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1.
Chemistry ; 29(5): e202202749, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36268910

RESUMO

The synthesis and the first structural characterization of the halogenated pyridinium salts [C5 F5 NH]+ , [C5 F4 ClNH]+ , [(C5 F5 N)2 H]+ , [(C5 Cl5 N)2 H]+ of the weakly coordinating anion (WCA) [Al(OTeF5 )4 ]- , showing noncovalent interactions in the solid state, are presented. The salts were characterized by the multinuclear NMR and IR spectroscopy as well as X-ray diffraction. Hirshfeld surface analysis and solid state structures reveal various intermolecular anion-π and σ-hole interactions between the corresponding halogenated pyridinium cations and the anion [Al(OTeF5 )4 ]- .


Assuntos
Sais , Ânions , Ressonância Magnética Nuclear Biomolecular , Difração de Raios X
2.
Angew Chem Int Ed Engl ; 59(37): 16002-16006, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32459871

RESUMO

A facile one-pot gram-scale synthesis of tetraalkylammonium tetrafluoridochlorate(III) [cat][ClF4 ] ([cat]=[NEt3 Me]+ , [NEt4 ]+ ) is described. An acetonitrile solution of the corresponding alkylammonium chloride salt is fluorinated with diluted fluorine at low temperatures. The reaction proceeds via the [ClF2 ]- anion which is structurally characterized for the first time. The potential application of [ClF4 ]- salts as fluorinating agents is evaluated by the reaction with diphenyl disulfide, Ph2 S2 , to pentafluorosulfanyl benzene, PhSF5 . The CN moieties in acetonitrile and [B(CN)4 ]- are transferred in CF3 groups. Exposure of carbon monoxide, CO, leads to the formation of carbonyl fluoride, COF2 , and elemental gold is dissolved under the formation of tetrafluoridoaurate [AuF4 ]- .

3.
Pneumologie ; 68(4): 266-9, 2014 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-24615667

RESUMO

Reduced pulmonary diffusion capacity is a hallmark of COPD, although the relative contribution of the subcomponents of pulmonary diffusion--membranous component (Dm) and capillary volume (Vc)--is unknown. These components can be measured with the method of NO single-breath diffusion (DLNO). In a prospective study, pulmonary function tests including spirometry, body plethysmography and single-breath measurements of diffusion capacity with CO and NO were performed in 183 patients with COPD of varying severity. There was a severity-dependent decrease in DLCO. Furthermore, Dm as well as Vc was positively correlated with the severity of COPD measured by FEV1. In all stages of COPD, reduction of Vc was more pronounced than constriction of Dm. In patients with most severe COPD, the preponderance of the reduction of Vc was significantly more marked than in milder stages.We conclude that Dm as well as Vc contributes to the reduction of DLCO in COPD, with a predominance of Vc at all stages of COPD. This confirms the idea that the loss of pulmonary capillaries in COPD is functionally relevant.


Assuntos
Volume Sanguíneo , Capilares/fisiopatologia , Pulmão/irrigação sanguínea , Pulmão/fisiopatologia , Capacidade de Difusão Pulmonar , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Idoso , Velocidade do Fluxo Sanguíneo , Determinação do Volume Sanguíneo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espirometria
4.
Int J Surg Case Rep ; 114: 109103, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38103319

RESUMO

INTRODUCTION: Treating advanced peripheral arterial occlusive disease (e.g. PAOD IV) poses a significant challenge, as conventional treatments quite often fall short at this stage. However, a range of interventions can be considered to postpone amputation. This study presents an example of advanced stage of Peripheral Artery Occlusive Disease (PAOD) stage IV, encompassing a history of a high thigh amputation on the left side, coupled with pronounced wound healing disorders. PRESENTATION OF CASE: Our patient, 55 years old, smoker and ASA Class III is in a left sided above-the knee-amputation situation. He presented to our outpatient clinic with blistering in the stump area, caused by non-proportinate pressure from the prosthesis. With an emerging septic course and advanced peripheral arterial occlusive disease (PAOD) at Fontaine class IV, revascularization was unfeasible in the left iliac artery axis and groin arteries. Additionally, a stage PAOD IV presents itself with poorly healing wounds on the right side which our patient still uses to support his transfers in and out bed and his wheelchair. Multiple surgical stump revisions and femur shortenings and diverse wound treatments were performed all were unsatisfying for patient and practitioners. We introduced a novel biochemisurgical treatment in our teaching hospital. DISCUSSION: Desiccating-agent-A is an innovative dehydrating agent with potent desiccating characteristics upon application to organic substances. Its formulation involves blending 83% methane sulfonic acid with proton acceptors and dimethyl sulfoxide, as outlined in patent application. The case description results in an illustrated follow up period of 16 months and is presented in line with the recommendations of the consensus-based surgical case reporting guideline development. CONCLUSION: The goal of achieving a secondary healing trend is to establish stability within the wound area or achieve complete healing. This endeavor becomes particularly intricate when severe blood circulation compromise exists. Nonetheless, progress in wound treatment measures has made it feasible to achieve this aim by fostering the formation of dry and clean necrotic tissue. This dry and clean wound is now manageable in a patient's home situation, allowing for effective care and a better chance at preventing further severe complications.

5.
Nanotechnology ; 24(36): 365702, 2013 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-23942355

RESUMO

Pairs of samples containing Ag nanoparticles (NPs) of different dimensions have been produced under the same conditions but on different substrates, namely standard glass slides and a thin layer of amorphous aluminum oxide (a-Al2O3) on-glass. Upon storage in ambient conditions (air and room temperature) the color of samples changed and a blue-shift and damping of the surface plasmon resonance was observed. The changes are weaker for the samples on-glass and tend to saturate after 12 months. In contrast, the changes for the samples on a-Al2O3 appear to be still progressing after 25 months. While x-ray photoelectron spectroscopy shows a slight sulfurization and negligible oxidation of the Ag for the on-glass samples upon 25 months aging, it shows that Ag is strongly oxidized for the on a-Al2O3 samples and sulfurization is negligible. Both optical and chemical results are consistent with the production of a shell at the expense of a reduction of the metal core dimensions, the latter being responsible for the blue-shift and related to the small (<10 nm initial diameter) of the NPs. The enhanced reactivity of the Ag NPs on the a-Al2O3 supports goes along with specific morphological changes of the Ag NPs and the observation of nitrogen.

6.
Infection ; 40(5): 537-41, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22802097

RESUMO

PURPOSE: Most cases of cellulitis are traditionally attributed to ß-hemolytic Streptococcus and Staphylococcus species, although in most cases, no organism is identified. Development of PCR using the conserved bacterial 16 S rRNA DNA permits identification of bacteria independent of conventional culture approaches and prior use of antibiotics. METHODS: We used PCR-based techniques to identify cellulitis etiology using aspirate samples from affected skin. Saline was infiltrated and aspirated at the site of greatest erythema or at the cellulitic border. Samples were tested for 16 S rRNA DNA, and organism-specific probes used to identify bacteria commonly seen in skin infections. RESULTS: Aspirates from 32 patients were studied, and 16 S rRNA DNA was detected in nine of these patient samples (28.1%). Bacterial species were identified by PCR methods in six of these nine samples (66.6%), with S. aureus and methicillin-resistant S. aureus (MRSA) identified in four and two, respectively, of these samples. Of the patients with positive aspirate bacterial cultures (3/9, 33.3%), S. aureus and coagulase-negative Staphylococcus (CoNS) were present on cultures of two of the three (both 66.6%) positive samples. Only in one of the three positive bacterial cultures did the PCR method detect the same organism as was detected by culture. Among patients with positive provider-collected clinical cultures, MRSA was the predominant organism (11/18, 61.1%) and when present, it was found as the sole organism. Where S. aureus or Streptococcus species were detected by molecular methods, clinical cultures yielded a positive result as well. CONCLUSIONS: PCR-based techniques do not appear to be more sensitive than aspirate cultures for the detection of pathogens in cellulitis.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Celulite (Flegmão)/microbiologia , Reação em Cadeia da Polimerase/métodos , Celulite (Flegmão)/diagnóstico , DNA Bacteriano/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , RNA Ribossômico 16S/genética , Sensibilidade e Especificidade , Dermatopatias Bacterianas/diagnóstico , Dermatopatias Bacterianas/microbiologia , Infecções dos Tecidos Moles/diagnóstico , Infecções dos Tecidos Moles/microbiologia , Staphylococcus aureus/classificação , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação
7.
Gesundheitswesen ; 74(11): 736-41, 2012 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-22012562

RESUMO

OBJECTIVES: The aim of this study was to understand the quantity and quality of psychosocial services offered at counselling centres for outpatients with cancer in Saxony, a federal state of Germany. METHODS: Structured interviews with employees on site at the counselling centres in Saxony (N=30) and an analysis of their yearly reports were undertaken. RESULTS: The majority of the counselling centres (N=25) was situated at local health departments. All institutions document their activities regularly and offer continuous training for their employees. Services include primarily information on and admission to social services whereas psychological and psychotherapeutic services are rare. Considering the guideline criteria for staffing with a ratio of one counsellor per 75,000 inhabitants, a total of 23 counsellors were lacking in the federal state of Saxony at the time of investigation. CONCLUSIONS: The method of situating counselling centres at local health departments ensures good access for almost all cancer patients and relatives seeking counselling. However, due to restricted financial resources the services offered are not sufficient according to the guidelines and solutions for this situation are needed.


Assuntos
Assistência Ambulatorial/estatística & dados numéricos , Aconselhamento Diretivo/provisão & distribuição , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Neoplasias/epidemiologia , Neoplasias/reabilitação , Pacientes Ambulatoriais/estatística & dados numéricos , Alemanha/epidemiologia , Humanos , Apoio Social
9.
Stud Health Technol Inform ; 158: 127-31, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20543412

RESUMO

This study uses experimental data acquired from adolescents with idiopathic scoliosis to assess their postural control during quiet standing before and after posterior spinal fusion. Statistically significant differences were seen when comparing the pre- and post-surgical measures of balance calculated from data for three different test conditions.


Assuntos
Equilíbrio Postural/fisiologia , Escoliose/cirurgia , Fusão Vertebral , Adolescente , Feminino , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde
11.
Chem Commun (Camb) ; 53(96): 12958-12961, 2017 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-29160313

RESUMO

Here we discuss the reaction products of laser ablated alkali chlorides and elemental chlorine. Salt ablation using this technique combined with matrix-isolation spectroscopy allows for the formation and characterization of novel anionic species. The laser ablation of solid MCl with M = Cs, Rb, and K in the presence of Cl2 produced free [Cl3]- ions which were isolated in solid noble-gas matrices. For M = Cs, Rb, K, and Na, the ion pairs M+[Cl3]- are the main reaction products. Trends in the formation and bonding of these trichloride anions will be discussed. In contrast to the trifluoride analogues, the isolated ion pairs M+[Cl3]- feature a systematic distortion due to metal coordination.

12.
Artigo em Inglês | MEDLINE | ID: mdl-27269712

RESUMO

Differential sensitivity of primary hepatocytes and Chang cells to the cancer promoter fumonisin B1 (FB1)-induced cytotoxic effects were investigated in relation to changes in membrane lipid distribution. In contrast to primary hepatocytes, Chang cells were resistant to FB1-induced cytotoxic effects. This was associated with a high cholesterol (Chol) and sphingomyelin (SM) and low phosphatidylcholine (PC) content, resulting in a significant (P<0.05) decrease in phosphatidylethanolamine (PE)/PC ratio, increased Chol/total phosphoglyceride (TPG) ratios and low total polyunsaturated fatty acids (PUFA) content in PC and PE, suggesting a more rigid membrane structure. High levels of C18:1 and reduced polyunsaturated fatty acid (PUFA) levels are likely to provide selective resistance to FB1-induced oxidative stress. FB1-associated lipid changes included decreases in SM and Chol, increases in sphinganine (Sa) and PE with the increases in key saturated, monounsaturated, and PUFAs in PE as key role players in the differential responses to FB1-induced cell growth responses in cells.


Assuntos
Resistência a Medicamentos , Fumonisinas/farmacologia , Hepatócitos/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Ácidos Graxos Insaturados/metabolismo , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Técnicas In Vitro , Lipídeos de Membrana/análise , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas/metabolismo , Ratos
13.
J Agric Saf Health ; 22(1): 13-32, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27024990

RESUMO

This article summarizes data gathered on 246 documented cases of children and youth under the age of 21 involved in grain storage and handling incidents in agricultural workplaces from 1964 to 2013 in the U.S. that have been entered into the Purdue Agricultural Confined Space Incident Database. The database is the result of ongoing efforts to collect and file information on documented injuries, fatalities, and entrapments in all forms of agricultural confined spaces. While the frequency of injuries and fatalities involving children and youth in agriculture has decreased in recent years, incidents related to agricultural confined spaces, especially grain storage and handling facilities, have remained largely unchanged during the same period. Approximately 21% of all documented incidents involved children and youth (age 20 and younger), and more than 77% of all documented incidents were fatal, suggesting an under-reporting of non-fatal incidents. Findings indicate that the majority of youth incidents occurred at OSHA exempt agricultural worksites. The states reporting the most incidents were Indiana, Iowa, Nebraska, Illinois, and Minnesota. Grain transport vehicles represented a significant portion of incidents involving children under the age of 16. The overwhelming majority of victims were male, and most incidents (50%) occurred in June, October, and November. Recommendations include developing intervention strategies that target OSHA exempt farms, feedlots, and seed processing facilities; preparing engineering design and best practice standards that reduce the exposure of children and youth to agricultural confined spaces; and developing gender-specific safety resources that incorporate gender-sensitive strategies to communicate safety information to the population of young males with the greatest risk of exposure to the hazards of agricultural confined spaces.


Assuntos
Acidentes de Trabalho/estatística & dados numéricos , Agricultura , Adolescente , Distribuição por Idade , Agricultura/estatística & dados numéricos , Criança , Pré-Escolar , Espaços Confinados , Bases de Dados Factuais , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estados Unidos , Adulto Jovem
14.
Biochim Biophys Acta ; 557(1): 179-87, 1979 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-549635

RESUMO

Octyl beta-D-glucoside was synthetized from alpha-acetobromoglucose with an improved method yielding a very pure product with a sharp melting point (108-109 degrees C) and free of intermediate products as judged by IR and NMR spectra. The yield of the synthesis is 66% when referred to alpha-acetobromoglucose. The potency of this compound as a detergent on hog kidney brush border membranes was compared to the action of Triton X-100. Octyl glucoside preferentially extracts aminopeptidase M and gamma-glutamyltranspeptidase in a concentration-dependent manner. The more deeply imbedded membrane enzyme, alkaline phosphatase, was relatively resistent to the action of octyl glucoside. In contrast, Triton X-100 extracted all membrane proteins to about the same extent. Additionally it was found that octyl glucoside can be removed from membrane extracts by Biobead SM 2. The capacity of the beads is about 170 mg detergent/g of dry Biobead SM 2. Thus octyl glucoside seems to be a useful tool for solubilization and purification of brush border membranes proteins.


Assuntos
Membrana Celular/análise , Detergentes , Rim/análise , Proteínas de Membrana/isolamento & purificação , Microvilosidades/análise , Animais , Detergentes/síntese química , Glucosídeos/síntese química , Polietilenoglicóis , Ligação Proteica , Solubilidade , Suínos
15.
Biochim Biophys Acta ; 640(1): 43-54, 1981 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-7194113

RESUMO

A brush border membrane fraction isolated from hog kidney cortex was solubilized with 0.5% Triton X-100 and subjected to affinity chromatography on a phlorizin polymer. As demonstrated by transport studies with reconstituted proteoliposomes, the polymer adsorbs the sodium-dependent D-glucose transport system. The latter can be eluted from the polymer by 0.5 M D-glucose. The purified fraction contains 0.4% of the membrane protein extract and exhibits a 20--30-fold higher transport activity than the crude membrane extract. Other brush border membrane proteins such as alkaline phosphatase and aminopeptidase M are markedly reduced in the purified fraction. Thus, affinity chromatography on a phlorizin polymer is a suitable tool for the isolation of the sodium-glucose transport system present in brush border membranes.


Assuntos
Glucose/metabolismo , Córtex Renal/metabolismo , Sódio/metabolismo , Animais , Transporte Biológico , Proteínas de Transporte/metabolismo , Cromatografia de Afinidade , Cinética , Lipossomos , Microvilosidades/metabolismo , Peso Molecular , Proteínas de Transporte de Monossacarídeos , Monossacarídeos/metabolismo , Florizina , Suínos
16.
Food Chem Toxicol ; 78: 96-104, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25656646

RESUMO

Changes in lipid metabolism have been associated with tumor promotion in rat liver. Similarities and differences of lipid parameters were investigated using the mycotoxin fumonisin B1 (FB1) and the 2-acetylaminofluorene/partial hepatectomy (AAF/PH) treatments as cancer promoters in rat liver. A typical lipid phenotype was observed, including increased membranal phosphatidylethanolamine (PE) and cholesterol content, increased levels of C16:0 and monounsaturated fatty acids in PE and phosphatidylcholine (PC), as well as a decrease in C18:0 and long-chained polyunsaturated fatty acids in the PC fraction. The observed lipid changes, which likely resulted in changes in membrane structure and fluidity, may represent a growth stimulus exerted by the cancer promoters that could provide initiated cells with a selective growth advantage. This study provided insight into complex lipid profiles induced by two different cancer promoting treatments and their potential role in the development of hepatocyte nodules, which can be used to identify targets for the development of chemopreventive strategies against cancer promotion in the liver.


Assuntos
2-Acetilaminofluoreno/administração & dosagem , Fumonisinas/administração & dosagem , Metabolismo dos Lipídeos/efeitos dos fármacos , Neoplasias Hepáticas Experimentais/metabolismo , Fenótipo , 2-Acetilaminofluoreno/toxicidade , Animais , Colesterol/metabolismo , Ácidos Graxos , Ácidos Graxos Monoinsaturados/metabolismo , Ácidos Graxos Insaturados/metabolismo , Fumonisinas/toxicidade , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Fígado/metabolismo , Neoplasias Hepáticas Experimentais/induzido quimicamente , Masculino , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas/metabolismo , Ratos , Ratos Endogâmicos F344
17.
J Cataract Refract Surg ; 19 Suppl: 136-43, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8450435

RESUMO

A major advantage of myopic photorefractive keratectomy (PRK) is the precision with which the excimer laser ablates corneal tissue. But like other refractive surgery procedures, PRK must solve the problem of accurately centering the treatment zone. We present our technique for PRK centration with postoperative corneal topographic data on 110 patients from Phase IIB and III of the clinical trials. The distance between the center of the post-PRK flat zone and the corneal vertex was determined by topography in millimeters and meridian degrees. On average, treatment zones were decentered down and right 0.52 mm at 196.74 degrees; 92.73% were centered within 1.00 mm, while 57.27% were within 0.50 mm. The centration data were correlated to postoperative visual acuity as well as treatment zone diameter. Mean uncorrected visual acuity was 20/20 for decentrations up to 1.00 mm but fell to 20/30 for deviations greater than 1.00 mm. Best corrected acuity was also preserved below 1.00 mm but compromised above this level. No difference in decentration was found between 4.5 mm and 5.0 mm ablation zones. Our findings indicate that PRK centration is accurate within 1.0 mm in over 92% of cases and that visual acuity is relatively preserved despite deviations from perfect centration. Further technical improvements will enhance the accuracy of PRK.


Assuntos
Córnea/anatomia & histologia , Terapia a Laser/métodos , Miopia/cirurgia , Adulto , Idoso , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Pupila , Estudos Retrospectivos , Acuidade Visual
18.
J Cataract Refract Surg ; 19 Suppl: 144-8, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8450436

RESUMO

The centration of excimer laser photorefractive keratectomy (PRK) is critical to the procedure's success. We evaluated PRK centration in 49 patients using the EyeSys topography system. Ablation zone centration was measured from the corneal vertex and from the pupillary center using the pupil-finding software. Centration was measured more accurately from the pupillary center (0.40 mm) than from the corneal vertex (0.44 mm). Right eyes were decentered less than left eyes. There was an unpredictable correlation between amount of decentration and postoperative visual acuities. The ability to measure centration of keratorefractive procedures precisely from the pupil is an important advance in topography technology.


Assuntos
Córnea/cirurgia , Terapia a Laser/métodos , Miopia/cirurgia , Pupila , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Acuidade Visual
19.
J Gerontol B Psychol Sci Soc Sci ; 53(3): P165-74, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9602832

RESUMO

The associations between self-reported rewards and difficulties of caregiving and burden were examined in a sample of 200 informal caregivers to older post-rehabilitation patients. Sixteen percent (16%) of caregivers reported that caregiving was physically difficult only, 15% reported emotional difficulties only, 11% reported social difficulties only, 17% reported multiple difficulties, and 40% had no difficulties. Each type of difficulty (e.g., social, emotional, and physical) was significantly associated with burden in univariate and multiple linear regression analyses, controlling for confounding characteristics. Caregivers reporting multiple types of difficulty experienced higher levels of burden than caregivers who reported only one type of difficulty. Caregivers who received more rewards from caregiving reported fewer difficulties. Caregiving rewards had no independent effect on burden but modified the associations between social and emotional difficulties and burden. In summary, caregiving rewards and difficulties were not mutually exclusive, and their relationship in turn affected burden.


Assuntos
Cuidadores/psicologia , Motivação , Qualidade de Vida , Afeto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reabilitação , Recompensa , Apoio Social , Inquéritos e Questionários
20.
Artigo em Inglês | MEDLINE | ID: mdl-18263164

RESUMO

The temperature dependence of acoustic plate mode (APM) devices used as probes for dilute electrolytes is described. Specifically, the probe responses that consist of the frequency change and device loss were studied for dilute aqueous solutions of alkali metal ions. It is shown that by integrating the temperature dependence of the APM probe responses with pattern recognition techniques, valuable information about the solutions can be obtained that include identification and quantification. A preliminary investigation of the feasibility of identifying binary mixtures of the alkali metal ion solutions using only the temperature responses showed good results.

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