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1.
J Am Chem Soc ; 145(49): 26993-27009, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38032858

RESUMO

Molybdenum alkylidynes endowed with tripodal silanolate ligands belong to the most active and selective catalysts for alkyne metathesis known to date. This paper describes a new generation that is distinguished by an unprecedented level of stability and practicality without sacrificing the chemical virtues of their predecessors. Specifically, pyridine adducts of type 16 are easy to make on gram scale, can be routinely weighed and handled in air, and stay intact for many months outside the glovebox. When dissolved in toluene, however, spontaneous dissociation of the stabilizing pyridine ligand releases an active species of excellent performance and functional group tolerance. Specifically, a host of polar and apolar groups, various protic sites, and numerous basic functionalities proved compatible. The catalysts are characterized by crystallographic and spectroscopic means, including 95Mo NMR; their activity and stability are benchmarked in detail, and the enabling properties are illustrated by advanced applications to natural product synthesis. For the favorable overall application profile and ease of handling, complexes of this new series are expected to replace earlier catalyst generations and help encourage a more regular use of alkyne metathesis in general.

2.
Chemistry ; 27(56): 14025-14033, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34293239

RESUMO

Molybdenum alkylidyne complexes with a trisilanolate podand ligand framework ("canopy catalysts") are the arguably most selective catalysts for alkyne metathesis known to date. Among them, complex 1 a endowed with a fence of lateral methyl substituents on the silicon linkers is the most reactive, although fairly high loadings are required in certain applications. It is now shown that this catalyst decomposes readily via a bimolecular pathway that engages the Mo≡CR entities in a stoichiometric triple-bond metathesis event to furnish RC≡CR and the corresponding dinuclear complex, 8, with a Mo≡Mo core. In addition to the regular analytical techniques, 95 Mo NMR was used to confirm this unusual outcome. This rapid degradation mechanism is largely avoided by increasing the size of the peripheral substituents on silicon, without unduly compromising the activity of the resulting complexes. When chemically challenged, however, canopy catalysts can open the apparently somewhat strained tripodal ligand cages; this reorganization leads to the formation of cyclo-tetrameric arrays composed of four metal alkylidyne units linked together via one silanol arm of the ligand backbone. The analogous tungsten alkylidyne complex 6, endowed with a tripodal tris-alkoxide (rather than siloxide) ligand framework, is even more susceptible to such a controlled and reversible cyclo-oligomerization. The structures of the resulting giant macrocyclic ensembles were established by single-crystal X-ray diffraction.


Assuntos
Alcinos , Alcinos/química , Catálise , Compostos Organometálicos/síntese química , Compostos Organometálicos/química
3.
Angew Chem Int Ed Engl ; 59(12): 4888-4891, 2020 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-31912609

RESUMO

The gold(I)-catalyzed reaction of acetylene gas with alkenes leads to (Z,Z)-1,4-disubstituted 1,3-butadienes and biscyclopropanes depending on the donor ligand on gold(I). Acetylene was generated in situ from calcium carbide and water in a user-friendly procedure. Reaction of acetylene with 1,5-dienes gives rise stereoselectively to tricyclo[5.1.0.02,4 ]octanes. This novel double cyclopropanation has been applied to the one step total synthesis of the natural product waitziacuminone from acetylene and geranyl acetone.

6.
Z Gastroenterol ; 51(11): 1269-326, 2013 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-24243572

RESUMO

The interdisciplinary guidelines at the S3 level on the diagnosis of and therapy for hepatocellular carcinoma (HCC) constitute an evidence- and consensus-based instrument that is aimed at improving the diagnosis of and therapy for HCC since these are very challenging tasks. The purpose of the guidelines is to offer the patient (with suspected or confirmed HCC) adequate, scientifically based and up-to-date procedures in diagnosis, therapy and rehabilitation. This holds not only for locally limited or focally advanced disease but also for the existence of recurrences or distant metastases. Besides making a contribution to an appropriate health-care service, the guidelines should also provide the foundation for an individually adapted, high-quality therapy. The explanatory background texts should also enable non-specialist but responsible colleagues to give sound advice to their patients concerning specialist procedures, side effects and results. In the medium and long-term this should reduce the morbidity and mortality of patients with HCC and improve their quality of life.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/terapia , Oncologia/normas , Guias de Prática Clínica como Assunto , Alemanha , Humanos
8.
Rehabilitation (Stuttg) ; 49(2): 95-104, 2010 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-20446192

RESUMO

The present study investigated whether women and men differ with regard to non-religious and religious coping with cancer, here: colon cancer--a question on which only little research has been done so far. 341 patients filled in a questionnaire during inpatient oncological rehabilitation. Statistical analyses showed that women reported higher mental strain than men. They used more bagatellization and wishful thinking, more depressive and less active problem-oriented coping strategies. A higher use of religious coping among women was to a high degree associated with their generally stronger religiosity. Correlations between coping strategies and measures of mental health indicated commonalities and differences. In particular, a positive correlation between active problem-oriented coping and mental health was found for men but not for women. In accordance with women's higher religiosity, the data indicate a stronger correlation between religious coping and adaptation among women than among men. The results suggest that gender differences and religiosity can be relevant in the context of treatment but that their significance must not be overinterpreted. In terms of patient orientation they speak for the necessity to individually assess the need for support, also with regard to the consideration of religiosity in the treatment process.


Assuntos
Adaptação Psicológica , Neoplasias do Colo/psicologia , Identidade de Gênero , Religião e Medicina , Religião e Psicologia , Idoso , Feminino , Alemanha , Humanos , Comportamento de Doença , Masculino , Pessoa de Meia-Idade , Admissão do Paciente , Resolução de Problemas , Inquéritos e Questionários
9.
Eur J Cancer Care (Engl) ; 17(4): 361-70, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18652003

RESUMO

Within the last few years the relationship between religiousness and psychosocial adjustment has become a subject of increasing interest. However, previous research did not explicitly differentiate between dispositional religious commitment and situation-specific religious coping. The current cross-sectional study investigated the relative power of religious commitment, positive and negative religious coping, and religious commitment x religious coping interactions in the prediction of anxiety. The sample consisted of 167 German breast cancer patients who were assessed during an inpatient rehabilitation programme. Results indicated that positive and negative religious coping were more strongly related to anxiety than dispositional religious commitment. Furthermore, hierarchical regression analysis revealed a religious commitment x negative religious coping interaction. According to this interaction, there seems to be some synergistic effect of high levels of religious commitment and high levels of negative religious coping. In contrast, positive religious coping did not function as a moderator and appeared to be closely related to religious commitment. This may be due to the specific religious-cultural background in Germany.


Assuntos
Adaptação Psicológica , Ansiedade/psicologia , Neoplasias da Mama/psicologia , Religião e Psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Atitude Frente a Saúde , Neoplasias da Mama/reabilitação , Estudos Transversais , Feminino , Alemanha , Humanos , Acontecimentos que Mudam a Vida , Pessoa de Meia-Idade , Análise de Regressão , Inquéritos e Questionários
11.
Eur J Clin Nutr ; 53(9): 740-5, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10509772

RESUMO

OBJECTIVE: Cachexia and weight loss are frequently seen in cancer patients. We investigated lipid metabolism to elucidate a metabolic basis for adequate nutrition of cancer patients. DESIGN: Lipid metabolism was assessed by indirect calorimetry and triglyceride clearance rates after randomised injection of a lipid bolus (long-chain triglycerides (LCT) or medium-chain triglycerides (MCT) during an euglycemic clamp protocol in cancer patients. SETTING: Rudolf-Virchow Krankenhaus, Berlin, Germany. SUBJECTS: Eighteen patients were included. Twelve patients had upper gastrointestinal cancer: a weight stable cancer group (Caws, n = 6) with a body mass index (BMI) of 22.9 +/- 1.7 kg/m2 and a weight losing cancer group (Cawl, n = 6) with a mean weight loss of 7.4 +/- 3.1 kg or 11% of the initial body weight during the previous three months (present BMI 21.8 +/- 0.8 kg/m2). The data were compared with six control patients with benign gastrointestinal diseases (BMI = 25.0 +/- 0.8 kg/m2). MAIN OUTCOME: Cancer patients had an increased basal lipid oxidation rate that was more pronounced in Cawl (+92% vs +42% in Caws; P < 0.01 and 0.05 vs controls, respectively). Utilisation of LCT was increased in cancer patients, this was most pronounced in Cawl (+150 vs +65% in Caws; P < 0.01 and 0.05, respectively). Metabolically, there were no differences in the utilisation of LCT and MCT/LCT containing lipid emulsions. CONCLUSIONS: Cancer patients have an increased lipid oxidation and an enhanced utilisation of exogeneous lipids. This is most pronounced in Cawl. To prevent further weight loss or to increase body weight, they should increase their fat intake. In contrast, fat-reduced or prudent diets seem to be inadequate for the nutrition of cancer patients.


Assuntos
Caquexia/metabolismo , Neoplasias Gastrointestinais/metabolismo , Metabolismo dos Lipídeos , Área Sob a Curva , Composição Corporal , Peso Corporal , Calorimetria Indireta , Ácidos Graxos não Esterificados/sangue , Feminino , Neoplasias Gastrointestinais/fisiopatologia , Técnica Clamp de Glucose , Meia-Vida , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Triglicerídeos/farmacologia , Redução de Peso
12.
Psychiatry Res ; 41(3): 227-35, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1594709

RESUMO

Attentional factors are thought to affect eye-tracking patterns. The present study examined the hypothesis that specific quantitative features of eye tracking would be correlated with the amplitude of a component of the auditory evoked potential, the N100, which is known to be enhanced by arousal and selective attention. We studied 12 clinically stable schizophrenic patients by means of DC-electro-oculography. The frequency and amplitude of different types of saccades (catchup, backup, anticipatory saccades, and square wave jerks) were assessed. The results suggest that small and large saccades, as classified by a simple amplitude criterion (4 degrees), have differential meanings and indicate that enhanced amplitudes of small saccades are an effect of arousal.


Assuntos
Nível de Alerta/fisiologia , Atenção/fisiologia , Eletroencefalografia , Potenciais Evocados Auditivos/fisiologia , Acompanhamento Ocular Uniforme/fisiologia , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Adulto , Idoso , Córtex Cerebral/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Reação/fisiologia , Movimentos Sacádicos/fisiologia , Esquizofrenia/diagnóstico
13.
Toxicol In Vitro ; 12(4): 353-64, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20654417

RESUMO

We report investigations into the potential of the steroid hormones chlormadinone acetate (CMA), cyproterone acetate (CPA), dexamethasone (DEX), estradiol (E(2)), ethinylestradiol (EE(2)), gestodene (GEST), levonorgestrel (LNG), megestrol acetate (MGA), medroxy progesterone acetate (MPA), mifepristone (MIFE), norethisterone (NET), prednisolone (PRED), progesterone (P) and testosterone (T) to form DNA adducts in precision-cut human liver slices in vitro from 14 male and female donors using the (32)P-postlabelling technique. The synthetic steroid hormones CPA, CMA and MGA generated DNA adducts in human liver slices obtained from all donors. MPA-related adduct spots were only observed in some of the livers tested. No DNA adduct formation was detectable with DEX, EE(2), E(2), GEST, LNG, MIFE, NET, PRED, P and T. The total DNA adduct levels and adduct patterns were different for each compound. On average, total DNA adduct levels decreased in the following order: CPA>MGA>CMAMPA. The DNA adduct levels varied inter-individually. At a treatment concentration of 1mug/ml, the coefficient of variation of the total adduct levels ranged from 38% to 101%. A sex-specific distribution of the DNA adduct formation was only detected after incubation with MPA. MPA-related adduct spots were observed predominantly in the livers of female donors.

15.
Med J Aust ; 140(2): 70-2, 1984 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-6694582

RESUMO

In our medically aware and litigation-conscious society, X-ray films of the lumbar spine are taken in many individuals. We have examined 1172 lumbar-spin X-ray films of young, healthy, predominantly male adults who were seeking employment. Abnormalities worthy of mention were found in 683 of these. These findings suggest that a correlation with the clinical condition of the patient should be carefully established before an abnormality found on an X-ray film is regarded as significant.


Assuntos
Vértebras Lombares/diagnóstico por imagem , Anormalidades Múltiplas , Adolescente , Adulto , Feminino , Humanos , Disco Intervertebral/anormalidades , Disco Intervertebral/diagnóstico por imagem , Vértebras Lombares/anormalidades , Masculino , Radiografia , Escoliose/diagnóstico por imagem , Espondilolistese/diagnóstico por imagem , Espondilólise/diagnóstico por imagem
16.
Hautarzt ; 52(12): 1107-10, 2001 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-11910863

RESUMO

The Muir-Torre syndrome (MTS) is a rare, autosomal-dominant inherited disease characterized by sebaceous gland tumors and at least one internal malignancy. In many cases a genetic defect known as microsatellite instability can be identified. Similar pathogenetic mechanisms are found in patients with the hereditary non-polyposis colon cancer syndrome, so that at least some patients with MTS are considered as having a phenotypic variant of that syndrome. A 66-year-old woman with MTS, developed multiple malignant cutaneous and visceral tumors over 32 years; in addition, she had multiple sebaceous gland adenomas. Microsatellite instability could be proved with 2 out of 5 studied markers. The family history was positive as numerous relatives of the patient's mother were reported to have developed internal malignancies.


Assuntos
Adenoma/genética , Carcinoma/genética , Neoplasias Primárias Múltiplas/genética , Síndromes Neoplásicas Hereditárias/genética , Neoplasias das Glândulas Sebáceas/genética , Adenoma/diagnóstico , Idoso , Carcinoma/diagnóstico , Aberrações Cromossômicas , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Neoplasias Colorretais Hereditárias sem Polipose/genética , Feminino , Genes Dominantes , Humanos , Neoplasias Primárias Múltiplas/diagnóstico , Síndromes Neoplásicas Hereditárias/diagnóstico , Linhagem , Neoplasias das Glândulas Sebáceas/diagnóstico
17.
Scand J Gastroenterol ; 33(10): 1113-7, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9829369

RESUMO

BACKGROUND: Crohn's disease (CD) represents a chronic inflammatory bowel disease with abnormal CD8 T-cell function in a subgroup of patients. METHODS: A 55-year-old woman presented with CD on the basis of clinical, endoscopic, radiologic, histologic, and sonographic examination. Since the disease could not be controlled with conventional anti-inflammatory therapy, a detailed analysis of cellular and humoral immune functions was performed and showed a dysbalanced T-cell activation pattern with an inverse CD4/CD8 ratio due to an increased number of CD8 T cells. Additionally, high IgM and low IgG2 antibody levels were detected. Treatment with intravenous immunoglobulin (IVIG) was started as immunomodulatory therapy. During this therapy the condition improved markedly. CD8 T-cell levels returned to normal, and IgM decreased as well. CONCLUSION: This case shows that selected cases of CD may be associated with abnormal functions and that such patients may benefit from IVIG treatment.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Doença de Crohn/imunologia , Doença de Crohn/terapia , Imunoglobulinas Intravenosas/uso terapêutico , Relação CD4-CD8 , Feminino , Humanos , Ativação Linfocitária , Pessoa de Meia-Idade
18.
Dtsch Med Wochenschr ; 122(30): 926-9, 1997 Jul 25.
Artigo em Alemão | MEDLINE | ID: mdl-9280705

RESUMO

HISTORY AND CLINICAL FINDINGS: A 25-year-old woman had for 5 years complained of lower and mid-abdominal pain, at first monthly but later continuous and gradually increasing in severity. At the same time she had diarrhoea associated with nausea, vomiting and weight loss. Physical examination showed a markedly distended abdomen, diffuse pain on pressure over the whole abdomen, most marked in the left middle and lower part, and high pitched peristalsis, but was otherwise unremarkable. INVESTIGATIONS: Abdominal radiography indicated small-intestinal ileus, while ultrasound revealed absent peristalsis in the small intestine and a 10 cm stenosis in the terminal ileum. Coloscopy demonstrated a fibrosed stenosis of the terminal ileum but a biopsy showed no specific changes. TREATMENT AND COURSE: Under suspicion of Crohn's disease with stenosis of the terminal ileum a partial resection of the ileum was performed. The ileum was on inspection thickened with scar tissue but no inflammation. Histology revealed florid chronic mucosal and submucosal inflammation, haemorrhages and ulcers, as well as numerous islands of endometriosis in the subserosa and muscularis propria. CONCLUSION: Endometriosis is a rare disease in women of the reproductive age, but should be considered in the differential diagnosis of Crohn's disease of the terminal ileum.


Assuntos
Doença de Crohn/diagnóstico , Endometriose/diagnóstico , Doenças do Íleo/diagnóstico , Adulto , Biópsia , Doença Crônica , Colonoscopia , Constrição Patológica/diagnóstico , Constrição Patológica/patologia , Constrição Patológica/cirurgia , Doença de Crohn/patologia , Doença de Crohn/cirurgia , Diagnóstico Diferencial , Endometriose/patologia , Endometriose/cirurgia , Feminino , Humanos , Doenças do Íleo/patologia , Doenças do Íleo/cirurgia , Íleo/diagnóstico por imagem , Íleo/patologia , Íleo/cirurgia , Radiografia , Ultrassonografia
19.
Psychother Psychosom ; 54(2-3): 110-6, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2098773

RESUMO

The term 'quality of life' is defined as the result of objective circumstances of life and subjective perceptions of patients. Health-related quality of life is a dynamic concept which changes during an adaptational process interacting with illness condition during the course of chronic inflammatory bowel disease. In a review on the research in this field, it is shown that quality-of-life assessment may be an important adjunct to the evaluation and treatment of patients with inflammatory bowel disease. The comparative evaluation of quality of life in patients treated medically and surgically may offer important information for decision making.


Assuntos
Doenças Inflamatórias Intestinais/psicologia , Transtornos Psicofisiológicos/psicologia , Qualidade de Vida , Papel do Doente , Humanos , Ileostomia/psicologia , Doenças Inflamatórias Intestinais/cirurgia , Ajustamento Social
20.
Unfallchirurg ; 106(11): 929-34, 2003 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-14634736

RESUMO

After experimental and preclinical evaluation (HAP Paul Award 2001) of the CT-free image-guided surgical navigation system for acetabular cup placement (SurgiGATE C-arm cup" by Medivision, Switzerland), the system was introduced into clinical routine. The computation of the angular orientation of the cup is based on reference coordinates from the anterior pelvic plane concept. A hybrid strategy for pelvic landmark acquisition has been introduced involving percutaneous pointer-based digitization with the noninvasive biplanar landmark reconstruction using multiple registered fluoroscopy images. From January 2001 to December 2002, a total of 256 consecutive patients with primary osteoarthrosis (mean age 69 years, 161 male, 95 female, 132 left, and 124 right hip joints) were operated on with the hybrid CT-free navigation system. During each operation the angular orientation of the inserted implant was recorded. To determine the placement accuracy of the acetabular components, 50 consecutive patients underwent a CT scan 7-10 days postoperatively to analyze the cup position related to the anterior pelvic plane. This was all done blinded by the same investigator with the planning software of the CT-based navigation system of Medivision. There was no significant learning curve observed for the use of the system. The mean value for postoperative inclination was 43 degrees (SD 3.0, range: 37 degrees -49 degrees ) and for anteversion 19 degrees (SD 3.9, range: 10 degrees -28 degrees ). The resulting system accuracy, i.e., the difference between intraoperatively calculated cup orientation and postoperatively measured implant position showed a mean error of 1.5 degrees for the inclination (maximum 5 degrees, SD 1.1) and 2.4 degrees for the anteversion (maximum 6 degrees, SD 1.3). An accuracy of better than 5 degrees inclination and 6 degrees anteversion was achieved under clinical conditions, which implies that there is no significant difference in performance from the established CT-based navigation methods. Image-guided CT-free cup navigation provides a reliable solution for future THA.


Assuntos
Acetábulo/cirurgia , Artroplastia de Quadril/instrumentação , Fluoroscopia/instrumentação , Processamento de Imagem Assistida por Computador/instrumentação , Imageamento Tridimensional/instrumentação , Osteoartrite do Quadril/cirurgia , Cirurgia Assistida por Computador/instrumentação , Tomografia Computadorizada Espiral/instrumentação , Acetábulo/diagnóstico por imagem , Idoso , Coleta de Dados/instrumentação , Desenho de Equipamento , Feminino , Humanos , Masculino , Computação Matemática , Osteoartrite do Quadril/diagnóstico por imagem , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Complicações Pós-Operatórias/diagnóstico por imagem , Reprodutibilidade dos Testes , Avaliação da Tecnologia Biomédica/estatística & dados numéricos
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