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1.
Photoacoustics ; 30: 100464, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36936710

RESUMO

Longitudinal acoustic modes in planar thin gold films are excited and detected by a combination of ultrafast pump-probe photoacoustic spectroscopy and a surface plasmon resonance (SPR) technique. The resulting high sensitivity allows the detection of acoustic modes up to the 7th harmonic (258 GHz) with sub-pm amplitude sensing capabilities. This makes a comparison of damping times of individual modes possible. Further, the dynamics of the real and imaginary part of the dielectric function and the film's thickness variation are separated by using the dependence of the amplitudes of the acoustic modes on the detection angle and the surface plasmon resonance. We find that longitudinal acoustic modes in the gold films mainly affect the real part of the dielectric function and highlight the importance to consider thickness related effects in acousto-plasmonic sensing.

2.
BJOG ; 128(7): 1184-1191, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33152167

RESUMO

OBJECTIVE: To systematically categorise all maternal and fetal intervention-related complications after open fetal myelomeningocele (fMMC) repair of the first 124 cases operated at the Zurich Centre for Fetal Diagnosis and Therapy. DESIGN: A prospective cohort study. SETTING: Single centre. POPULATION: Mothers and fetuses after fMMC repair. METHODS: Between 2010 and 2019, we collected and entered all maternal complications following fMMC repair into the Clavien-Dindo classification. For fetal complications, a classification system based on the Medical Dictionary for Regulatory Activities terminology of Adverse Events was used including the preterm definitions of the World Health Organization. MAIN OUTCOME MEASURES: Systematic classification of maternal and fetal complications following fMMC repair. RESULTS: Gestational ages at surgery and birth were 25.0 ± 0.8 and 35.4 ± 2.0 weeks, respectively. In 17% of all cases, no maternal complications occurred. Maternal intervention-related complications were observed as follows: 69% grade 1, 36% grade 2, 25% grade 3, 6% grade 4 and 0% grade 5. In 34%, no fetal complications were noted; however, 43% of the fetuses developed a grade 1, 14% a grade 2, 8% a grade 3, 2% a grade 4 and 2% a grade 5 complication. CONCLUSION: This study raises awareness of complications following open fMMC repair; 6% of mothers and 2% of fetuses experienced a severe complication (grade 4) and perinatal death rate of 2% was observed (grade 5). These data are useful for prenatal counselling, they help to improve the system of fetal surgical care, and they allow benchmarking with other centres as well as comparison with fetoscopic approaches. TWEETABLE ABSTRACT: Systematic classification of all maternal and fetal intervention-related complications following open fMMC repair.


Assuntos
Feto/cirurgia , Meningomielocele/cirurgia , Complicações Pós-Operatórias/classificação , Complicações na Gravidez/classificação , Estudos de Coortes , Feminino , Morte Fetal , Idade Gestacional , Humanos , Gravidez , Nascimento Prematuro
4.
Neotrop Entomol ; 46(3): 295-301, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28000065

RESUMO

The external morphology and genitalia of the males of Stenonartonia mimica (Kohl 1907), Sphaeromenes discrepatus Giordani Soika, 1978 and Gamma bolivianum flavior Giordani Soika, 1990 are described for the first time.


Assuntos
Vespas , Animais , Masculino , Vespas/anatomia & histologia , Vespas/classificação
7.
Neotrop Entomol ; 43(2): 97-105, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27193515

RESUMO

Vespoidea are the most functionally diverse superfamily of Hymenoptera. Ecological studies involving this family are primarily based on eusocial groups, including ants and social paper wasps. In the present study, we examine stinging wasp (Vespoidea) faunal diversity in the Atlantic Rain Forest, which is one of the most diverse and threatened ecosystems in the World. Three conservation areas were sampled employing a standardized sample protocol. Families and functional groups of Vespoidea were collected in each area, with the exception ants (Formicidae), and analyzed using diversity analyses, to generate taxonomic diversity and distinctness indices. Results indicated Pompilidae was the most diverse family, and the idiobiont parasitoid type was the most diverse functional group in the three study areas. Núcleo Picinguaba of the Parque Estadual da Serra do Mar was taxonomically and functionally the most diverse and species rich area. Parque Estadual Intervales showed the highest number of dominant species and diversity of koinobiont parasitoids, while the Rebio Sooretama exhibited a decrease in several diversity parameters.


Assuntos
Biodiversidade , Floresta Úmida , Vespas , Animais , Formigas , Brasil , Ecossistema
8.
Neotrop Entomol ; 43(2): 134-42, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27193520

RESUMO

This study aimed at testing the utility of characters derived from chitinous structures of the sting apparatus for elucidating relationships among the genera of Epiponini. The characters were obtained from the spiracular and quadrate plates, gonostylus, and sting. The data matrix was analyzed using parsimony with equal and implied weighting. Sting characters were also optimized on the tree of Wenzel & Carpenter (1994). Consensus of analysis using equal weights parsimony resulted in a tree with low resolution, but the use of implied weighting improved the results and a consensus tree with a better resolution was obtained. Implied weighting analysis showed an interesting result with Vespinae and Epiponini (the taxa that present the highest degree of sociality) together in a clade. The overall uniformity in morphology of sting apparatus and a possible influence of sociality on morphology could explain these results. The evolution of some characters is discussed.


Assuntos
Filogenia , Vespas , Animais , Evolução Biológica , Mordeduras e Picadas de Insetos
9.
Neotrop Entomol ; 42(3): 293-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23949812

RESUMO

The division of labor is a central theme in the study of social insects. In bees and wasps, this activity is regulated by age polyethism. Important physiological and morphological changes have been widely studied in the polyethism of honeybee workers. In contrast, this is a relatively unexplored subject in social vespids. Our goal was to determine if there are detectable morphological changes in the body of the Epiponini wasp Polybia paulista Von Ihering or in certain glands in relation to age polyethism. We observed changes in the body weight, the salivary gland, and the mandibular gland that were associated with age, and our results suggest that social relationships and task performance are important to these changes. This contrasts with observations in Polistes and is different from the Apis mellifera Linnaeus age polyethism model.


Assuntos
Vespas/anatomia & histologia , Vespas/crescimento & desenvolvimento , Fatores Etários , Animais , Feminino
10.
Scanning ; 23(3): 175-81, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11405302

RESUMO

Near-contact mode atomic force microscopy (AFM) imaging leads to sharper representations of DNA double strands on mica imaged at ambient conditions compared with noncontact mode AFM. Phase shift was used for feedback control yielding height information using a simple model calculation. No contact between tip and sample occurs. Measured DNA widths were up to four times smaller than measured with the same AFM tip in noncontact mode at ambient condition.


Assuntos
DNA/ultraestrutura , Microscopia de Força Atômica/métodos , Animais , Masculino , Salmão , Espermatozoides/química
11.
Biophys Chem ; 86(1): 29-35, 2000 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-11011697

RESUMO

In plant storage tissue, lipid bodies are composed of triacylglycerides and surrounded by a phospholipid monolayer which is stabilized by oleosins. At the onset of lipid body mobilization, cells express phospholipase A2, which partially degrades the monolayer and thus provides access for the subsequently acting triacylglyceride degrading enzymes. Analyzing the lipid body surface by atomic force microscopy we show that, at the stage of maximal phospholipase A2 expression, the monolayer contains holes of approximately 80 nm in width and 2.45 +/- 0.46 nm in depth. Non-contact mode imaging was performed with a lateral resolution of approximately 10 nm and a vertical resolution of less than 0.1 nm. The depth of the holes corresponds to the width of the monolayer, while the width of the channels is sufficiently large to provide access to 100 kDa enzymes, such as lipoxygenase and lipases.


Assuntos
Cucumis sativus/química , Fosfolipases A/química , Fosfolipídeos/química , Cucumis sativus/enzimologia , Eletroforese em Gel de Poliacrilamida , Glicerídeos/química , Membranas Artificiais , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Fosfolipases A2 , Sementes/química , Sementes/enzimologia , Propriedades de Superfície
12.
Scanning ; 22(1): 7-11, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10768383

RESUMO

In this paper we report that a combination of noncontact and contact atomic force microscopy is a convenient and reliable method for imaging and dissecting single plasmid deoxyribonucleic acid (DNA) strands on mica at ambient conditions without leaving feedback and without damage to the scanning tips. The width and thickness measured at different points of the DNA strands agree with literature data and are the same before and after dissection.


Assuntos
DNA/análise , Plasmídeos/análise , Microscopia de Força Atômica
13.
Urol Int ; 63(1): 32-9, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10592488

RESUMO

Treatment of superficial bladder carcinoma was derived by several large randomized trials. This group of cancers is stratified by differentiation grade and stage in three groups of different risk profiles (Ta G1-2 vs. T1 G1-2 vs. Tis/T1 G3). Standard therapy is fractionated transurethral resection (TUR). Adjuvant therapy after transurethral resection is not indicated in primary Ta G1-2 tumors because there is a low recurrence rate and no risk of tumor progression. The recurrence rate can be decreased up to 15% in recurrent Ta or T1 G1-2 tumors by intravesical therapy with mitomycin C (20 mg/instillation) or adriamycin (50 mg/instillation). Therapy should be limited to early (within 24 h post-TUR) and short-term treatment (4 x weekly, 5 x monthly). Alternatively, patients can be treated by intravesical BCG (strain Connaught or strain RIVM). Maintenance therapy is advantageous according to recurrence rate. Tumors with great malignant ability (Tis or T1 G3) will be treated initially with adjuvant BCG. Patients who fail are candidates for radical cystectomy within 3-6 months after initial diagnosis. There is no need - except in clinical trials - for the administration of unverified or not admitted drugs.


Assuntos
Carcinoma de Células de Transição/terapia , Neoplasias da Bexiga Urinária/terapia , Carcinoma de Células de Transição/mortalidade , Humanos , Recidiva Local de Neoplasia , Ensaios Clínicos Controlados Aleatórios como Assunto , Taxa de Sobrevida , Neoplasias da Bexiga Urinária/mortalidade
14.
Urology ; 54(3): 458-60, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10475354

RESUMO

OBJECTIVES: To ascertain the side effects of intravesical instillation of pertussis toxin (PTX) because it inhibits tumor cell motility in vitro and in vivo and seems to be a promising therapeutic approach against cancer. METHODS: We initiated a Phase I study and measured the effect of intravesical instillation of PTX before radical cystectomy. Study end points were PTX-related side effects. PTX was instilled at five dose levels, starting with 14 microg and continuing to 72 microg. RESULTS: Fifteen patients, with a median age of 64 years, were included in the study. Intravesical instillation of PTX was without local or systemic side effects (grade 0, according to National Cancer Institute toxicity criteria). CONCLUSIONS: Treatment with PTX was safe and well tolerated without any significant local or systemic toxicity in dosages up to 72 microg. Therefore, the influence of PTX on local tumor should be evaluated in a Phase II study.


Assuntos
Carcinoma de Células de Transição/terapia , Cistectomia , Toxina Pertussis , Neoplasias da Bexiga Urinária/terapia , Fatores de Virulência de Bordetella/administração & dosagem , Administração Intravesical , Idoso , Carcinoma de Células de Transição/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Estudos Prospectivos , Neoplasias da Bexiga Urinária/cirurgia
15.
Phys Rev B Condens Matter ; 54(7): 4913-4918, 1996 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-9986453
16.
Mol Cell Biochem ; 160-161: 289-95, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8901485

RESUMO

This review deals with glycogen phosphorylase (GP) and its isoenzyme BB in the diagnosis of ischaemic myocardial injury. Early identification and confirmation of acute myocardial infarction is essential for correct patient care and disposition decision in the emergency department. In this respect, glycogen phosphorylase isoenzyme BB (GPBB) based on its metabolic function is an enzyme for early laboratory detection of ischaemia. In the aerobic heart muscle GPBB together with glycogen is tightly associated with the vesicles of the sarcoplasmic reticulum. Release of GPBB, the main isoform in the human myocardium, essentially depends on the degradation of glycogen, which is catalyzed by GP. Ischaemia is known to favour the conversion of bound GP in the b form into GP a, thereby accelerating glycogen breakdown, which is the ultimate prerequisite for getting GP into a soluble form being able to move freely in the cytosol. The efflux of GPBB into the extracellular fluid follows if ischaemia-induced structural alterations in the cell membrane become manifest. The clinical application of GPBB as a marker of ischaemic myocardial injury is a very promising tool for extending our knowledge of the severity of myocardial ischaemic events in the various coronary syndromes. The rational roots of this development were originated from Albert Wollenberger's research work on the biochemistry of cardiac ischaemia and the transient acceleration of glycogenolysis mainly brought about by GP activation.


Assuntos
Isoenzimas/metabolismo , Miocárdio/metabolismo , Fosforilases/metabolismo , Anaerobiose , Ponte de Artéria Coronária , Creatina Quinase/metabolismo , Ativação Enzimática , Humanos , Cinética , Modelos Biológicos , Infarto do Miocárdio/enzimologia , Isquemia Miocárdica/fisiopatologia
17.
Clin Chem ; 41(7): 966-78, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7600699

RESUMO

With a new immunoenzymometric assay we measured human glycogen phosphorylase isoenzyme BB (GPBB) in 116 healthy individuals, 14 patients with stable angina, 107 nontraumatic chest pain patients on admission to the emergency department [45 acute myocardial infarction (AMI), 49 unstable angina, 13 other diseases], and in serial samples from 41 AMI patients. GPBB was compared with creatine kinase (CK), CKMB mass, myoglobin, and cardiac troponin T. Receiver-operating characteristic plots demonstrated the significantly greater (P < or = 0.012) discriminatory power of GPBB to detect acute ischemic coronary syndromes compared with all other tested markers. GPBB was the most sensitive marker for detection of AMI during the first 4 h after onset of chest pain, and only GPBB was increased above the upper reference limit (7 micrograms/L) on admission in patients who had unstable angina at rest and reversible ST-T alterations. This and the high early sensitivity of GPBB are most likely explained by its function as a key enzyme of glycogenolysis.


Assuntos
Ensaios Enzimáticos Clínicos , Técnicas Imunoenzimáticas , Isoenzimas/sangue , Infarto do Miocárdio/diagnóstico , Fosforilases/sangue , Adulto , Idoso , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , Creatina Quinase/sangue , Feminino , Humanos , Técnicas Imunoenzimáticas/estatística & dados numéricos , Cinética , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/enzimologia , Mioglobina/sangue , Valores de Referência , Sensibilidade e Especificidade , Troponina/sangue , Troponina T
18.
Neurourol Urodyn ; 14(4): 351-8, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7581471

RESUMO

Sphincterotomy was the treatment of choice in spinal cord injured patients with reflex bladder activity and detrusor sphincter dyssynergia after World War II. However, nowadays the conversion of a spastic bladder into a low pressure reservoir by medication or operatively has become a more favourable bladder management. Only in quadriplegic patients who are not able to perform self-catheterization, this treatment modality seemed to be an alternative. With twelve o'clock sphincterotomy, urodynamic parameters of the lower urinary tract can be brought to favourable measures (leak-point, residuals). However, the reoperation rate for the maintenance of these urodynamic results is high (57%). Laser sphincterotomy seems to be advantageous in this respect, as it reduces the need for resphincterotomy significantly. Additionally, 14% of the patients needed operations, which made condom fixation possible. Upper tract could only be preserved if sphincterotomy is done early enough. Patients who do not empty completely while in the wheelchair are at risk to develop a hydronephrosis.


Assuntos
Quadriplegia/complicações , Bexiga Urinaria Neurogênica/cirurgia , Adulto , Seguimentos , Humanos , Masculino , Complicações Pós-Operatórias/terapia , Reoperação , Traumatismos da Medula Espinal/complicações , Resultado do Tratamento , Bexiga Urinaria Neurogênica/etiologia , Bexiga Urinaria Neurogênica/fisiopatologia , Urodinâmica
19.
Br Heart J ; 72(2): 125-7, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7917682

RESUMO

OBJECTIVE: To determine whether transient ST-T alterations in patients with unstable angina are associated with an increase in plasma glycogen phosphorylase BB concentrations on admission to hospital. DESIGN: Prospective screening of patients with unstable angina for markers of myocardial cell damage. SETTING: Accident and emergency department of university hospital. PATIENTS: 48 consecutive patients admitted for angina pectoris (18 with transient ST-T alterations). None of the patients had acute myocardial infarction according to standard criteria. MAIN OUTCOME MEASURES: Creatine kinase and creatine kinase MB activities, creatine kinase MB mass concentration, and myoglobin, cardiac troponin T, and glycogen phosphorylase BB concentrations on admission. RESULTS: All variables except for creatine kinase and creatine kinase MB activities were significantly higher on admission in patients with unstable angina and transient ST-T alterations than in patients without. However, glycogen phosphorylase BB concentration was the only marker that was significantly (p = 0.0001) increased above its discriminator value in most patients (16). In the 18 patients with transient ST-T alterations creatine kinase MB mass concentration and troponin T and myoglobin concentrations were significantly (p = 0.0001) less commonly increased on admission (in five, three, and two patients, respectively). CONCLUSIONS: The early release of glycogen phosphorylase BB may help to identify high risk patients with unstable angina even on admission to an emergency department. Glycogen phosphorylase BB concentrations could help to guide decisions about patient management.


Assuntos
Angina Instável/enzimologia , Eletrocardiografia , Coração/fisiopatologia , Isoenzimas/metabolismo , Fosforilases/metabolismo , Angina Instável/fisiopatologia , Biomarcadores/sangue , Creatina Quinase/sangue , Feminino , Humanos , Isoenzimas/sangue , Masculino , Pessoa de Meia-Idade , Fosforilases/sangue , Estudos Prospectivos
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