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1.
Z Geburtshilfe Neonatol ; 227(2): 147-150, 2023 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-36764309

RESUMO

We report on the obstetric and neonatal course of a 34-year-old woman pregnant with twins, who presented at our clinic at 16+1 weeks of gestation with preterm premature rupture of membranes. We started intravenous antibiotic therapy with inpatient monitoring owing to the vitality and regular development of both twins, with anhydramnios in the leading twin. After a missed abortion of the leading twin at 19+1 weeks of gestation we decided on surgical intervention with assisted delivery of the aborted twin, leaving the placenta in situ with subsequent emergency total cervical occlusion. Afterwards, the single pregnancy could be continued until the 24th week of gestation. An urgent Caesarean section for early labor, premature rupture of membranes, and increasing signs of maternal infection was later performed. Overall, the postnatal course of the extremely preterm neonate was a success considering the gestational age. We conclude that the option of surgical interventions should be taken into account in similar cases in the future.


Assuntos
Trabalho de Parto , Nascimento Prematuro , Recém-Nascido , Gravidez , Humanos , Feminino , Adulto , Cesárea , Lactente Extremamente Prematuro , Idade Gestacional , Gravidez de Gêmeos
2.
Arch Gynecol Obstet ; 303(2): 471-479, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33000294

RESUMO

PURPOSE: Patients with pelvic floor disorders are growing in number. The aim of this study is to outline the main activities of a urotherapist, an advanced nurse practitioner, in the care of patients with pelvic floor disorders and to evaluate patient satisfaction with the service urotherapists provide. METHODS: The prospective single-center observational study was carried out from July 2016 to June 2018. Parameters used to assess the urotherapist activities included the number of consultations, type of counselling, time frame of consultations and therapy and patient satisfaction. In a subgroup of 38 patients, satisfaction with the urotherapy sessions was evaluated by a questionnaire. RESULTS: Totally, 1709 patients were examined by urogynecologists. Five hundred and fourteen (30%) with chronic pelvic floor disorders were subsequently referred to a urotherapist. Of these patients, 60% were at least 65 years old. The most common pelvic floor disorders (221 patients; 43%) were an overactive bladder, recurrent urinary tract infections, chronic cystitis and pelvic pain syndrome; the second most common pelvic floor disorder was pelvic organ prolapsed (151 patients; 29%). Of the study subgroup comprising 38 patients, 32 (84%) returned the patient satisfaction questionnaire. All 32 patients specified their level of agreement with the urotherapist's professional competence, empathy, temporal availability and quality of advice as "agree to strongly agree." CONCLUSIONS: Management by a urotherapist was highly appreciated. The role of the urotherapist as a care coordinator, their level of autonomy and barriers to the implementation in primary care requires further exploration.


Assuntos
Força Muscular/fisiologia , Profissionais de Enfermagem/psicologia , Satisfação do Paciente/estatística & dados numéricos , Distúrbios do Assoalho Pélvico/reabilitação , Incontinência Urinária/reabilitação , Adulto , Prática Avançada de Enfermagem , Idoso , Comportamento Cooperativo , Feminino , Humanos , Relações Interprofissionais , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Assistência ao Paciente , Distúrbios do Assoalho Pélvico/epidemiologia , Prolapso de Órgão Pélvico/epidemiologia , Dor Pélvica/epidemiologia , Estudos Prospectivos , Inquéritos e Questionários , Bexiga Urinária Hiperativa/epidemiologia , Infecções Urinárias/epidemiologia
3.
Arch Toxicol ; 93(3): 743-751, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30659322

RESUMO

Boron-associated shifts in sex ratios at birth were suggested earlier and attributed to a decrease in Y- vs. X-bearing sperm cells. As the matter is pivotal in the discussion of reproductive toxicity of boron/borates, re-investigation in a highly borate-exposed population was required. In the present study, 304 male workers in Bandirma and Bigadic (Turkey) with different degrees of occupational and environmental exposure to boron were investigated. Boron was quantified in blood, urine and semen, and the persons were allocated to exposure groups along B blood levels. In the highest ("extreme") exposure group (n = 69), calculated mean daily boron exposures, semen boron and blood boron concentrations were 44.91 ± 18.32 mg B/day, 1643.23 ± 965.44 ng B/g semen and 553.83 ± 149.52 ng B/g blood, respectively. Overall, an association between boron exposure and Y:X sperm ratios in semen was not statistically significant (p > 0.05). Also, the mean Y:X sperm ratios in semen samples of workers allocated to the different exposure groups were statistically not different in pairwise comparisons (p > 0.05). Additionally, a boron-associated shift in sex ratio at birth towards female offspring was not visible. In essence, the present results do not support an association between boron exposure and decreased Y:X sperm ratio in males, even under extreme boron exposure conditions.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Boro/toxicidade , Exposição Ocupacional/análise , Adulto , Cromossomos Humanos X , Cromossomos Humanos Y , Humanos , Masculino , Reprodução , Razão de Masculinidade , Espermatozoides/efeitos dos fármacos , Turquia
4.
Arch Toxicol ; 92(8): 2475-2485, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29947890

RESUMO

Boric acid and sodium borates are currently classified as being toxic to reproduction under "Category 1B" with the hazard statement of "H360 FD" in the European CLP regulation. This has prompted studies on boron-mediated reprotoxic effects in male workers in boron mining areas and boric acid production plants. By contrast, studies on boron-mediated developmental effects in females are scarce. The present study was designed to fill this gap. Hundred and ninety nine females residing in Bandirma and Bigadic participated in this study investigating pregnancy outcomes. The participants constituted a study group covering blood boron from low (< 100 ng B/g blood, n = 143) to high (> 150 ng B/g blood, n = 27) concentrations. The mean blood boron concentration and the mean estimated daily boron exposure of the high exposure group was 274.58 (151.81-975.66) ng B/g blood and 24.67 (10.47-57.86) mg B/day, respectively. In spite of the high level of daily boron exposure, boron-mediated adverse effects on induced abortion, spontaneous abortion (miscarriage), stillbirth, infant death, neonatal death, early neonatal death, preterm birth, congenital anomalies, sex ratio and birth weight of newborns were not observed.


Assuntos
Peso ao Nascer/efeitos dos fármacos , Boro/sangue , Contaminação de Alimentos/análise , Exposição Materna/efeitos adversos , Resultado da Gravidez/epidemiologia , Poluentes Químicos da Água/sangue , Boro/efeitos adversos , Boro/urina , Feminino , Humanos , Recém-Nascido , Modelos Lineares , Gravidez , Turquia , Poluentes Químicos da Água/efeitos adversos , Poluentes Químicos da Água/urina
5.
Arch Toxicol ; 92(10): 3051-3059, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30143848

RESUMO

Boric acid and sodium borates are currently classified in the EU-CLP regulation as "toxic to reproduction" under "Category 1B", with hazard statement of H360FD. However, so far field studies on male reproduction in China and in Turkey could not confirm such boron-associated toxic effects. As validation by another independent study is still required, the present study has investigated possible boron-associated effects on male reproduction in workers (n = 212) under different boron exposure conditions. The mean daily boron exposure (DBE) and blood boron concentration of workers in the extreme exposure group (n = 98) were 47.17 ± 17.47 (7.95-106.8) mg B/day and 570.6 ± 160.1 (402.6-1100) ng B/g blood, respectively. Nevertheless, boron-associated adverse effects on semen parameters, as well as on FSH, LH and total testosterone levels were not seen, even within the extreme exposure group. With this study, a total body of evidence has accumulated that allows to conclude that male reproductive effects are not relevant to humans, under any feasible and realistic conditions of exposure to inorganic boron compounds.


Assuntos
Boro/toxicidade , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Exposição Ocupacional/efeitos adversos , Testosterona/sangue , Adulto , Poluentes Ocupacionais do Ar/análise , Poluentes Ocupacionais do Ar/toxicidade , Boro/análise , Boro/urina , Indústria Química , Humanos , Masculino , Mineração , Exposição Ocupacional/análise , Sêmen/efeitos dos fármacos , Motilidade dos Espermatozoides/efeitos dos fármacos , Turquia
6.
Am J Physiol Heart Circ Physiol ; 304(6): H786-95, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23292715

RESUMO

This study aims to identify the potential mechanisms by which perivascular adipose tissue (PVAT) reduces tone in small arteries. Small mesenteric arteries from wild-type and large-conductance Ca(2+)-activated K(+) (BKCa) channel knockout mice were mounted on a wire myograph in the presence and absence of PVAT, and contractile responses to norepinephrine were assessed. Electrophysiology studies were performed in isolated vessels to measure changes in membrane potential produced by adiponectin. Contractile responses from wild-type mouse small arteries were significantly reduced in the presence of PVAT. This was not observed in the presence of a BKCa channel inhibitor or with nitric oxide synthase (NOS) inhibition or in BKCa or adiponectin knockout mice. Solution transfer experiments demonstrated the presence of an anticontractile factor released from PVAT. Adiponectin-induced vasorelaxation and hyperpolarization in wild-type arteries were not evident in the absence of or after inhibition of BKCa channels. PVAT from BKCa or adiponectin knockout mice failed to elicit an anticontractile response in wild-type arteries. PVAT releases adiponectin, which is an anticontractile factor. Its effect on vascular tone is mediated by activation of BKCa channels on vascular smooth muscle cells and adipocytes and by endothelial mechanisms.


Assuntos
Adiponectina/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Alta/fisiologia , Contração Muscular/efeitos dos fármacos , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Animais , Canais de Potássio Ativados por Cálcio de Condutância Alta/agonistas , Canais de Potássio Ativados por Cálcio de Condutância Alta/genética , Potenciais da Membrana , Artérias Mesentéricas/metabolismo , Artérias Mesentéricas/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/fisiologia , Óxido Nítrico/antagonistas & inibidores , Norepinefrina/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Vasoconstritores/farmacologia , Vasodilatação
7.
World J Urol ; 31(5): 1111-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22249342

RESUMO

PURPOSE: To evaluate the accuracy of presurgical endorectal MRI (eMRI) for local staging before radical prostatectomy (RP) and its influence on neurovascular bundle (NVB) resection during radical prostatectomy. PATIENTS AND METHODS: A total of 385 patients with histologically proven prostate cancer (PCa) have been included in this retrospective study between 2004 and 2008. All patients underwent preoperative eMRI at 1.5 T before open RP. Staging results by eMRI were compared with the histopathological findings. The presence of positive surgical margins and extent of nerve-sparing procedure were evaluated. Subgroup analysis of low-risk group and intermediate to high-risk group based on D'Amico criteria was conducted. RESULTS: In 294 (76.4%) patients, pathological stage was correctly predicted, 69 patients (17.9%) were understaged and 22 (5.7%) overstaged. Overall sensitivity, specificity, negative and positive predictive value for predicting extracapsular extension (ECE) were 41.5, 91.8, 78.0 and 69.0%, respectively. One hundred and fifty-two (48.4%) of the patients classified as stage cT2 by eMRI underwent bilateral NVB sparing, whereas 14 (19.7%) patients with reported ECE underwent bilateral NVB sparing (P < 0.01). Overall positive surgical margin rate was 14.8%. Sensitivity of predicting ECE and positive predictive value were lower in the low-risk group than in the intermediate and high-risk group. CONCLUSIONS: eMRI is effective in predicting extracapsular extension in an intermediate to high-risk group. Preoperative eMRI in patients with low-risk criteria is not recommended as a routine assessment modality. eMRI findings did appear to influence surgical strategy as patients with imaging findings suggesting >cT2 disease were less likely to undergo NVB sparing.


Assuntos
Imageamento por Ressonância Magnética/métodos , Tratamentos com Preservação do Órgão/métodos , Cuidados Pré-Operatórios , Próstata/inervação , Prostatectomia/métodos , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Seleção de Pacientes , Valor Preditivo dos Testes , Próstata/patologia , Próstata/cirurgia , Reto , Estudos Retrospectivos , Fatores de Risco , Sensibilidade e Especificidade
8.
J Cancer Res Clin Oncol ; 149(5): 1961-1967, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35980483

RESUMO

PURPOSE: The course of osteosarcoma patients primarily treated as such has been well described. Little, however, is known about patients who were primarily treated assuming a different tumor diagnosis. METHODS: The database of the Cooperative Osteosarcoma Study Group COSS was searched (4.435 primary high-grade central osteosarcomas registered prior to 01/01/21). A different tumor entity had to have been assumed for at least one month after the initial diagnostic procedure before the correct diagnosis of osteosarcoma was finally made. Identified patients were analyzed for demographic, tumor-, and treatment-related factors as well as for survival outcomes. RESULTS: 37 patients were identified. They were a median of 19.7 (2.7-60.4) years old at first presentation and were more likely to be females than males (23:14). Bone cysts (n = 8), giant cell tumor of bone (n = 6), and osteoblastoma (n = 6) were the most frequent of 29/37 (78%) benign, chondrosarcoma and its variants (n = 6) the most frequent of 8/37 (22%) malignant original diagnoses. Tumors affected the extremities in 23 (62%), the trunk in 11 (30%), and the craniofacial bones in 3 (8%). Only one patient received systemic treatment while assuming the different diagnosis (1/37, 3%). The median time until the correct diagnosis of osteosarcoma was made was 8 months (range: 1 month-14.1 years). At that time, 6/37 (16%) presented with metastatic disease. All patients went on to receive chemotherapy, 17/37 (46%) neo-adjuvantly. Histologic response was only evaluated in 13/17 (76%) patients and was good (< 10% viable tumor) in only 4/13 (31%) patients. In 31/37 (84%) patients, a surgically complete resection of all macroscopically identified tumor manifestations could be achieved. Five-year overall and event-free survival rates at 5 years were 50.2% (standard error: 8.6%) and 42.6% (8.5%), respectively. CONCLUSION: Osteosarcoma may initially be misdiagnosed and hence subjected to inappropriate treatment including misguided surgery. Once diagnosed correctly, some of the affected patients may still be cured if finally treated according to modern osteosarcoma standards.


Assuntos
Neoplasias Ósseas , Segunda Neoplasia Primária , Osteossarcoma , Masculino , Feminino , Humanos , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Resultado do Tratamento , Neoplasias Ósseas/patologia , Osteossarcoma/terapia , Osteossarcoma/tratamento farmacológico , Intervalo Livre de Doença
9.
J Clin Oncol ; 41(27): 4323-4337, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37713812

RESUMO

PURPOSE: To define prognostic factors for response and long-term outcome for a wide spectrum of osteosarcomas, extending well beyond those of the typical young patient with seemingly localized extremity disease. PATIENTS AND METHODS: A total of 1,702 consecutive newly diagnosed patients with high-grade osteosarcoma of the trunk or limbs registered into the neoadjuvant studies of the Cooperative Osteosarcoma Study Group before July 1998 were entered into an analysis of demographic, tumor-related, and treatment-related variables, response, and survival. The intended therapeutic strategy included preoperative and postoperative chemotherapy with multiple agents as well as surgery of all operable lesions. RESULTS: Axial tumor site, male sex, and a long history of symptoms were associated with poor response to chemotherapy in univariate and multivariate analysis. Actuarial 10-year overall and event-free survival rates were 59.8% and 48.9%. Among the variables assessable at diagnosis, patient age (actuarial 10-year survival ≥ 40, 41.6%; < 40, 60.2%; P = .012), tumor site (axial, 29.2%; limb, 61.7%; P < .0001), and primary metastases (yes, 26.7%; no, 64.4%; P < .0001), and for extremity osteosarcomas, also size (≥ one third, 52.5%; < one third, 66.7%; P < .0001) and location within the limb (proximal, 49.3%; other, 63.9%; P < .0001), had significant influence on outcome. Two additional important prognostic factors were treatment related: response to chemotherapy (poor, 47.2%; good, 73.4%; P < .0001) and the extent of surgery (incomplete, 14.6%; macroscopically complete, 64.8%; P < .0001). All factors except age maintained their significance in multivariate testing, with surgical remission and histologic response emerging as the key prognostic factors. CONCLUSION: Tumor site and size, primary metastases, response to chemotherapy, and surgical remission are of independent prognostic value in osteosarcoma.

10.
Eur J Nucl Med Mol Imaging ; 39(11): 1756-66, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22890801

RESUMO

PURPOSE: Clinical PET/MR acquisition protocols entail the use of MR contrast agents (MRCA) that could potentially affect PET quantification following MR-based attenuation correction (AC). We assessed the effect of oral and intravenous (IV) MRCA on PET quantification in PET/MR imaging. METHODS: We employed two MRCA: Lumirem (oral) and Gadovist (IV). First, we determined their reference PET attenuation values using a PET transmission scan (ECAT-EXACT HR+, Siemens) and a CT scan (PET/CT Biograph 16 HI-REZ, Siemens). Second, we evaluated the attenuation of PET signals in the presence of MRCA. Phantoms were filled with clinically relevant concentrations of MRCA in a background of water and (18)F-fluoride, and imaged using a PET/CT scanner (Biograph 16 HI-REZ, Siemens) and a PET/MR scanner (Biograph mMR, Siemens). Third, we investigated the effect of clinically relevant volumes of MRCA on MR-based AC using human pilot data: a patient study employing Gadovist (IV) and a volunteer study employing two different oral MRCA (Lumirem and pineapple juice). MR-based attenuation maps were calculated following Dixon-based fat-water segmentation and an external atlas-based and pattern recognition (AT&PR) algorithm. RESULTS: IV and oral MRCA in clinically relevant concentrations were found to have PET attenuation values similar to those of water. The phantom experiments showed that under clinical conditions IV and oral MRCA did not yield additional attenuation of PET emission signals. Patient scans showed that PET attenuation maps are not biased after the administration of IV MRCA but may be biased, however, after ingestion of iron oxide-based oral MRCA when segmentation-based AC algorithms are used. Alternative AC algorithms, such as AT&PR, or alternative oral contrast agents, such as pineapple juice, can yield unbiased attenuation maps. CONCLUSION: In clinical PET/MR scenarios MRCA are not expected to lead to markedly increased attenuation of the PET emission signals. MR-based attenuation maps may be biased by oral iron oxide-based MRCA unless advanced AC algorithms are used.


Assuntos
Meios de Contraste/administração & dosagem , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Imagem Corporal Total , Administração Intravenosa , Administração Oral , Fluordesoxiglucose F18 , Humanos , Nanopartículas de Magnetita/administração & dosagem , Compostos Organometálicos/administração & dosagem , Siloxanas/administração & dosagem
11.
AJR Am J Roentgenol ; 199(2): 272-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22826387

RESUMO

OBJECTIVE: This article provides a short overview of hybrid imaging and the potential advantages of combined MR/PET. We will address some of the challenges that had to be met before MR/PET could become clinically available as well as further scientific work that has to be done to increase the potential benefit of this emerging hybrid modality. CONCLUSION: Hybrid imaging, the combination of two imaging modalities into one, promises the compensation of specific deficits of the modalities involved. PET/CT has gained wide acceptance for oncologic imaging in recent years; however, MRI has certain advantages that could make combined MR/PET more tempting in various clinical applications. The development of new clinical whole-body MR/PET systems offers new insights in metabolic and functional processes in oncology as well as cardiovascular and neurologic diseases.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Imagem Corporal Total , Meios de Contraste , Humanos , Imagem Multimodal , Neoplasias/patologia , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X
12.
Eur J Nucl Med Mol Imaging ; 38(5): 920-9, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21308373

RESUMO

OBJECTIVES: Clinical PET/MR requires the use of patient positioning aids to immobilize and support patients for the duration of the combined examination. Ancillary immobilization devices contribute to overall attenuation of the PET signal, but are not detected with conventional MR sequences and, hence, are ignored in standard MR-based attenuation correction (MR-AC). We report on the quantitative effect of not accounting for the attenuation of patient positioning aids in combined PET/MR imaging. METHODS: We used phantom and patient data acquired with positioning aids on a PET/CT scanner (Biograph 16, HI-REZ) to mimic PET/MR imaging conditions. Reference CT-based attenuation maps were generated from measured (original) CT transmission images (origCT-AC). We also created MR-like attenuation maps by following the same conversion procedure of the attenuation values except for the prior delineation and subtraction of the positioning aids from the CT images (modCT-AC). First, a uniform (68)Ge cylinder was positioned centrally in the PET/CT scanner and fixed with a vacuum mattress (10 cm thick) and, in a repeat examination, with MR positioning foam pads. Second, 16 patient datasets were selected for subsequent processing. All patients were regionally immobilized with positioning aids: a vacuum mattress for head/neck imaging (nine patients) and a foam mattress for imaging of the lower extremities (seven patients). PET images were reconstructed following CT-based attenuation and scatter correction using the original and modified (MR-like) CT images: PET(origCT-AC) and PET(modCT-AC), respectively. PET images following origCT-AC and modCT-AC were compared visually and in terms of mean differences of voxels with a standardized uptake value of at least 1.0. In addition, we report maximum activity concentration in lesions for selected patients. RESULTS: In the phantom study employing the vacuum mattress the average voxel activity in PET(modCT-AC) was underestimated by 6.4% compared to PET(origCT-AC), with 3.4% of the PET voxels being underestimated by 10% or more. When the MR foam pads were not accounted for during AC, PET(modCT-AC) was underestimated by 1.1% on average, with none of the PET voxels being underestimated by 10% or more. Evaluation of the head/neck patient data showed a decrease of 8.4% ([(68)Ga]DOTATOC) and 7.4% ([(18)F]FDG) when patient positioning aids were not accounted for during AC, while the corresponding decrease was insignificant for the lower extremities. CONCLUSION: Depending on the size and density of the positioning aids used, a regionally variable underestimation of PET activity following AC is observed when positioning aids are not accounted for. This underestimation may become relevant in combined PET/MR imaging of patients with neuropsychiatric indications, but appears to be of no clinical relevance in imaging the extremities.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Posicionamento do Paciente/métodos , Tomografia por Emissão de Pósitrons/métodos , Humanos , Imagens de Fantasmas , Estudos Retrospectivos
13.
J Physiol ; 587(Pt 21): 5275-88, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19736301

RESUMO

Contraction of urinary bladder smooth muscle (UBSM) is caused by the release of ATP and ACh from parasympathetic nerves. Although both purinergic and muscarinic pathways are important to contraction, their relative contributions and signalling mechanisms are not well understood. Here, the contributions of each pathway to urinary bladder contraction and the underlying electrical and Ca(2+) signalling events were examined in UBSM strips from wild type mice and mice deficient in P2X1 receptors (P2X1(-/-)) before and after pharmacological inhibition of purinergic and muscarinic receptors. Electrical field stimulation was used to excite parasympathetic nerves to increase action potentials, Ca(2+) flash frequency, and force. Loss of P2X1 function not only eliminated action potentials and Ca(2+) flashes during stimulation, but it also led to a significant increase in Ca(2+) flashes following stimulation and a corresponding increase in the force transient. Block of muscarinic receptors did not affect action potentials or Ca(2+) flashes during stimulation, but prevented them following stimulation. These findings indicate that nerve excitation leads to rapid engagement of smooth muscle P2X1 receptors to increase action potentials (Ca(2+) flashes) during stimulation, and a delayed increase in excitability in response to muscarinic receptor activation. Together, purinergic and muscarinic stimulation shape the time course of force transients. Furthermore, this study reveals a novel inhibitory effect of P2X1 receptor activation on subsequent increases in muscarinic-driven excitability and force generation.


Assuntos
Potenciais de Ação/fisiologia , Sinalização do Cálcio/fisiologia , Contração Muscular/fisiologia , Músculo Liso/inervação , Músculo Liso/fisiologia , Receptores Purinérgicos P2/metabolismo , Bexiga Urinária/inervação , Bexiga Urinária/fisiologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Inibição Neural/fisiologia , Receptores Purinérgicos P2X
14.
J Cell Biol ; 159(3): 489-98, 2002 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-12417579

RESUMO

Previous in vitro studies using cGMP or cAMP revealed a cross-talk between signaling mechanisms activated by axonal guidance receptors. However, the molecular elements modulated by cyclic nucleotides in growth cones are not well understood. cGMP is a second messenger with several distinct targets including cGMP-dependent protein kinase I (cGKI). Our studies indicated that the alpha isoform of cGKI is predominantly expressed by sensory axons during developmental stages, whereas most spinal cord neurons are negative for cGKI. Analysis of the trajectories of axons within the spinal cord showed a longitudinal guidance defect of sensory axons within the developing dorsal root entry zone in the absence of cGKI. Consequently, in cGKI-deficient mice, fewer axons grow within the dorsal funiculus of the spinal cord, and lamina-specific innervation, especially by nociceptive sensory neurons, is strongly reduced as deduced from anti-trkA staining. These axon guidance defects in cGKI-deficient mice lead to a substantial impairment in nociceptive flexion reflexes, shown using electrophysiology. In vitro studies revealed that activation of cGKI in embryonic dorsal root ganglia counteracts semaphorin 3A-induced growth cone collapse. Our studies therefore reveal that cGMP signaling is important for axonal growth in vivo and in vitro.


Assuntos
Axônios/fisiologia , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Neurônios Aferentes/fisiologia , Sistemas do Segundo Mensageiro/fisiologia , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Potenciais de Ação/fisiologia , Animais , Técnicas de Cultura , GMP Cíclico/análogos & derivados , Proteínas Quinases Dependentes de GMP Cíclico/genética , Estimulação Elétrica , Embrião de Mamíferos/fisiologia , Gânglios Espinais/anatomia & histologia , Gânglios Espinais/metabolismo , Genótipo , Camundongos , Camundongos Endogâmicos , Camundongos Transgênicos , Neurônios Aferentes/citologia , Neurônios Aferentes/efeitos dos fármacos , Nociceptores , Isoformas de Proteínas , Semaforina-3A/farmacologia , Medula Espinal/anatomia & histologia , Medula Espinal/metabolismo
15.
Eur Radiol ; 19(1): 37-41, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18648818

RESUMO

The aim of the study was to evaluate radiation exposure of a chest pain protocol with ECG-gated dual-source computed tomography (DSCT). An Alderson Rando phantom equipped with thermoluminescent dosimeters was used for dose measurements. Exposure was performed on a dual-source computed tomography system with a standard protocol for chest pain evaluation (120 kV, 320 mAs/rot) with different simulated heart rates (HRs). The dose of a standard chest CT examination (120 kV, 160 mAs) was also measured. Effective dose of the chest pain protocol was 19.3/21.9 mSv (male/female, HR 60), 17.9/20.4 mSv (male/female, HR 80) and 14.7/16.7 mSv (male/female, HR 100). Effective dose of a standard chest examination was 6.3 mSv (males) and 7.2 mSv (females). Radiation dose of the chest pain protocol increases significantly with a lower heart rate for both males (p = 0.040) and females (p = 0.044). The average radiation dose of a standard chest CT examination is about 36.5% that of a CT examination performed for chest pain. Using DSCT, the evaluated chest pain protocol revealed a higher radiation exposure compared with standard chest CT. Furthermore, HRs markedly influenced the dose exposure when using the ECG-gated chest pain protocol.


Assuntos
Carga Corporal (Radioterapia) , Técnicas de Imagem de Sincronização Cardíaca , Dor no Peito/diagnóstico por imagem , Eficiência Biológica Relativa , Dosimetria Termoluminescente , Tomografia Computadorizada por Raios X/métodos , Humanos , Imagens de Fantasmas , Doses de Radiação , Tomografia Computadorizada por Raios X/instrumentação
16.
AJR Am J Roentgenol ; 193(3): W181-5, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19696256

RESUMO

OBJECTIVE: The aim of the study was to assess variations in the diameter of the common bile duct in patients with gastrointestinal graft-versus-host disease (GVHD) undergoing abdominal CT after allogeneic hematopoietic stem cell transplantation and to correlate the findings with laboratory results on cholestasis. MATERIALS AND METHODS: We performed a retrospective analysis of the caliber of the common bile duct in 27 adult patients with histologically validated gastrointestinal GVHD who underwent two or more follow-up abdominal CT examinations. Another 25 patients who underwent allogeneic hematopoietic stem cell transplantation during the same period at our institution but who did not have GVHD constituted the control group. The diameters of the common bile duct were correlated with cholestasis values. RESULTS: A pathologic diameter of the common bile duct was defined as greater than 7 mm (48 patients) in patients who had not undergone cholecystectomy and greater than 8 mm in those who had (four patients). The median diameter of the common bile duct was 7 mm (range, 4-14.8 mm) in the GVHD group and 5.8 mm (range, 3.9-10.2 mm) in the control group. Pathologic diameters of the common bile duct were found in 67% of the patients in the GVHD group and in 12% of the control group (p < 0.0001). The variation coefficient of the diameter of the common bile duct was 12.4% in the GVHD group (83 examinations) and 6.4% in the control group (92 examinations) (p < 0.0001). Ninety-six percent of the patients in the GVHD group had elevated cholestasis values with a significant positive correlation between bilirubin concentration and diameter of the common bile duct (r = 0.421; p = 0.032). Enhancement of the common bile duct and gallbladder wall was seen in the majority of GVHD patients but no controls (p < 0.0001). CONCLUSION: Temporary dilatation of the common bile duct seems to be a common finding in gastrointestinal GVHD after hematopoietic stem cell transplantation and correlates with bilirubin concentration. This knowledge of fluctuation in bile duct diameter can help to avoid unnecessary tests to evaluate for pathologic causes of biliary dilatation.


Assuntos
Ducto Colédoco/patologia , Doença Enxerto-Hospedeiro/patologia , Transplante de Células-Tronco Hematopoéticas , Doença Aguda , Adulto , Idoso , Bilirrubina/análise , Estudos de Casos e Controles , Colestase/diagnóstico por imagem , Colestase/etiologia , Colestase/patologia , Ducto Colédoco/diagnóstico por imagem , Meios de Contraste , Dilatação Patológica/diagnóstico por imagem , Dilatação Patológica/etiologia , Dilatação Patológica/patologia , Feminino , Doença Enxerto-Hospedeiro/complicações , Doença Enxerto-Hospedeiro/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
17.
AJR Am J Roentgenol ; 193(6): 1640-5, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19933659

RESUMO

OBJECTIVE: The aim of this study was to evaluate prospectively the effects of respiratory gating during FDG PET/CT on the determination of lesion size and the measurement of tracer uptake in patients with pulmonary nodules in a clinical setting. SUBJECTS AND METHODS: Eighteen patients with known pulmonary nodules (nine women, nine men; mean age, 61.4 years) underwent conventional FDG PET/CT and respiratory-gated PET acquisitions during their scheduled staging examinations. Maximum, minimum, and average standardized uptake values (SUVs) and lesion size and volume were determined with and without respiratory gating. The results were then compared using the two-tailed Student's t test and the nonparametric Wilcoxon's test to assess the effects of respiratory gating on PET acquisitions. RESULTS: Respiratory gating reduced the measured area of lung lesions by 15.5%, the axial dimension by 10.3%, and the volume by 44.5% (p = 0.014, p = 0.007, and p = 0.025, respectively). The lesion volumes in gated studies were closer to those assessed by standard CT (difference decreased by 126.6%, p = 0.025). Respiratory gating increased the measured maximum SUV by 22.4% and average SUV by 13.3% (p < 0.001 and p = 0.002). CONCLUSION: Our findings suggest that the use of PET respiratory gating in PET/CT results in lesion volumes closer to those assessed by CT and improved measurements of tracer uptake for lesions in the lungs.


Assuntos
Tomografia por Emissão de Pósitrons/métodos , Técnicas de Imagem de Sincronização Respiratória/métodos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fluordesoxiglucose F18 , Humanos , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade , Estatísticas não Paramétricas
18.
Wien Klin Wochenschr ; 131(13-14): 321-328, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31069475

RESUMO

BACKGROUND: Pulse index continuous cardiac output (PiCCO) is used for hemodynamic assessment. This study describes real world extravascular lung water index (EVLWI) measurements at three time points and relates them to other hemodynamic parameters and mortality in critically ill patients admitted to a medical intensive care unit (ICU). METHODS: A total of 198 patients admitted to a tertiary medical university hospital between February 2004 and December 2010 were included in this retrospective analysis. Patients were admitted for various diseases such as sepsis (n = 22), myocardial infarction (n = 53), pulmonary embolism (n = 3), cardiopulmonary resuscitation (n = 15), acute heart failure (AHF; n = 21) and pneumonia (n = 25). RESULTS: Patients included in this analysis were severely ill as represented by the high simplified acute physiology score 2 (SAPS2, 42 ± 18) and acute physiology and chronic health evaluation score 2 (APACHE2' 22 ± 9). Real-world values at three time points are provided. Intra-ICU mortality rates did not differ between the EVLWI > 7 vs. the ELVWI < 7 groups (15% vs. 13%; p = 0.82) and no association between hemodynamic measurements obtained by PiCCO with long-term mortality could be shown. CONCLUSION: There were no associations of any PiCCO measurements with mortality most probably due to selection bias towards severely ill patients. Future prospective studies with predefined inclusion criteria and treatment algorithms are necessary to evaluate the value of PiCCO for prediction of mortality against simple clinical tools such as jugular venous pressure, edema and auscultation.


Assuntos
Débito Cardíaco , Estado Terminal , Água Extravascular Pulmonar , Idoso , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Estudos Prospectivos , Estudos Retrospectivos , Termodiluição
19.
Artigo em Inglês | MEDLINE | ID: mdl-31421736

RESUMO

Industrial production and use of boron compounds have increased during the last decades, especially for the manufacture of borosilicate glass, fiberglass, metal alloys and flame retardants. This study was conducted in two districts of Balikesir; Bandirma and Bigadic, which geographically belong to the Marmara Region of Turkey. Bandirma is the production and exportation zone for the produced boric acid and some borates and Bigadic has the largest B deposits in Turkey. 102 male workers who were occupationally exposed to boron from Bandirma and 110 workers who were occupationally and environmentally exposed to boron from Bigadic participated to our study. In this study the DNA damage in the sperm, blood and buccal cells of 212 males was evaluated by comet and micronucleus assays. No significant increase in the DNA damage in blood, sperm and buccal cells was observed in the residents exposed to boron both occupationally and environmentally (p = 0.861) for Comet test in the sperm samples, p = 0.116 for Comet test in the lymphocyte samples, p = 0.042 for micronucleus (MN) test, p = 0.955 for binucleated cells (BN), p = 1.486 for condensed chromatin (CC), p = 0.455 for karyorrhectic cells (KHC), p = 0.541 for karyolitic cells (KLY), p = 1.057 for pyknotic cells (PHC), p = 0.331 for nuclear bud (NBUD)). No correlations were seen between blood boron levels and tail intensity values of the sperm samples, lymphocyte samples, frequencies of MN, BN, KHC, KYL, PHC and NBUD. The results of this study came to the same conclusions of the previous studies that boron does not induce DNA damage even under extreme exposure conditions.


Assuntos
Boro/toxicidade , Ensaio Cometa , Dano ao DNA , Células Epidérmicas/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Mucosa Bucal/citologia , Espermatozoides/efeitos dos fármacos , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Monitoramento Biológico , Boro/sangue , Fatores de Confusão Epidemiológicos , Células Epidérmicas/química , Humanos , Linfócitos/química , Masculino , Testes para Micronúcleos , Exposição Ocupacional , Fumar/epidemiologia , Espermatozoides/química , Inquéritos e Questionários , Fatores de Tempo , Turquia
20.
J Comput Biol ; 2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-30204481

RESUMO

The significance of alignment scores of optimally aligned DNA sequences can be estimated through the score distribution of pairs of random sequences. It is necessary to obtain statistics for the relevant high-scoring tail of the distribution. For local alignments of iid drawn sequences it has already been shown that the often assumed Gumbel distribution does not hold in the distribution tail, but has to be corrected by a Gaussian factor. Real DNA sequences were observed to show long-range correlations within sequences, which are not correctly modeled by iid random sequences. In this publication the large deviation method that was used in previous studies is applied to local and global alignment of such sequences with long-range correlations. We study the distributions over the full range of the support and obtained probabilities as low as [Formula: see text]. We show that again a correction to the Gumbel distribution is necessary to study the dependence of the parameters on the correlation strength. For global alignments the Gamma distribution, which was found heuristically to be a good fit in earlier simple sampling studies, is found to be a poor fit.

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