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1.
Tech Coloproctol ; 21(8): 595-604, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28795243

RESUMO

BACKGROUND: Until recently there has been little data available about long-term outcomes of laparoscopic rectal cancer surgery. But new randomized controlled trials regarding laparoscopic colorectal surgery have been published. The aim of this study was to compare the short- and long-term oncologic outcomes of laparoscopy and open surgery for rectal cancer through a systematic review of the literature and a meta-analysis of relevant RCTs. METHODS: A systematic review of Medline, Embase and the Cochrane library from January 1966 to October 2016 with a subsequent meta-analysis was performed. Only randomized controlled trials with data on circumferential resection margins were included. The primary outcome was the status of circumferential resection margins. Secondary outcomes included lymph node yield, distal resection margins, disease-free and overall survival rates for 3 and 5 years and local recurrence rates. RESULTS: Eleven studies were evaluated, involving a total of 2018 patients in the laparoscopic group and 1526 patients in the open group. The presence of involved circumferential margins was reported in all studies. There were no statistically significant differences in the number of positive circumferential margins between the laparoscopic group and open group, RR 1.16, 95% CI 0.89-1.50 and no significant differences in involvement of distal margins (RR 1.13 95% CI 0.35-3.66), completeness of mesorectal excision (RR 1.22, 95% CI 0.82-1.82) or number of harvested lymph nodes (mean difference = -0.01, 95% CI -0.89 to 0.87). Disease-free survival rates at 3 and 5 years were not different (p = 0.26 and p = 0.71 respectively), and neither were overall survival rates (p = 0.19 and p = 0.64 respectively), nor local recurrence rates (RR 0.88, 95% CI 0.63-1.23). CONCLUSIONS: Laparoscopic surgery for rectal cancer is associated with similar short-term and long-term oncologic outcomes compared to open surgery. The oncologic quality of extracted specimens seems comparable regardless of the approach used.


Assuntos
Laparoscopia , Margens de Excisão , Neoplasias Retais/cirurgia , Intervalo Livre de Doença , Humanos , Excisão de Linfonodo , Neoplasia Residual , Ensaios Clínicos Controlados Aleatórios como Assunto , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
2.
Pol J Pathol ; 67(1): 60-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27179276

RESUMO

The application of Fourier transform infrared (FTIR) microspectroscopy for the analysis of biomolecular composition of adrenal gland tumors is described. Samples were taken intraoperatively from three types of adrenal lesions: adrenal adenoma (ACA), adrenal cortical hyperplasia (ACH), both derived from adrenal cortical cells, and pheochromocytoma (Ph) derived from chromaffin cells of the adrenal medulla. The specimens were cryo-sectioned and freeze-dried. Since the investigated lesions originated from different cell types, it was predictable that they might differ in biomolecular composition. The experimental results were used to determine which absorption bands differentiate the analyzed samples the most. The main difference was observed in the lipid functional groups. The experimental results indicated that the level of lipids was higher in both the adenoma and the hyperplasia samples compared to pheochromocytomas. In contrast, the level of proteins was higher in the pheochromocytomas. Furthermore, differences within the range of nucleic acids and carbohydrates were observed in the studied adrenal gland tumor types.


Assuntos
Neoplasias das Glândulas Suprarrenais/química , Adenoma Adrenocortical/química , Feocromocitoma/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Neoplasias das Glândulas Suprarrenais/metabolismo , Adenoma Adrenocortical/metabolismo , Humanos , Hiperplasia/metabolismo , Lipídeos/análise , Feocromocitoma/metabolismo , Proteínas/análise
3.
Analyst ; 140(7): 2101-6, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25519296

RESUMO

The adrenal glands are small endocrine organs located on the bottom pole of each kidney. Anatomically they are composed of cortical and medullar parts. Due to dysfunctional processes they can transform into the pathological lesions (in both cortex and medulla). The incidentally detected adrenal lesions have become an arising clinical problem nowadays. The crucial issue for an accurate treatment strategy is relevant diagnosis. Distinguishing between benign and malignant lesions is often difficult during the standard histological examination. Hence the alternative methods of differentiation are investigated. One of them is Fourier transform infrared spectroscopy which allows the analysis of the biomolecular composition of the studied tissue. In this paper we present the very preliminary FTIR studies for defining the biomolecular pattern of three types of adrenal lesions: adenoma (AA) and adrenal cortical hyperplasia (ACH) - both derived from adrenal cortex as well as pheochromocytoma (PCC) - from the medullar part of the gland. All studied cases were classified as benign lesions. The general observations show that cortically derived tissues are rich in lipids and they are rather protein depleted while for medullar pheochromocytoma there is the opposite relationship. Furthermore, the unequivocal differences were noticed within the "fingerprinting" range. In addition subtle shifts in absorption band positions were observed between studied cases.


Assuntos
Neoplasias das Glândulas Suprarrenais/química , Espectroscopia de Infravermelho com Transformada de Fourier , Neoplasias das Glândulas Suprarrenais/patologia , Humanos , Hiperplasia/patologia , Feocromocitoma/química , Feocromocitoma/patologia
4.
Acta Chir Belg ; 115(6): 397-403, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26763837

RESUMO

INTRODUCTION: Mechanical bowel obstruction (MBO) remains one of the most common abdominal surgical emergencies. The aetiology of MBO depends on the population demographics and period of time in which a given population was studied. We are presenting the results of an analysis covering 145 years of observations based on patients operated in our department. METHODS: The single centre retrospective analysis included 1825 patients with MBO. They were divided into 4 groups depending on the years in which they were treated : group 1 (1868-1898), group 2 (1956-1970), group 3 (1987-1999), group 4 (2000-2013). The analysis covered the sex distribution, the mean age of patients versus the life expectancy and changes in MBO aetiology in every period. RESULTS: We noticed an increase in the mean age and the growing divergence between life expectancy. Additionally, an increasing percentage of women were observed. There were also significant changes in the aetiology. An increase in MBO caused by cancer was observed. The rate of strangulated hernias doubled in the second period of time, and then it gradually decreased. Intestinal volvulus was common in the first period and became one of the rarest causes of MBO in the subsequent periods. MBO due to adhesions remained at the same level. It became, however, the most common cause in the last period. CONCLUSIONS: Within nearly 150 years significant changes occurred in the demographics and aetiology of MBO. Currently, the most common cause is peritoneal adhesions after previous surgeries. Although our results represent a single centre experience, they may reflect changing patterns in MBO in the Polish population over time.


Assuntos
Obstrução Intestinal/epidemiologia , Obstrução Intestinal/patologia , Adulto , Fatores Etários , Feminino , Hérnia Abdominal/complicações , Humanos , Neoplasias Intestinais/complicações , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Aderências Teciduais/complicações
6.
J Physiol Pharmacol ; 70(6)2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32084651

RESUMO

Subclinical arterial damage connected with endothelial dysfunction is a common denominator of cardiovascular complications in a variety of metabolic diseases, including obesity. The aims of the study was to assess functional vascular changes measured by flow-mediated dilatation (FMD) and nitroglycerin-mediated dilation (NMD) of brachial artery, and to measure vascular structural alterations estimated by carotid intima-media complex thickness (IMT) in short- (10 days) and medium-term (6 months) time after bariatric surgery in patients with extreme obesity. Anthropometric, blood pressure (BP), FMD, NMD, IMT measurements, and laboratory assessment were performed on patients who met the eligibility criteria for bariatric surgery (age 18 - 60 years old, BMI ≥ 40.0 kg/m2 or with BMI 35.0 - 39.9 kg/m2 and co-morbidities), at baseline and during follow-up. The study population consisted of 71 patients: mean SD aged 45.6 (± 10.9) years; BMI = 47.7 (± 6.1) kg/m2; 45% of them were men). A significant reduction of systolic BP, glucose, HDL cholesterol, leptin, insulin and HOMA-IR were observed 10 days post intervention. A significant increase of FMD values was observed in the entire group 6 months after surgery (median (IQR) 6.2 (2.9 - 10.3) versus 8.5 (6.1 - 16.6), P < 0.05). Changes of NMD were insignificant. Carotid IMT diminished significantly after 6 months (median (IQR) 0.6 (0.5 - 0.7) versus 0.6 (0.5 - 0.6) mm, P < 0.05). A subgroup analysis revealed that FMD parameters had improved significantly after 6 months, mainly in men, hypertensives, and in the Roux-en Y bypass (RYGB) subgroup. In conclusion, endothelial function and subclinical atherosclerosis improved after bariatric surgery in patients with extreme obesity. A lack of changes of the dilatation independent of endothelial function may indicate the persistence of residual changes in the vascular bed.


Assuntos
Cirurgia Bariátrica/métodos , Espessura Intima-Media Carotídea , Obesidade Mórbida/cirurgia , Adulto , Aterosclerose/etiologia , Aterosclerose/cirurgia , Artéria Braquial/metabolismo , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Nitroglicerina/farmacologia , Estudos Prospectivos , Fatores de Tempo , Vasodilatação
7.
J Clin Invest ; 72(6): 2007-13, 1983 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6643683

RESUMO

Fragment E1, a product of plasmic digestion of cross-linked fibrin, binds specifically in vitro to polymerized fibrin but not to fibrinogen. Purified human Fragment E1 was radiolabeled with 125I or 131I by the Iodogen technique. The uptake of radioiodinated Fragment E1 in vitro into forming or preformed clots was demonstrated. Animal biodistribution studies of radioiodinated Fragment E1 showed its rapid removal from the circulation; radioactive catabolites did not reside long in any organ and were excreted in the urine. The uptake in vivo was evaluated in pigs with preexisting venous thrombi of various ages from 1 h up to 5 d at the time of intravenous systemic injection of the tracer. Radioiodinated fibrinogen was also injected into the same animals to compare the uptake of the two tracers. Thrombus-to-blood ratios for Fragment E1 averaged 43:1 (range 10-108) and 29:1 (range 8-107) in thrombi 1-6 h and 1-5 d old, respectively. In contrast, mean thrombus-to-blood ratios for fibrinogen were, in the same time intervals, 26:1 (range 17-41) and 2:1 (range 0.5-3.9), respectively. It is concluded that radioiodinated Fragment E1 is a specific marker of thrombi in vivo: its uptake by fresh thrombi is better than that of labeled fibrinogen and, in contrast to radioiodinated fibrinogen, this fragment is incorporated into old thrombi as well.


Assuntos
Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Fibrina/metabolismo , Fibrinogênio/metabolismo , Tromboflebite/metabolismo , Animais , Testes de Coagulação Sanguínea , Humanos , Técnicas In Vitro , Radioisótopos do Iodo , Marcação por Isótopo , Suínos
8.
J Clin Invest ; 83(6): 1916-24, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2542377

RESUMO

Fibrinogen degradation products (FDP) D and E are typically present in blood of patients with disseminated intravascular coagulation and related conditions in which granulocyte (PMN) defense against bacterial infection may be compromised. This study was intended to determine whether FDP modify PMN functions critical to their bactericidal activity. Incubation of human PMN and Escherichia coli with 50-100 micrograms/ml FDP did not affect phagocytosis, but reduced by greater than 90% the cells' ability to inhibit bacterial colony growth compared with control PMN incubated with albumin or fibrinogen. FDP (10-100 micrograms/ml) inhibited PMN O2- release and chemotaxis stimulated by FMLP by 17-50% (P less than 0.005) and 41% (P less than 0.01), respectively. Fragment E3, and not fragment D1, was primarily responsible for inhibition of FMLP-induced PMN O2- release. Phorbol myristate acetate (10 ng/ml), 1-oleoyl-2-acetylglycerol (10(-6) M), AA (4.2 x 10(-5) M), and zymosan-activated serum-stimulated PMN O2- release were also decreased 37-63% by FDP compared with control protein. There are at least two mechanisms by which FDP may impair PMN responses. With respect to FMLP, FDP (16-100 micrograms/ml) inhibited specific binding to the cell surface over a ligand concentration range of 1.4-85 nM [3H]FMLP. In contrast, FDP did not effect the extent of phorbol ester binding to PMN but blocked activation of protein kinase C. These data suggest that elevated plasma FDP inhibit several PMN functions critical to the bactericidal role of these inflammatory cells.


Assuntos
Atividade Bactericida do Sangue , Produtos de Degradação da Fibrina e do Fibrinogênio/fisiologia , Neutrófilos/fisiologia , Consumo de Oxigênio , Adulto , Ácidos Araquidônicos/metabolismo , Fatores de Coagulação Sanguínea/farmacologia , Quimiotaxia de Leucócito , Ativação Enzimática , Humanos , N-Formilmetionina Leucil-Fenilalanina/metabolismo , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/metabolismo , Neutrófilos/microbiologia , Fagocitose , Ligação Proteica , Proteína Quinase C/metabolismo , Superóxidos/metabolismo , Acetato de Tetradecanoilforbol/metabolismo
9.
Exp Clin Endocrinol Diabetes ; 115(6): 401-4, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17701888

RESUMO

UNLABELLED: Adrenocortical oncocytoma is extremely rarely found. Only a little more than thirty cases of adrenal oncocytoma, mainly nonfunctioning and benign, have been reported in the literature. Adrenal mass 150 x 160 x 172 mm in size and enlarged periarterial lymph nodes were found in CT examination performed in 51-year-old male. Main complaints: weight loss, general asthenia and abdominal pain. PHYSICAL EXAMINATION: elevated blood pressure (180/120 mmHg), no features typical of Cushing's syndrome. Abnormal laboratory findings: oral glucose tolerance test revealed diabetes, elevated serum dehydroepiandrosterone-sulfate (1101.9 microg/dl; normal, 59-452), elevated serum cortisol following overnight 1 mg dexamethasone test (5.1 microg/dl; normal, <1.8), increased urinary excretion of 17- hydroxycorticosteroids (18.1 mg/24 h; normal, 2.0-7.0) with pathological response to high-dose dexamethason test (16.6 mg/24). On laparotomy, the lesion was considered unresectable because of evident - confirmed by intraoperative ultrasound - tumour infiltration of the inferior caval vein. The large biopsy specimen was obtained for histological examination in which tumour fulfilled criteria proposed by Bisceglia et al. for adrenocortical oncocytic borderline tumour. On immunohistochemistry, the lesion showed cytoplasmic reaction for cytokeratin, vimentin and synaptophysin. The presented case appears to be the first malignant and functioning adrenocortical oncocytic tumour reported and confirms the complexity of its biology.


Assuntos
Adenoma Oxífilo/patologia , Neoplasias do Córtex Suprarrenal/patologia , Adenoma Oxífilo/metabolismo , Adenoma Oxífilo/cirurgia , Neoplasias do Córtex Suprarrenal/metabolismo , Neoplasias do Córtex Suprarrenal/cirurgia , Antineoplásicos Hormonais/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Mitotano/administração & dosagem , Proteínas de Neoplasias/metabolismo , Veias Cavas/patologia
10.
Surg Endosc ; 20(1): 14-29, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16247571

RESUMO

BACKGROUND: Emergency laparoscopic exploration can be used to identify the causative pathology of acute abdominal pain. Laparoscopic surgery also allows treatment of many intraabdominal disorders. This report was prepared to describe the effectiveness of laparoscopic surgery compared to laparotomy or nonoperative treatment. METHODS: A panel of European experts in abdominal and gynecological surgery was assembled and participated in a consensus conference using Delphi methods. The aim was to develop evidence-based recommendations for the most common diseases that may cause acute abdominal pain. RECOMMENDATIONS: Laparoscopic surgery was found to be clearly superior for patients with a presumable diagnosis of perforated peptic ulcer, acute cholecystitis, appendicitis, or pelvic inflammatory disease. In the emergency setting, laparoscopy is of unclear or limited value if adhesive bowel obstruction, acute diverticulitis, nonbiliary pancreatitis, hernia incarceration, or mesenteric ischemia are suspected. In stable patients with acute abdominal pain, noninvasive diagnostics should be fully exhausted before considering explorative surgery. However, diagnostic laparoscopy may be useful if no diagnosis can be found by conventional diagnostics. More clinical data are needed on the use of laparoscopy after blunt or penetrating trauma of the abdomen. CONCLUSIONS: Due to diagnostic and therapeutic advantages, laparoscopic surgery is useful for the majority of conditions underlying acute abdominal pain, but noninvasive diagnostic aids should be exhausted first. Depending on symptom severity, laparoscopy should be advocated if routine diagnostic procedures have failed to yield results.


Assuntos
Abdome/cirurgia , Tratamento de Emergência , Medicina Baseada em Evidências , Laparoscopia , Guias de Prática Clínica como Assunto , Endoscopia , Europa (Continente) , Humanos , Sociedades Médicas
11.
Cancer Res ; 43(4): 1633-5, 1983 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6831411

RESUMO

Salivary gland extract from the South American leech Haementeria ghilianii, administered i.v. on the same day as the i.v. inoculation of T241 sarcoma cells, completely suppresses colonization of the mediastinal lymph nodes and markedly reduces the number and size of lung tumor colonies produced by this tumor. Additional studies indicate that the extract contains various types of proteinase inhibitors and has the capacity to inhibit clotting and platelet aggregation by tumor material and collagen. Although not yet proved by direct evidence, these activities may be involved in the inhibitory effect of lung tumor colonization by the leech extract.


Assuntos
Neoplasias Pulmonares/fisiopatologia , Glândulas Salivares/fisiologia , Sarcoma Experimental/fisiopatologia , Extratos de Tecidos/farmacologia , Animais , Divisão Celular/efeitos dos fármacos , Sanguessugas , Camundongos , Camundongos Endogâmicos , Agregação Plaquetária/efeitos dos fármacos , Especificidade da Espécie
12.
Eur J Surg Oncol ; 42(6): 779-87, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27156809

RESUMO

INTRODUCTION: Progressive skeletal muscle loss (sarcopenia) is a negative prognostic factor in patients treated for colorectal cancer. Nevertheless, the clinical impact of those changes in body composition has been analyzed only in patients undergoing open resections. The aim of the study was to assess whether laparoscopy may eliminate the deleterious prognostic impact of sarcopenia and whether the combination with enhanced recovery after surgery (ERAS) protocol may improve postoperative recovery also in sarcopenic patients. METHODS: The study included 124 (73M/51F, mean age 65.9 years) patients undergoing elective laparoscopic colorectal resection for cancer. In all of them 16-item ERAS protocol was applied. The L3 skeletal muscle area identified on a preoperative CT scan was used to calculate skeletal muscle index and assess for sarcopenia and myosteatosis. The entire study group was divided into groups regarding the presence of sarcopenia or myosteatosis. The outcome measures were: length of hospital stay, complication rate and functional recovery parameters. RESULTS: The prevalence of sarcopenia and myosteatosis was 27.4% and 38.7%, respectively. There was no association between the presence of sarcopenia or myosteatosis and postoperative complications. There were also no differences in the length of stay or readmission rates. Functional recovery (time to first flatus, oral diet tolerance and mobilization) was similar regardless of the presence of muscle depletion. CONCLUSIONS: In contrary to traditional surgical approach, laparoscopy can reduce the negative impact of sarcopenia and myosteatosis on treatment results. ERAS protocol does not affect negatively the surgical outcomes in sarcopenic patients, compared to patients without changes in body skeletal mass.


Assuntos
Neoplasias Colorretais , Sarcopenia , Idoso , Procedimentos Cirúrgicos Eletivos , Humanos , Laparoscopia , Tempo de Internação , Complicações Pós-Operatórias/epidemiologia
13.
Biochim Biophys Acta ; 251(3): 292-302, 1971 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-11452869

RESUMO

1. Tobacco mosaic virus (TMV) protein has in near ultraviolet a complex but well resolved circular dichroism (CD) spectrum at room temperature. There are seven positive bands at 248, 252, 257, 265, 274, 281 and 291 nm, and a negative one at 296 nm. The CD spectrum is pH-dependent. The shape of the pH-dependence curves and the comparison with CD spectra of model compounds suggest that the bands at 248, 252 and 257 nm are mainly caused by phenylalanyl, those at 265, 274 and 281 nm by tyrosyl, and those at 291 and 296 nm by tryptophanyl side chains. 2. Only insignificant changes of the tertiary structure seem to occur between pH 6.5 and 8.5. Changes in ellipticity of TMV protein during the pH-induced polymerization reaction suggest that: (1) tyrosyl residues are involved in the binding of subunits, (2) phenylalanyl residues seem to be transferred to a less rigid environment, and (3) tryptophanyl residues are not essential for the reaction. 3. The proteins of several TMV strains and mutants studied have similar far ultraviolet CD spectra and apparently do not differ significantly in their structure. Their near ultraviolet CD spectra are, however, different. Replacements involving aliphatic amino acids do not change considerably the near ultraviolet CD spectra. On the other hand, replacements involving aromatic amino acids have a great effect on the spectra rendering possible identification of CD bands and recognition of the aromatic amino acid residues responsible for optical activity.


Assuntos
Capsídeo/química , Vírus do Mosaico do Tabaco/química , Vírus do Mosaico do Tabaco/genética , Sequência de Aminoácidos , Capsídeo/genética , Capsídeo/isolamento & purificação , Dicroísmo Circular , Solanum lycopersicum/virologia , Poaceae/virologia , Conformação Proteica , Espectrofotometria Ultravioleta
14.
Biochim Biophys Acta ; 924(1): 45-53, 1987 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-2950931

RESUMO

Fragments E1 and E2, plasmic degradation products of crosslinked fibrin, bind specifically to polymers of fibrin. A mixture of these fragments, denoted as fragment E1,2, was radiolabeled with 111In after covalently attaching metal chelating groups (diethylenetriaminepentaacetic acid, DTPA) to the fragment, using two approaches. In the first approach, DTPA groups were attached directly to purified fragment E1,2. In the second approach, attachment sites of DTPA groups were directed away from the active region of the molecule by having fragment E1,2 bound in complex, with its active sites protected during the derivatization. Direct attachment of DTPA groups to fragment E1,2 resulted in complete loss of binding to fibrin in vitro. When derivatized in complex, 111In-DTPA-fragment E1,2 retained a higher degree of binding to human fragment DD and human plasma clots in vitro than did radioiodinated fragment E1, even when up to eight DTPA groups were attached per molecule of fragment E1,2.


Assuntos
Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Índio/metabolismo , Ácido Pentético/metabolismo , Radioisótopos/metabolismo , Produtos de Degradação da Fibrina e do Fibrinogênio/isolamento & purificação , Fibrinolisina , Humanos , Cinética , Ligação Proteica
15.
Biochim Biophys Acta ; 584(2): 284-7, 1979 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35237

RESUMO

The role of plasmic degradation products of human crosslinked fibrin on polymerization of fibrin monomer and clot formation was studied. Both reactions were inhibited by Fragment DD, which formed a complex with fibrin monomer in a molar ratio 1 : 1. The rate of polymerization was slightly increased by Fragment E but it was not affected by (DD)E complex and Fragment A. Approximately the same amount of fibrin was formed in the presence and absence of Fragments A, E and the complex. It was concluded that of the degradation products of crosslinked fibrin, only Fragment DD is a potent anticoagulant at physiologic pH. The (DD)E complex is inert and Fragments A and E have only marginal effects.


Assuntos
Fibrina , Fibrinolisina , Coagulação Sanguínea , Humanos , Concentração de Íons de Hidrogênio , Substâncias Macromoleculares
16.
Biochim Biophys Acta ; 576(1): 39-50, 1979 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-153766

RESUMO

The predominant high molecular weight products of plasmic digestion of human crosslinked fibrin Fragments DD, E and (DD)E complex were purified by column gel filtration in a non-dissociating buffer or by ion-exchange chromatography on DEAE-cellulose. The structure of the degradation products was studied by proteolytic degradation, polyacrylamide gel electrophoresis immunodiffusion and sucrose density gradient centrifugation. Unaltered derivatives were very resistant to proteolytic degradation by plasmin. In the the presence of 10 mM EDTA the (DD)E complex did not dissociate, but similar to Fragment DD, became susceptible to plasmic degradation forming Fragment D derivatives. The (DD)E complex dissociated in 3 M urea at pH 5.5, had an altered conformation as evidenced by its aggregability and by its increased susceptibility to degradation by plasmin resulting in the formation of Fragment d. The gammagamma chain remnants of Fragment DD were attacked first, followed by cleavage of the beta chain remnants. It is concluded that plasmin resistance is a function of the intact structure and it is not directly dependent on the presence of the crosslink bonds or calcium ions.


Assuntos
Fibrina , Fibrinolisina , Humanos , Imunodifusão , Substâncias Macromoleculares , Peso Molecular , Oxirredução , Fragmentos de Peptídeos/análise , Conformação Proteica , Ureia
17.
Biochim Biophys Acta ; 427(1): 1-14, 1976 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-130927

RESUMO

The molecular weight of Fragment D derivatives obtained from plasmic digests of fibrinogen and cross-linked fibrin was determined by equilibrium sedimentation and compared with the summated molecular weight of their polypeptide chains observed after electrophoresis of reduced protein in sodium dodecyl sulfate polyacrylamide gels. The measured molecular weight of Fragment D (Stage 2) of fibrinogen is 103 500, which is compatible with a molecule containing only one each of the Aalpha (13 000), Bbeta (43 000) and gamma (39 000) chain remnants. Fragment D-D of cross-linked fibrin has a molecular weight of 189 000, compatible with a molecule containing one isopeptide-bound gamma-gamma chain (80 000) and two each of Bbeta (43 000) and Aalpha (13 000) chain remnants. The NH2-terminal amino acid residues of the Fragment D derivatives were measured quantitatively using a thioacetic-thioglycolic acid method, and molar quantities were calculated on the basis of the molecular weights determined by equilibrium sedimentation. Fragment D preparations obtained from Stage 2 and Stage 3 digests of fibrinogen have 3 mol of NH2-terminal amino acids per molecule, while Fragment D-D has seven. These data support the view that two Fragment D molecules, each of three polypeptide chains, are derived by plasmic degradation from each fibrinogen molecule, and that an isopeptide-bound, six chain Fragment D-D molecule is released from cross-linked fibrin by plasmin. Equlibrium sedimentation measurement of the molecular weights of Fragment X (Stage 1 and Stage 2) and Fragment Y are 265 000 and 148 000, respectively. These values are compatible with asymmetric cleavages of Fragment X to Fragments Y and D (Stage 2), and of Fragment Y to Fragments D (Stage 2) and E, and with a fibrinogen model in which the two halves are joined by disulfide bonds only in the amino-terminal regions.


Assuntos
Fibrina , Fibrinogênio , Eletroforese em Gel de Poliacrilamida , Produtos de Degradação da Fibrina e do Fibrinogênio , Fibrinolisina , Humanos , Substâncias Macromoleculares , Peso Molecular , Fragmentos de Peptídeos/análise
18.
Biochim Biophys Acta ; 400(2): 189-99, 1975 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-126081

RESUMO

Fibrinogen, coagulable plasmic derivatives (Fragments X) and Fragments Y, D and E were studied by negative staining electron microscopy. Fragment X obtained from Stage 1 digests and fibrinogen were both globular, while Fragment X of Stage 2 digests appeared as a nodular filament. The Stage 1 and Stage 2 Fragment X preparations had approximately the same molecular weight, but could be differentiated by several subtle differences in polypeptide chain structure. Fragments Y and D were also filamentous, although shorter than Fragment X (Stage 2), and Fragment E appeared as a small, compact or folded filament. These results agree with the concept that fibrinogen consists of a strand of nodules connected by thin strands, folded into a compact, spherical shape. The molecule opens up when stabilizing bonds are disrupted or liberated by plasmin. The data are compatible with a fibrinogen molecule in which the two halves are linked by a single locus of disulfide bonds at the amino terminus and with the asymmetric hypothesis of plasmic degradation to Fragments X, Y, D and E.


Assuntos
Dissulfetos/análise , Fibrinogênio/análise , Fibrinolisina , Sítios de Ligação , Testes de Coagulação Sanguínea , Humanos , Microscopia Eletrônica , Fragmentos de Peptídeos/análise , Ligação Proteica , Conformação Proteica
19.
Eur Surg ; 47(5): 266-270, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26566387

RESUMO

BACKGROUND: Surgical treatment of morbid obesity is becoming an increasingly important approach for the treatment of this condition. However, knowledge about the possibility of surgical procedures among general practitioners is far from satisfactory. The source of the problem might be due to a lack of information about bariatric surgery in university curriculum. METHODS: We assessed the knowledge of students from four Polish medical universities. The survey was conducted among 468 students, in their sixth (final) year of study. The survey included two parts-the first nine questions assessed of the level of the students' knowledge about the methods of surgical treatment of obesity, and the following three questions allowed for an evaluation of the amount of information on metabolic surgery provided to students during surgery courses. RESULTS: The results demonstrate a low level of knowledge on the possibility of applying metabolic surgery to treat morbid obesity. The students themselves expressed a need to improve their knowledge and favorably assessed the proposition of expanding the curriculum to include more information on the subject of metabolic surgery. CONCLUSION: The awareness of surgical treatment for morbid obesity among medical students should be improved. The development of an interesting curriculum that is based on current guidelines should be undertaken.

20.
Ann R Coll Surg Engl ; 97(6): e96-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26320770

RESUMO

Median arcuate ligament syndrome (MALS) is a rare disorder due to coeliac trunk compression by the median arcuate ligament, resulting in coeliac artery stenosis characterised by chronic, recurrent abdominal pain. Patients with MALS are often middle-aged females presenting with a triad of postprandial epigastric pain, weight loss and abdominal bruit. It is a diagnosis of exclusion and confirmed by computed tomography or magnetic resonance imaging. Laparoscopic or open surgical decompression are the only treatment options in MALS. We present two cases of MALS treated by laparoscopic decompression as well as a literature review on this treatment.


Assuntos
Artéria Celíaca/anormalidades , Constrição Patológica/cirurgia , Descompressão Cirúrgica/métodos , Adulto , Artéria Celíaca/diagnóstico por imagem , Artéria Celíaca/cirurgia , Constrição Patológica/diagnóstico por imagem , Feminino , Humanos , Laparoscopia/métodos , Síndrome do Ligamento Arqueado Mediano , Tomografia Computadorizada por Raios X
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