutant. The 1.0-kb insert from the clone was sequenced and revealed a single open reading frame (ORF, 957-bp) which was preceded by a putative Shine-Dalgarno (SD) sequence (AGGGGG). The potential SD sequence corresponded to 3' 16S rRNA sequences of various Selenomonas strains. The ORF was predicted to encode a protein of 318 amino acids with a calculated molecular mass of 34,975 Da and an isoelectric point of 5.54. In addition, the ORF contained 51 mol % G + C and this is consistent with the average G + C content (54%) of the S. ruminantium chromosome. The cloned S. ruminantium gene exhibited 59% nucleotide identity and 61% deduced amino acid similarity with L-lactate dehydrogenases (L-LDH) of Pediococcus acidilactici and Bacillus megaterium, respectively. Incorporation of the cloned S. ruminantium gene into E. coli DC1368 (pfl, ldh) restored anaerobic growth on glucose and L-LDH activity was detected in cell extracts. Because lactate accumulation within the rumen can be detrimental to animal performance, characterizing the gene(s) involved in lactate production by predominant ruminal bacteria will lead to a better understanding of lactate metabolism within the rumen.
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Genes Bacterianos , L-Lactato Desidrogenase/genética , Selenomonas/enzimologia , Selenomonas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Bacteriano/genética , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Expressão Gênica , Teste de Complementação Genética , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia , Rúmen/microbiologiaRESUMO
We report the clinicopathologic, immunohistochemical, and DNA ploidy findings of 18 leiomyosarcomas of the urinary bladder. In addition, we compare these malignant smooth muscle tumors with 10 cases of urinary bladder leiomyoma. The 14 male and four female patients with leiomyosarcoma ranged in age from 25 to 88 years (mean 64 years). The tumors ranged from 3.0 to 15.0 cm (mean 7.1 cm) in greatest dimension and were moderately to highly cellular, consisting of interlacing fascicles of spindled cells with mild to marked nuclear atypia. Coagulative tumor necrosis was identified in 14 cases (78%), and mitotic activity ranged from 1 to 42 mitotic figures (MF) per 10 high power fields (HPF) (mean 12 MF/10 HPF). Tumors were classified as either high-grade (12 cases) or low-grade (six cases) based on nuclear atypia, mitotic activity, and tumor necrosis. Actin positivity was present in 15 tumors (83%), and desmin immunoreactivity was present in seven tumors (39%). All cases were negative for epithelial markers and S-100. Proliferative activity, as assessed by MIB-1 staining, ranged from 0.1% to 51.4% (median 9.1%). Seven (39%) of the leiomyosarcomas were DNA aneuploid, eight (44%) were tetraploid, and three (17%) were diploid. Five patients underwent radical cystoprostatectomy, one radical cystectomy, seven had partial cystectomy, two underwent pelvic exenteration, and three patients had transurethral resection only. Follow-up information was available on all 18 cases and ranged from 2 to 68 months (mean 22 months). Of the 12 patients with high-grade tumors, six (50%) died of disease from 2 to 20 months (mean 7 months) after diagnosis and three patients (25%) are alive with metastatic tumor. Two of the six patients with low-grade leiomyosarcoma died of tumor, 61 and 68 months after diagnosis. There were five male and five female patients with leiomyoma ranging in age from 22 to 78 years (mean 61 years). The tumors ranged from 0.5 to 4.5 cm (mean 1.6 cm) in greatest dimension, were well circumscribed, and had low cellularity. Mitotic activity, necrosis, and cellular atypia were absent, and the tumors were strongly positive for both actin and desmin. MIB-1 staining ranged from 0% to 3.8% (median 0.8%). Seven (87.5%) of the leiomyomas were DNA diploid or near-diploid and one (12.5%) was DNA aneuploid. Six patients were treated with transurethral resection and four with partial cystectomy. All 10 patients were alive at the last follow-up (mean follow-up 75 months), and no tumor recurred or metastasized. Our study shows that low-grade leiomyosarcomas are capable of malignant behavior, and high-grade leiomyosarcomas appear to behave more aggressively than low-grade tumors. In addition, the diagnosis of urinary bladder leiomyoma should be reserved for noninfiltrative smooth muscle tumors lacking mitotic activity, cytologic atypia, and necrosis.