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The current article is a summary of the 2018 revised S3 guideline on screening, diagnosis, therapy, and follow-up of the abdominal aortic aneurysm (AAA) from an anesthesiological point of view. It is the only interdisciplinary guideline that describes in particular the perioperative anesthesiological and intensive care management.
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Anestesia/normas , Aneurisma da Aorta Abdominal/cirurgia , Anestesiologia , Aneurisma da Aorta Abdominal/diagnóstico , Cuidados Críticos/normas , Guias como Assunto , Humanos , Assistência Perioperatória/normas , Procedimentos Cirúrgicos Vasculares/normasRESUMO
In Egypt, hepatocellular carcinoma (HCC) is the most common form of cancer and direct-acting antivirals (DAA) are administered on a large scale to patients with chronic HCV infection to reduce the risk. In this unique setting, we aimed to determine the association of DAA exposure with early-phase HCC recurrence in patients with a history of HCV-related liver cancer. This was a prospective cohort study of an HCV-infected population from one Egyptian specialized HCC management centre starting from the time of successful HCC intervention. The incidence rates of HCC recurrence between DAA-exposed and nonexposed patients were compared, starting from date of HCC complete radiological response and censoring after 2 years. DAA exposure was treated as time varying. Two Poisson regressions models were used to control for potential differences in the exposed and nonexposed group; multivariable adjustment and balancing using inverse probability of treatment weighting (IPTW). We included 116 patients: 53 treated with DAAs and 63 not treated with DAAs. There was 37.7% and 25.4% recurrence in each group after a median of 16.0 and 23.0 months of follow-up, respectively. Poisson regression using IPTW demonstrated an association between DAAs and HCC recurrence with an incidence rate ratio of 3.83 (95% CI: 2.02-7.25), which was similar in the multivariable-adjusted model and various sensitivity analyses. These results add important evidence towards the possible role of DAAs in HCC recurrence and stress the need for further mechanistic studies and clinical trials to accurately confirm this role and to identify patient characteristics that may be associated with this event.
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Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/cirurgia , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/cirurgia , Egito/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , RecidivaRESUMO
Langerhans cell histiocytosis is a disease with different clinical presentations and a wide spectrum of organ involvements. Rarely Langerhans cell histiocytosis can involve the gastrointestinal tract of adult patients. A case of infiltration of gastric mucosa by Langerhans cell histiocytosis is presented. The neoplastic nature of this infiltrate is underlined by the detection of a BRAF-V600E-mutation. Additionally, an overview of the so far 5 cases published in the English literature is provided. The published clinical experience indicates a benign curse of the disease.
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Histiocitose de Células de Langerhans/diagnóstico , Histiocitose de Células de Langerhans/genética , Polimorfismo de Nucleotídeo Único/genética , Proteínas Proto-Oncogênicas B-raf/genética , Gastropatias/diagnóstico , Gastropatias/genética , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Mutação/genéticaRESUMO
The insula is an integral component of sensory, motor, limbic, and executive functions, and insular dysfunction is associated with numerous human neuropsychiatric disorders. Insular afferents project widely, but insulo-striate projections are especially numerous. The targets of these insulo-striate projections are organized into tissue compartments, the striosome and matrix. These striatal compartments have distinct embryologic origins, afferent and efferent connectivity, dopamine pharmacology, and susceptibility to injury. Striosome and matrix appear to occupy separate sets of cortico-striato-thalamo-cortical loops, so a bias in insulo-striate projections towards one compartment may also embed an insular subregion in distinct regulatory and functional networks. Compartment-specific mapping of insulo-striate structural connectivity is sparse; the insular subregions are largely unmapped for compartment-specific projections. In 100 healthy adults, we utilized probabilistic diffusion tractography to map and quantify structural connectivity between 19 structurally-defined insular subregions and each striatal compartment. Insulo-striate streamlines that reached striosome-like and matrix-like voxels were concentrated in distinct insular zones (striosome: rostro- and caudoventral; matrix: caudodorsal) and followed different paths to reach the striatum. Though tractography was generated independently in each hemisphere, the spatial distribution and relative bias of striosome-like and matrix-like streamlines were highly similar in the left and right insula. 16 insular subregions were significantly biased towards one compartment: seven toward striosome-like voxels and nine toward matrix-like voxels. Striosome-favoring bundles had significantly higher streamline density, especially from rostroventral insular subregions. The biases in insulo-striate structural connectivity we identified mirrored the compartment-specific biases identified in prior studies that utilized injected tract tracers, cytoarchitecture, or functional MRI. Segregating insulo-striate structural connectivity through either striosome or matrix may be an anatomic substrate for functional specialization among the insular subregions.
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Benzodiazepines, often used to treat anxiety, insomnia, and other conditions, are prescribed more frequently to women than men, and emergency department visits and overdose deaths involving benzodiazepines have increased significantly among women in recent years. This study describes characteristics and trends associated with benzodiazepine exposures among women of reproductive age (15-49 years old) that were reported to United States poison control centers from 2004 through 2018. The National Poison Data System recorded 258,370 first-ranked benzodiazepine exposures among women 15-49 years old during the study period. More than one-half (56.9%) of exposures involved a single-substance and one-third (34.0%) occurred among women 20-29 years old. The majority were categorized as "intentional, suspected suicide" (73.2%) or "intentional" (12.9%). Exposures frequently resulted in admission to a psychiatric facility (20.6%), critical care unit (18.1%), or non-critical care unit (9.3%). Twenty percent of cases resulted in a serious medical outcome, including 205 deaths. The substantial percentage of benzodiazepine exposures among women of reproductive age that were intentional and associated with suicide attempts or suicide deaths indicate that increased prevention efforts are needed to address this issue.
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Benzodiazepinas/toxicidade , Benzodiazepinas/uso terapêutico , Centros de Controle de Intoxicações/estatística & dados numéricos , Centros de Controle de Intoxicações/tendências , Uso Excessivo de Medicamentos Prescritos/estatística & dados numéricos , Uso Excessivo de Medicamentos Prescritos/tendências , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Adulto JovemRESUMO
Detailed electronic many-body configurations are extracted from quantitatively measured time-resolved nonlinear absorption spectra of resonantly excited GaAs quantum wells. The microscopic theory assigns the observed spectral changes to a unique mixture of electron-hole plasma, exciton, and polarization effects. Strong transient gain is observed only under cocircular pump-probe conditions and is attributed to the transfer of pump-induced coherences to the probe.
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Isolated cobalt-alcohol cluster anions containing n=1-4 cobalt and m=1-3 alcohol molecules (alcohol=methanol, ethanol, propanol) are produced in a supersonic beam by using a laser ablation source. By applying IR photodissociation spectroscopy vibrational spectra in the OH stretching region are obtained. Several structures in different spin states are discussed for the (n,m) clusters. In comparison with density functional theory calculations applied to both the Co/alcohol clusters and the naked Co cluster anions, an unambiguous structural assignment is achieved. It turns out that structures are preferred with a maximum number of hydrogen bonds between the OH groups and the Co···Co units. These hydrogen bonds are typical for anionic species leading to an activation of the OH groups which is indicated by large red-shifts of the OH stretching frequencies compared to the naked alcohols. For each (n,m) cluster, the frequency shifts systematically with respect to the different alcohols, but the type of structure is identical for all alcohol ligands. The application of IR spectroscopy turns out to be an ideal tool not only as a probe for structures but also for spin states which significantly influence the predicted OH stretching frequencies.
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The structure and reactivity of isolated 3-hydroxyflavone (3-HF) aggregates with one and two water molecules has been investigated by applying combined infrared/ultraviolet (IR/UV) spectroscopy in a supersonic jet both for the electronic ground and excited states. In combination with density functional theory (DFT) calculations, the IR spectra of the S(0) states recorded from the upper fingerprint region to the OH stretching vibrations are assigned to the most stable isomers of the clusters. For the first electronically excited (pi pi(*)) state of the 3-HF(H(2)O)(2) cluster structural information are obtained from the IR spectra in combination with time-dependent-DFT (TD-DFT) calculations. No proton transfer structure is observed in the case of a low excess energy within the electronically excited state. By raising the excitation energy, additional bands appear that can be assigned to a tautomeric form indicating the induction of a proton transfer reaction.
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Elétrons , Flavonoides/química , Prótons , Água/química , Teoria Quântica , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , TemperaturaRESUMO
The differential expression of the critical cell cycle control proteins cyclin D1 and c-myc has been shown to result in Akt-dependent hypersensitivity of tumor cells to mTOR inhibitors. We have previously demonstrated that the differential utilization of internal ribosome entry sites within the mRNAs of these transcripts allows maintenance of protein synthesis in the face of rapamycin (rapa) exposure in an Akt-dependent manner. Here, we demonstrate that in addition to this mechanism, cyclin D1 and c-myc mRNA stability is also coordinately regulated following rapa treatment depending on Akt activity status. We identify A/U-rich response elements within the 3' untranslated regions (UTRs) of these transcripts, which confer the observed differential stabilities and show that the RNA-binding protein, tristetraprolin (TTP), interacts with these elements. We also present evidence that TTP accumulates in response to rapa exposure, binds to the cis-acting elements within the cyclin D1 and c-myc 3' UTRs and is differentially serine phosphorylated in an Akt-dependent manner. Furthermore, the differential phosphorylation status of TTP results in its sequestration by 14-3-3 proteins in quiescent Akt-containing cells. Finally, siRNA-mediated knockdown of TTP expression or inhibiting a known regulator of TTP phosphorylation, p38 MAP kinase, abolishes the effects on cyclin D1 and c-myc mRNA stability. We assume that the differential control of cyclin D1 and c-myc mRNA stability and translational efficiency constitutes a coordinate response to rapa contributing to the maintenance of expression of these determinants in rapa-resistant quiescent Akt-containing cells following exposure.
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Fibroblastos/efeitos dos fármacos , Genes bcl-1 , Genes myc , Proteínas Proto-Oncogênicas c-akt/fisiologia , RNA Mensageiro/metabolismo , Sirolimo/farmacologia , Tristetraprolina/fisiologia , Proteínas Quinases p38 Ativadas por Mitógeno/fisiologia , Proteínas 14-3-3/metabolismo , Animais , Linhagem Celular/efeitos dos fármacos , Linhagem Celular/metabolismo , Ciclina D , Ciclinas/genética , Dactinomicina/farmacologia , Embrião de Mamíferos , Fibroblastos/metabolismo , Genes Reporter , Meia-Vida , Imidazóis/farmacologia , Camundongos , PTEN Fosfo-Hidrolase/deficiência , PTEN Fosfo-Hidrolase/fisiologia , Fosforilação , Fosfosserina/metabolismo , Ligação Proteica/efeitos dos fármacos , Processamento de Proteína Pós-Traducional , Inibidores da Síntese de Proteínas/farmacologia , Piridinas/farmacologia , Interferência de RNA , RNA Interferente Pequeno/farmacologia , Proteínas Recombinantes de Fusão/metabolismo , Sequências Reguladoras de Ácido Nucleico , Ribossomos/metabolismo , Tristetraprolina/química , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidoresRESUMO
BACKGROUND: Approximately half of the patients diagnosed with localized esophageal cancer die of metastatic disease within the first 2 years following tumor resection. The development of monoclonal antibodies (MAbs) directed against epithelial cell-associated and tumor antigens has enabled the detection of single disseminated tumor cells in secondary organs. PURPOSE: We used MAbs directed against epithelial cell antigens (i.e., cytokeratins) to determine the proportion of patients with esophageal cancer who display isolated tumor cells in their bone marrow. In addition, we evaluated the prognostic significance of a finding of bone marrow tumor cells in patients with esophageal cancer whose tumors were completely resected. METHODS: Prior to the initiation of treatment, bone marrow was aspirated from both sides of the upper iliac crests of 90 patients with squamous cell carcinoma of the esophagus. Bone marrow was also obtained from a population of 30 individuals who had not been diagnosed with cancer. Tumor cells in cytologic bone marrow preparations were detected by use of an assay that employed the MAbs CK2 (directed against cytokeratin 18), KL1 (directed against a 56,000-kd pan-cytokeratin component), and A45-B/B3 (directed against an epitope common to cytokeratins 8, 18, and 19) plus the alkaline phosphatase anti-alkaline phosphatasestaining method. Bone marrow biopsies, for conventional histologic examination with Giemsa staining, were performed on 62 patients. The Kaplan-Meier method and the logrank test were used to assess disease-free and overall survival according to the presence or absence of tumor cells in the bone marrow of 42 patients with completely resected tumors. Reported P values are two-sided. RESULTS: Cytokeratin-positive tumor cells were detected in the bone marrow of 37 (41.1%) of the 90 total patients. The number of tumor cells detected per 10(5) mononuclear bone marrow cells ranged from one to 82. No significant differences in the numbers of disseminated tumor cells were noted for patients diagnosed with tumors at different stages. Only two (3.2%) of 62 bone marrow specimens examined after Giemsa staining showed morphologically identifiable tumor cells. Tumor cells were not detected in the bone marrow of patients who had not been diagnosed with cancer. After a median follow-up of 15.5 months (range, 6-33 months), 15 (79.0%) of 19 patients with completely resected tumors and tumor cells in their bone marrow had relapses compared with three (13.0%) of 23 patients with completely resected tumors and no tumor cells in their bone marrow (P = .019, logrank test). Patients with completely resected tumors and tumor cells in their bone marrow had significantly shorter overall survival than corresponding patients without tumor cells in their bone marrow (P = .036, logrank test). CONCLUSIONS AND IMPLICATIONS: Dissemination of esophageal cancer cells to the bone marrow is more frequent than expected from the rare occurrence of overt skeletal metastases. In general, the presence of tumor cells in the bone marrow may be an indicator of the disseminatory potential of individual tumors.
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Neoplasias da Medula Óssea/secundário , Carcinoma de Células Escamosas/secundário , Neoplasias Esofágicas/patologia , Imuno-Histoquímica , Anticorpos Monoclonais , Corantes Azur , Feminino , Humanos , Imuno-Histoquímica/métodos , Queratinas/imunologia , Masculino , Pessoa de Meia-Idade , Análise de SobrevidaRESUMO
BACKGROUND: The risk of mother-to-child transmission of hepatitis B virus (HBV) has been quoted as 70-90% among women positive for hepatitis B surface antigen (HBsAg) and e antigen (HBeAg), and 5-30% among HBsAg-positive HBeAg-negative women. These risks are derived from Asia; little is known about sub-Saharan Africa. AIM: To determine the risk of mother-to-child transmission in sub-Saharan Africa, according to maternal HBeAg and type of prophylaxis. METHODS: We searched Medline, Global Health, Embase, African Journals Online and African Index Medicus. We included observational or interventional studies that enrolled infants of HBV-infected women, and that tested for HBsAg or HBV DNA between 3 and 12 months of age. RESULTS: Fifteen articles from 11 African countries were included. Among HBeAg-positive women, the pooled risk was 38.3% (95% CI: 7.0-74.4%) without prophylaxis, which was significantly lower than the lower bound of 70-90% risk in the literature (P = 0.007). Among HBeAg-negative women, the pooled risk was 4.8% (95% CI: 0.1-13.3%) without prophylaxis, which lays within the lower range of the 5-30% risk in Asia. By extrapolating the pooled transmission risks to the number of births to infectious mothers, an estimated 1% of newborns (n = 367 250) are annually infected with HBV at birth in sub-Saharan Africa. CONCLUSIONS: Compared to Asia, the risk of mother-to-child transmission is low in sub-Saharan Africa. However, the annual number of infants perinatally infected with HBV is twice the number of incident paediatric HIV infections in sub-Saharan Africa (n = 190 000). This highlights the importance of preventing mother-to-child transmission of HBV in sub-Saharan Africa, which has been long neglected.
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Hepatite B/transmissão , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez , África Subsaariana , Feminino , Hepatite B/sangue , Hepatite B/virologia , Humanos , Mães , Gravidez , RiscoRESUMO
In crucial cases the diagnosis of non-Hodgkin's lymphoma (NHL) still represents a challenge to the pathologist since morphological criteria do not always help to distinguish between reactive and malignant lymphoproliferations. Clonality assays are a useful supplement since monoclonal cell proliferation is strong evidence for malignancy. The polymerase chain reaction (PCR) can be utilized to establish the clonal origin of B- or T-cell lymphocyte populations by amplification of rearranged immunoglobulin and T-cell receptor (TCR) genes. In the present study DNA was isolated from a variety of neoplastic and nonneoplastic formalin-fixed, paraffin-embedded lymph nodes (n = 62), cutaneous tissue (n = 9), samples of miscellaneous origin (n = 11), and reported here for the first time, decalcified bone marrow samples (n = 35). These samples were submitted to PCR-based assays directed against the immunoglobulin heavy-chain (IgH), immunoglobulin kappa light-chain (IgL kappa), and TCR gamma chain genes. The impact of various decalcifying agents on the ability to amplify DNA was investigated by PCR-based amplification of a single copy gene. Buffered and nonbuffered EDTA was found not to impede amplification of DNA fragments up to 300 bp in length. In lymph node and cutaneous specimens monoclonality was detected in 83% of B-NHL cases using a seminested PCR approach for the amplification of IgH, whereas the same approach gave rise to monoclonal bands in 80% of bone marrow samples. The subsequent amplification of IgL kappa helped to raise the sensitivity of detection to 94%. Monoclonality was detected in seven of nine T-cell NHLs by amplification of TCR gamma.(ABSTRACT TRUNCATED AT 250 WORDS)
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Linfoma não Hodgkin/diagnóstico , Reação em Cadeia da Polimerase/métodos , Sequência de Bases , Medula Óssea/patologia , Células Clonais , Formaldeído , Rearranjo Gênico , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias kappa de Imunoglobulina/genética , Linfonodos/patologia , Linfoma não Hodgkin/classificação , Linfoma não Hodgkin/genética , Dados de Sequência Molecular , Inclusão em Parafina , Receptores de Antígenos de Linfócitos T gama-delta/genética , Pele/patologia , Fixação de Tecidos , Proteína Supressora de Tumor p53/genéticaRESUMO
An understanding of the distribution of manganese ions in the brain is of interest in connection with the development of an understanding of the neurotoxicity of this element. Information about the time dependent biodistribution of manganese ions in the brains of intact rats subsequent to single IP injections of MnCl2 has been obtained from magnetic resonance imaging (MRI) studies. The enhanced MRI contrast is based on the reduction in the spin lattice relaxation time (T1) of water protons which exchange into the coordination sphere of the manganese ions. These studies indicate rapid and significant accumulations of water accessible manganese in the ventricles, the pineal gland, and the pituitary gland. The rapid appearance of high levels of manganese in the ventricular cerebrospinal fluid indicates that manganese readily crosses the filtration barrier of the choroid plexus and is thereafter apparently absorbed by the ependymal surfaces of the ventricles and transported to the subarachnoid space.
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Encéfalo/metabolismo , Cloretos , Compostos de Manganês , Manganês/farmacocinética , Anestesia , Animais , Barreira Hematoencefálica , Ventrículos Cerebrais/metabolismo , Imageamento por Ressonância Magnética , Masculino , Glândula Pineal/metabolismo , Hipófise/metabolismo , Ratos , Ratos EndogâmicosRESUMO
Seven stable nitroxides have been evaluated as contrast agents in MRI studies of the rat cerebroventricular system. Because the contrast enhancement is primarily confined to the cerebral ventricles, nitroxides can be used to examine the ventricular structure. On the other hand, based on the absence of reducing agents in the rat CSF and on the fact that nitroxides can be reduced intracellularly, the relative reduction in contrast subsequent to an intracerebral injection provides information on the relationship of chemical structure to transmembrane flux in vivo. Observed rate constants and rate constants due to reduction have been analyzed quantitatively by modeling the effects of flow with GdDTPA, which is not subject to reduction. Five-membered ring nitroxides, in general, were reduced at much slower rates than six-membered ring nitroxides. The presence of a positive charge in the structure can substantially slow down the transmembrane flux.
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Ventrículos Cerebrais/metabolismo , Meios de Contraste/farmacocinética , Imageamento por Ressonância Magnética , Óxidos de Nitrogênio/farmacocinética , Animais , Barreira Hematoencefálica , Gadolínio DTPA , Óxidos de Nitrogênio/química , Compostos Organometálicos , Ácido Pentético/análogos & derivados , Ratos , Fatores de TempoRESUMO
The importance of specific immunity, especially cell-mediated, in resistance to herpes simplex disease is well documented, and animal experiments show that immune responses to previous herpetic infection can give considerable protection against reinfection in epithelial keratitis. Since susceptibility to stromal herpetic keratitis is probably determined in part by the extent of virus proliferation in the epithelium, immune responses to herpes simplex virus were studied in patients with epithelial or stromal keratitis, a group of patients with keratitis who were also severely atopic, and controls. The parameters measured were lymphocyte transformation, production of macrophage migration inhibition factor, and levels of serum antibody and immunoglobulin. No group differences were found except for a slight decrease in the whole blood culture assessment of lymphocyte transformation in stromal keratitis patients compared with seropositive controls and patients with epithelial disease. It is considered that in a small group of patients a deficiency in the specific cell-mediated immune response plays a role in determining the spread of virus into the corneal stroma.
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Anticorpos Antivirais/biossíntese , Imunidade Celular , Ceratite Dendrítica/imunologia , Adolescente , Adulto , Idoso , Testes de Fixação de Complemento , Feminino , Humanos , Hipersensibilidade Imediata/imunologia , Imunoglobulinas/análise , Terapia de Imunossupressão , Cinética , Ativação Linfocitária , Fatores Inibidores da Migração de Macrófagos/biossíntese , Masculino , Pessoa de Meia-Idade , RecidivaRESUMO
Divalent cadmium and mercury ions are capable in vitro of displacement of zinc from metallothionein. This process has now been studied in vivo and ex vivo, using the isolated perfused rat liver system, in order to determine if this process can occur in the intact cell. Rats with normal and elevated (via preinduction with zinc) levels of hepatic zinc thionein were studied. Cd(II) completely displaces zinc from normal levels of metallothionein and on a one-to-one basis from elevated levels of metallothionein, both in vivo and ex vivo. Hg(II) displaces zinc from metallothionein (normal or elevated) rather poorly, as compared with Cd(II), in vivo, probably due to the kidneys preference for absorbing this metal. Ex vivo Hg(II) displaces zinc from metallothionein (normal or elevated) on a one-to-one basis, with considerably more mercury being incorporated into the protein than in vivo. The results of double-label ex vivo experiments using metal and [35S]cysteine (+/- cycloheximide) were consistent with the above experiments, indicating that de novo thionein synthesis was not required for short term incorporation of cadmium and mercury into metallothionein. These data are supportive of the hypothesis that cadmium and mercury incorporation into rat hepatic metallothionein during the first few hours after exposure to these metals can occur primarily by displacement of zinc from preexisting zinc thionein by a process which does not require new protein synthesis.
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Cádmio/metabolismo , Mercúrio/metabolismo , Metalotioneína/metabolismo , Zinco/metabolismo , Animais , Ligação Competitiva , Cicloeximida/farmacologia , Técnicas In Vitro , Cinética , Fígado/efeitos dos fármacos , Masculino , Ratos , Ratos Endogâmicos , Zinco/farmacologiaRESUMO
The aim of our study was to describe the development of uteroplacental and fetal blood flow during the third trimester. Doppler examination was carried out on 393 uncomplicated pregnancies with uncomplicated term delivery. Using a pulsed color Doppler, we calculated the maximum systolic, mean and maximum end-diastolic velocity after correcting the angle of insonation. Patients under tocolysis or other medication influencing blood flow parameters were excluded from this cross-sectional study. Summarizing the results gained by Doppler ultrasound investigation of the uteroplacental and fetal blood vessels, we created quantiles as quantitative Doppler indices for the maximum systolic, mean (TAMX = time averaged maximum velocity) and maximum end-diastolic velocity. The following conclusions could be drawn: (1) resistance to the blood flow in the maternal portion of the placenta does not change during the third trimester; (2) resistance to the blood flow on the fetal side of the placenta decreases up to week 42 of gestation; (3) cerebral vascular resistance decreases constantly up to gestational week 42; and (4) vascular resistance to the blood flow of the kidney decreases only slightly during the third trimester. This study offers clinically important values for quantitative Doppler flow velocimetry for the first time. We hope that our findings improve the usefulness of Doppler ultrasound as a diagnostic tool in obstetrical management.
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Velocidade do Fluxo Sanguíneo , Feto/fisiologia , Circulação Placentária , Ultrassonografia Doppler , Artérias Cerebrais/fisiologia , Estudos Transversais , Diástole , Feminino , Idade Gestacional , Humanos , Gravidez , Terceiro Trimestre da Gravidez , Valores de Referência , Artéria Renal/fisiologia , Sístole , Artérias Umbilicais/fisiologia , Útero/irrigação sanguínea , Resistência VascularRESUMO
OBJECTIVE: Conventional transvaginal ultrasound-and transvaginal colour Doppler flow were used to assess morphology and circulation of pelvic masses. STUDY DESIGN: One hundred and nine adnexal masses in 101 women were examined between January 1993 and September 1994. Morphology was classified after a score published by Sassone et al. in 1991. Doppler waveforms using the lowest resistance index (RI), the pulsatility index (PI) and peak flow velocity were used for analysis. Ninety five patients underwent laparotomy. Following histopathological evaluation best cut-off values, sensitivity and specificity were calculated. Score results were compared with Doppler results and a combination of both methods. RESULTS: A combination of Doppler sonography and conventional transvaginal sonography led to a sensitivity of 74.0% and a specificity of 73.7%. Eight out of 15 malignant masses were classified as stage I. An analysis of the false positive diagnoses showed that important information can be gained when Doppler sonography is performed. In particular, on solid appearing adnexal masses, Doppler sonography leads to a high accuracy (84.6%). CONCLUSION: Colour Doppler sonography is not applicable in routine clinical practice, but can give important additional information in specific cases. For solid appearing masses and in early ovarian malignancy, Doppler sonography facilitates the preoperative discrimination between benign and malignant processes.
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Neoplasias Ovarianas/diagnóstico por imagem , Ultrassonografia Doppler em Cores , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/cirurgia , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Ultrassonografia/métodos , VaginaRESUMO
Arthroscopy of the temporomandibular joint (TMJ) has become a clinically important and increasingly accepted method for diagnosis and treatment of TMJ alteration. This minimally invasive method is clearly limited by the anatomic dimensions of the TMJ. The 308-nm excimer laser has already found clinical applications in angioplasty, ophthalmology, and dentistry. This study aimed to find out whether it is possible to ablate TMJ-related structures under arthroscopic conditions. It also aimed to determine the energy threshold for ablation and the maximum rate of ablation. By histologic investigation of the irradiated tissues, the amount of tissue alteration was determined. TMJ structures of freshly slaughtered pigs served as tissue samples. The 308-nm excimer laser light was guided through optical fibers. The tissue was irradiated under continuous flow of saline solution. The energy threshold for ablation of TMJ structures was found at about 1 J/cm2. The maximum rate of ablation was found at 3-5 micron/pulse, depending on the type of tissue. The amount of tissue alteration varied between 1 and 150 microns. The types of tissue alteration were vacuolization and hyalinization. The results of the investigations described indicate that the 308-nm excimer laser is an ideal tool for TMJ arthroscopic surgery. Unlike other laser systems, it offers a unique combination of minimal tissue alteration, precise tissue ablation, guidability through optical fibers, and good transmission through water. This makes possible endoscopic removal of free bodies, adhesions, exostoses, and appositions in a minimally invasive surgical procedure.
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Terapia a Laser/métodos , Articulação Temporomandibular/cirurgia , Animais , Artroscopia , SuínosRESUMO
We report on Doppler sonographic findings of a dialysis patient with renal anemia during otherwise uncomplicated pregnancy. Uteroplacental and fetoplacental flow relationships before, as well as after the dialysis treatments during the course of the pregnancy were in the normal range. The favorable flow condition in the utero- and fetoplacental circulation was associated with a low hematocrit. This in accordance with previous reports indicates a more favorable maternal and fetal outcome in association with a low hematocrit/hemoglobin concentration.