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1.
Artigo em Inglês | MEDLINE | ID: mdl-39147008

RESUMO

OBJECTIVE: To explore the causal pathways underlying the short-term effects of deep dry needling (DDN) in people with chronic neck pain. DESIGN: Explanatory longitudinal mediation analysis with repeatedly measured mediators and outcomes. SETTING: Primary care setting. PARTICIPANTS: Patients (N=128) with chronic neck pain. INTERVENTIONS: Participants were randomized into 2 groups; DDN of the neck muscles combined with stretching (n=64) and stretching alone (n=64). MAIN OUTCOME MEASURES: Two outcomes (pain intensity and neck pain-related disability) and 3 candidate mediators (local pressure pain thresholds [PPTs], cervical range of motion [ROM], and neck muscle strength) were included. Pain intensity was also included as a competing mediator in the mediation analysis for disability. Mediators and outcomes were measured at 3 time points: after intervention and at 2- and 4-week follow-up. Age, sex, and the baseline values of the outcome and mediators were included as pretreatment mediator-outcome confounders. RESULTS: Reductions in pain intensity strongly mediated the short-term effects of DDN on disability, from after intervention to 4-week follow-up. In addition, the attenuation of local hypersensitivity (via increasing PPTs) moderately mediated reductions in pain intensity at each time point. On the other hand, gains in cervical ROM contributed to reducing neck pain-related disability. Changes in muscle strength did not lead to better outcomes. CONCLUSIONS: This novel study demonstrated that DDN effect on neck pain-related disability is strongly driven by the analgesic effects of this physical therapy modality. Increasing PPTs and cervical ROM seem to be also part of the mechanisms behind DDN's effect.

2.
Int Orthop ; 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39331067

RESUMO

PURPOSE: To report the radiological and clinical outcomes of non-vascularized coracoid process autografts used for glenoid reconstruction during revision shoulder arthroplasty. MATERIAL AND METHOD: This is a retrospective, monocentric study from January 2016 to October 2022 targeting patients treated with a coracoid bone graft for glenoid reconstruction during revision of shoulder arthroplasty. The primary outcome measures were coracoid graft union rate and graft-implant osseointegration. Secondary outcome measures included clinical and CT-scan identified radiological complications and functional outcomes as measured by the Visual Analog Scale (VAS), Range of Motion (ROM), Subjective Shoulder Value (SSV), Constant score (absolute and ponderate), and ASES score. RESULTS: Fifteen patients (9 males, 6 females; mean age 66.9 years, range 38-85) were included. At a mean follow-up of 20.9 months (range 12-56 months), 93.3% achieved complete graft integration. One case of partial lysis without baseplate loosening was noted. Regarding range of motion, the mean forward elevation was 130° (range 90°-170°), external rotation at the side 25° (range 10°-40°), external rotation in 90° of abduction 45° (range 10°-80°), and internal rotation 52° (range 10-80°). The mean VAS for pain was 1.1 (range 0-8), mean SSV 67.3% (range 40-90%), mean ASES score 85.5 (range 65-98.3), mean Absolute Constant score 58.6 (range 21-83), and mean Ponderate Constant score 77.5% (range 28.8-110.7%). No neurological injuries were reported. CONCLUSION: Utilizing a non-vascularized coracoid graft during shoulder arthroplasty revision is a safe, reproducible, and time-efficient technique that demonstrated satisfactory osseointegration, implant stability, good functional results, and a low complication rate.

3.
J Shoulder Elbow Surg ; 32(7): 1401-1411, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37001795

RESUMO

BACKGROUND: Frozen shoulder (FS) is a highly disabling pathology of poorly understood etiology, which is characterized by the presence of intense pain and progressive loss of range of motion. The aim of this study was to evaluate the effect of adding a central nervous system (CNS)-focused approach to a manual therapy and home stretching program in people with FS. METHODS: A total of 34 patients with a diagnosis of primary FS were randomly allocated to receive a 12-week manual therapy and home stretching program or manual therapy and home stretching program plus a CNS-focused approach including graded motor imagery and sensory discrimination training. The Shoulder Pain and Disability Index score, self-perceived shoulder pain (visual analog scale score), shoulder range of motion, and the Patient-Specific Functional Scale score were measured at baseline, after a 2-week washout period just before starting treatment, after treatment, and at 3 months' follow-up. RESULTS: No significant between-group differences in any outcome were found either after treatment or at 3 months' follow-up. CONCLUSION: A CNS-focused approach provided no additional benefit to a manual therapy and home stretching program in terms of shoulder pain and function in people with FS.


Assuntos
Bursite , Sistema Nervoso Central , Manipulações Musculoesqueléticas , Dor de Ombro , Humanos , Terapia por Exercício , Manipulações Musculoesqueléticas/efeitos adversos , Modalidades de Fisioterapia/efeitos adversos , Amplitude de Movimento Articular , Dor de Ombro/terapia , Dor de Ombro/etiologia , Resultado do Tratamento
5.
Eur J Pediatr ; 180(9): 2879-2888, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33791862

RESUMO

Latin America (LATAM) children offer special insight into Severe Acute Respiratory Syndrome Coronavirus 2 (SARS COV2) due to high-risk race/ethnicity, variability in medical resources, diverse socioeconomic background, and numerous involved organ systems. This multinational study of LATAM youth examined the distinguishing features of acute or late multisystem SARS COV2 with versus without cardiac involvement. A consecutive sample of youth 0-18 years old (N = 98;50% male) presenting with multisystem SARS COV2 to 32 centers in 10 Latin American countries participating in a pediatric cardiac multi-imaging society were grouped as with versus without cardiac involvement, defined as abnormal echocardiographic findings or arrhythmia. Collected clinical data were analyzed by Student's t-test or Fisher's exact test. Cardiac (N = 48, 50% male) versus no cardiac (N = 50, 50% male) were similar in age; weight; nonrespiratory symptoms; and medical history. The cardiac group had 1 death and symptoms including coronary artery dilation, ejection fraction <50%, pericardial effusion, peripheral edema, arrhythmia, and pulmonary artery thrombus. The cardiac group had higher risk of ICU admission (77% vs 54%, p = 0.02); invasive ventilation (23% vs 4%,p = 0.007); vasoactive infusions (27% vs 4%, p = 0.002); prominent respiratory symptoms (60% vs 36%, p < 0.03); abnormal chest imaging (69% vs 34%, p = 0.001); troponin (33% vs 12%, p = 0.01); alanine aminotransferase (33% vs 12%, p = 0.02); and thrombocytopenia (46% vs 22%, p = 0.02). Receiver operating curve analysis showed that abnormal laboratories had 94% sensitivity and 98% negative predictive value on the need for ICU interventions.Conclusion: In LATAM children with multisystem SARS COV2, cardiac involvement was prevalent. Cardiac involvement was more likely to require ICU interventions, certain abnormal labs, and respiratory involvement. What is Known: • SARS COV2 can be asymptomatic in children but in some cases can have serious multisystemic involvement. • Hispanic ethnicity is purportedly at high risk of SARS COV2 in nations where they are often disadvantaged minority populations. What is New: • Latin American children presenting with multisystem SARS COV2 frequently have cardiac involvement which was associated with ICU interventions; prominent respiratory symptoms; abnormal chest X-ray; elevated troponin, ALT, and thrombocytopenia. • Elevated troponin, ALT or thrombocytopenia had high sensitivity and negative predictive value on the need for intensive care interventions.


Assuntos
COVID-19 , SARS-CoV-2 , Adolescente , Arritmias Cardíacas , Criança , Pré-Escolar , Cuidados Críticos , Feminino , Humanos , Lactente , Recém-Nascido , América Latina/epidemiologia , Masculino
6.
Gac Med Mex ; 156(5): 405-411, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33372941

RESUMO

INTRODUCTION: Various biomarkers based on blood counts have been useful for the prognosis of patients critically ill with COVID-19. OBJECTIVE: To describe the usefulness of the neutrophil-to-lymphocyte (NLR), monocyte-to-lymphocyte (MLR) and lymphocyte-to-platelet (LPR) ratios for the prognosis of mortality and ventilatory support requirement for COVID-19. METHOD: Retrospective cohort of clinical records of patients with COVID-19 who required hospital care. RESULTS: One-hundred and -twenty-five cases were analyzed; mean age was 51 years, and 60 % were of the male gender; 21.6 % had type 2 diabetes mellitus, and 18.4 % had hypertension. Mean leukocyte count was 9.5 x 103/µL, with a neutrophil mean of 8.0 x 103/µL. Mean NLR was 12.01, while for MLR it was 0.442, and for LPR, 373.07. Regarding the area under the curve, the following values were recorded for mortality: 0.594 for NLR, 0.628 for MLR and 0.505 for LPR; as for mechanical ventilation, the values were 0.581 for NLR, 0.619 for MLR and 0.547 for LPR. In the univariate analysis, an NLR value > 13 (OR: 2.750, p = 0.001) and an MLR of > 0.5 (OR: 2.069, p = 0.047) were associated with mortality; LPR showed no impact on mortality or respiratory support. CONCLUSION: NLR and MLR are useful for predicting mortality in patients with COVID-19.


INTRODUCCIÓN: Diversos biomarcadores basados en conteos sanguíneos han sido de utilidad para el pronóstico de los pacientes en estado crítico por COVID-19. OBJETIVO: Describir la utilidad de los índices neutrófilo/linfocito (INL), monocito/linfocito (IML) y linfocito/plaqueta (IPL) para el pronóstico de la mortalidad y necesidad de soporte ventilatorio por COVID-19. MÉTODO: Cohorte retrospectiva de registros clínicos de pacientes con COVID-19 que requirieron atención hospitalaria. RESULTADOS: Se analizaron 125 casos, la edad media fue de 51 años y 60 %, del sexo masculino; 21.6 % padecía diabetes mellitus tipo 2 y 18.4 %, hipertensión. La media de leucocitos fue 9.5 × 103/µL y la de neutrófilos, de 8.0 × 103/µL. La media del INL fue de 12.01; del IML, de 0.442 y del IPL, de 373.07. Respecto al área bajo la curva se registraron los siguientes valores en cuanto a mortalidad: INL, 0.594; IML, 0.628 e ILP, 0.505; en cuanto a ventilación mecánica: INL, 0.581; IML, 0.619 e ILP, 0.547. En el análisis univariado, INL > 13 (RM = 2.750, p = 0.001) e IML > 0.5 (RM = 2.069, p = 0.047) se asociaron a mortalidad; ILP no mostró impacto en la mortalidad ni en el soporte respiratorio. CONCLUSIÓN: INL e IML son de utilidad para predecir la mortalidad en pacientes con COVID-19.


Assuntos
COVID-19/sangue , COVID-19/mortalidade , Idoso , Idoso de 80 Anos ou mais , COVID-19/complicações , Estudos de Coortes , Feminino , Humanos , Contagem de Leucócitos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Monócitos , Contagem de Plaquetas , Prognóstico , Estudos Retrospectivos
7.
J Anat ; 234(4): 532-542, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30663783

RESUMO

This study aimed to investigate the spatial distribution and redistribution of lumbar erector spinae (ES) activity during a lumbar extension endurance task in pain-free participants and how this is modified in people with low back pain (LBP). High density surface electromyography (HDEMG) was recorded using 13 × 5 electrode grids placed over the lumbar ES in 13 LBP and 13 control participants while completing an Ito test to task failure. The root mean square of the HDEMG signals was computed, a topographical map of the EMG amplitude generated and the centre of the activity (centroid) determined throughout the task. The centroid of the EMG amplitude map was systematically more cranial (F = 6.09, P = 0.022) for the LBP participants compared with the control subjects. Regression analysis showed that the extent of redistribution of ES activity was associated with longer endurance. These results show that LBP participants utilised a different motor strategy to perform the endurance task, characterised by greater activation of more cranial regions of the ES and less redistribution of ES activity throughout the task. This study provides new insight into the functional activation of the lumbar ES and how it is modified when people have pain.


Assuntos
Dor Lombar/fisiopatologia , Região Lombossacral/fisiopatologia , Músculos Paraespinais/fisiopatologia , Adulto , Estudos de Casos e Controles , Estudos Transversais , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resistência Física , Adulto Jovem
8.
Gynecol Endocrinol ; 35(10): 909-912, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31023101

RESUMO

The plasminogen activator inhibitor type 1 (PAI-1) is the major determinant of fibrinolytic activity. PAI-1 concentrations are elevated in obesity, type 2 diabetes and metabolic syndrome (MetS). On the other hand, during menopause, fibrinolytic activity decreases and, consequently, PAI-1 concentration increases; however, it is debated whether menopause is an independent determinant factor of PAI-1 levels. The objective of this study was to evaluate the effect of hormonal and metabolic status on the concentration of PAI-1 in pre-and post-menopausal women. A case-control study was conducted in ninety pre-and post-menopausal women aged 45 to 55 years, matched by body mass index (BMI). Anthropometric measurements and biochemical determinations were performed on all participants. The fibrinolytic activity was determined by measuring PAI-1 by ELISA. Of all the women, 30% presented MetS. Women with MetS had higher values of PAI-1 (36.0 ± 19.1 vs 19.3 ± 14.8 ng/mL, p < .001); in contrast, no differences were observed when compared by hormonal status (20.7 ± 18.10 vs 20.2 ± 17.0 ng/mL, NS). The results of this study suggest that in women, MetS plays a more important role in the deterioration of the fibrinolytic mechanisms rather than their hormonal status. Therefore, the identification of cardio-metabolic factors is relevant to reduce the presence of thrombosis in post-menopausal women.


Assuntos
Menopausa/sangue , Síndrome Metabólica/sangue , Inibidor 1 de Ativador de Plasminogênio/sangue , Índice de Massa Corporal , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade
10.
Rev Gastroenterol Peru ; 37(1): 9-15, 2017.
Artigo em Espanhol | MEDLINE | ID: mdl-28489830

RESUMO

The hepatopulmonary syndrome (HPS) and portopulmonary hypertension (PPHN) are distinct pulmonary vascular complications of portal hypertension (PHT) and are associated with increased morbidity and mortality. OBJECTIVES: To describe the clinical and laboratory characteristics of patients with pulmonary hypertension and pulmonary vascular complications hospitalized at the Instituto Nacional de Salud del Niño. MATERIALS AND METHODS: We included patients with HTP hospitalized from January 2012 to June 2013 and that during its evolution progressed with SHP or HTPP. For analysis, they were divided into a first group of patients with liver cirrhosis and a second group with extrahepatic portal vein obstruction. RESULTS: Of 22 patients with HPT 45.5% were male and the age range was between 1 month and 17 years. The etiology in the group of cirrhosis (n=14) was: autoimmune hepatitis (35.7%), cryptogenic cirrhosis (35.7%), inborn error of metabolism (14.3%), chronic viral hepatitis C (7.15%) virus and atresia extra-hepatic bile ducts (7.15%). Pulmonary vascular complications more frequently occurred in patients with liver cirrhosis (1 case of HPS and a case of PPHTN). They most often dyspnea, asthenia, edema, malnutrition, ascites, hypersplenism and gastrointestinal bleeding from esophageal varices was found. Also, they had elevated ALT values, alkaline phosphatase and serum albumin values decreased. CONCLUSIONS: In children with pulmonary hypertension, pulmonary vascular complications are rare. In the evaluation of these patients pulse oximetry should be included to detect hypoxemia and ubsequently a Doppler echocardiography and contrast echocardiography necessary. Dueto the finding of systolic pulmonary hypertension it is necessary to perform right heart catheterization.


Assuntos
Síndrome Hepatopulmonar/diagnóstico , Hipertensão Portal/complicações , Hipertensão Pulmonar/diagnóstico , Adolescente , Criança , Pré-Escolar , Feminino , Síndrome Hepatopulmonar/etiologia , Hospitalização , Hospitais Pediátricos , Hospitais Públicos , Humanos , Hipertensão Pulmonar/etiologia , Lactente , Masculino , Peru , Estudos Prospectivos
11.
Inorg Chem ; 55(18): 9471-81, 2016 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-27571050

RESUMO

Stepwise reaction of W(CO)6 with tetramethylated bicyclic guanidinate ligands, characterized by a central C(N)3 unit joining two fused six-membered rings with CH2CMe2CH2 units spanning two of the nitrogen atoms, allowed isolation of W2(µ-CO)2(µ-TMhpp)2(η(2)-TMhpp)2, 1, a precursor of W2(TMhpp)4Cl2 ( J. Am. Chem. Soc. 2013 , 135 , 17889 ; TMhpp = [(CH2CMe2CH2)2(C(N)3)]). Subsequent heating of 1 followed by reaction with TlPF6 generates [W2(TMhpp)4](PF6)2, 2. Compound 1 has an edge-sharing bioctahedral (ESBO) arrangement with a W2(µ-CO)2(4+) core having semibridging carbonyl groups, while 2 has a paddlewheel structure with a W2(6+) core spanned by four tetramethyl-substituted bicyclic guanidinate ligands. This compound also has hexafluorophosphate anions along the metal-metal bond that are nestled within methylene groups with the aid of a network of weak C-H···F interactions that prevent a close approach of the fluorine atoms to the dimetal unit. Theoretical computations were carried out on ditungsten model complexes supported by three ligand sets: bicyclic guanidinate, guanidinate, and formamidinate. The computations show that the π-accepting ability of the carbonyl groups significantly lowers the energy of the σ* orbital, and thus, the energy falls below that of the δ orbital. This information along with the diamagnetism of both 1 and 2-as shown by the sharp signals in the (1)H NMR spectra that support a lack of unpaired electrons (S = 0)-is consistent with the electronic configuration of σ(2)π(2)σ*(2)δ(2) (π(2)δ(2)) and thus a formal bond order of 2 for 1 and σ(2)π(4) for the triple-bonded W2(6+) core in 2. A comparison of the W-W bond lengths in 2, its chloro precursor W2(TMhpp)4Cl2, and the corresponding analogue W2(hpp)4Cl2 shows a substantial effect from the axially coordinated ligand, distal lone pair in determining the length of the metal-metal bond for these paddlewheel species. The importance of the ligands in tuning the energy level of the metal-metal bonds that may lead to dramatic changes in physical properties is also discussed. It is noteworthy that bicyclic guanidinates with the strongest π-donating ability push upward the energy level of the δ orbital, thus allowing the compounds to be easily oxidized.

12.
Ann Vasc Surg ; 29(8): 1625-32, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26315791

RESUMO

BACKGROUND: To identify inherited factors: Protein C (PC), protein S (PS), antithrombin (AT), plasminogen (Plg), the activated PC resistance (APCR), prothrombin (PT) mutation G20210 A (PTG20210 A) and methylenetetrahydrofolate reductase C677 T polymorphism (MTHFR C677 T), as well as acquired-risk factors such as: diabetes mellitus, surgeries, smoking, obesity, hypertension, trauma, alcoholism, family history; and their association, in Mexican patients with diagnostic of thrombophilia. METHODS: Overall, 200 patients diagnosed with thrombophilia and 100 healthy controls. Commercial kits were used for the coagulometric tests and polymerase chain reaction, restriction fragment length polymorphism for molecular alterations. RESULTS: Alterations were found with an estimated prevalence to PC 0.65%, AT 2.04% and Plg 2.5%, APCR 2%, PT 20210 2%, and MTHFR 65%. The C677 T polymorphism of the MTHFR did not associate with acquired-risk factors so we can suppose that it is an independent risk factor. For the patients that only presented acquired-risk factors (21 of 200), the association smoking-alcoholism showed to be the cause of thrombosis with high risk. The following were also associated: smoking with AT, PC, and alcoholism; obesity with Plg; smoking with alcoholism, and PS deficiency. CONCLUSIONS: Risk factors for both primary and secondary and their association were present as a cause of thrombosis in the patients studied, and the possibility to suffer a recurrent thrombosis.


Assuntos
Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Mutação/genética , Plasminogênio/deficiência , Protrombina/genética , Trombofilia/etiologia , Trombose/etiologia , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , México , Fenótipo , Fatores de Risco , Trombofilia/diagnóstico , Adulto Jovem
13.
Rev Invest Clin ; 67(2): 122-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25938846

RESUMO

BACKGROUND: PAI-1 is the main inhibitor of fibrinolysis. Increase in PAI-1 levels has been associated with the risk of coronary disease; however, there are few studies on the relationship between subclinical atherosclerosis and PAI-1 levels. OBJECTIVE: The aim of this study was to analyze the relationship between PAI-1 level and carotid intima-media thickness in premenopausal and postmenopausal women without apparent cardiovascular disease. MATERIAL AND METHODS: A cross-sectional study was conducted in 142 women aged 45 to 60 years with no history of cardiovascular disease. Anthropometric and laboratory measurements were performed, including PAI-1 levels. All participants underwent a B-Mode ultrasound to measure intima-media thickness. Subclinical atherosclerosis was considered when intima-media thickness was ≥ 0.7 mm and/or an atheromatous plaque was observed. RESULTS: Postmenopausal women had greater intima-media thickness than premenopausal women (0.688 ± 0.129 vs. 0.621 ± 0.113 mm; p < 0.05). Compared to women with normal intima-media thickness, women with subclinical atherosclerosis had higher PAI-1 levels (23.2 ± 13.7 vs. 30.4 ± 20.7 ng/ml; p < 0.05). In all participants, intima-media thickness correlated with PAI-1 (r = 0.302; p = 0.01) and with age (r = 0.358; p = 0001). CONCLUSIONS: An increase in intima-media thickness was observed in postmenopausal women compared with premenopausal women. Asymptomatic women with increased intima-media thickness had higher PAI-1 levels. These findings suggest that fibrinolytic activity is low in the subclinical stage of atherosclerosis.


Assuntos
Aterosclerose/patologia , Espessura Intima-Media Carotídea , Inibidor 1 de Ativador de Plasminogênio/sangue , Pós-Menopausa , Aterosclerose/epidemiologia , Estudos Transversais , Feminino , Fibrinólise/fisiologia , Humanos , Pessoa de Meia-Idade , Pré-Menopausa
14.
J Am Chem Soc ; 136(27): 9580-9, 2014 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-24878393

RESUMO

Variable-temperature magnetic and structural data of two pairs of diruthenium isomers, one pair having an axial ligand and the formula Ru2(DArF)4Cl (where DArF is the anion of a diarylformamidine isomer and Ar = p-anisyl or m-anisyl) and the other one being essentially identical but devoid of axial ligands and having the formula [Ru2(DArF)4]BF4, show that the axial ligand has a significant effect on the electronic structure of the diruthenium unit. Variable temperature crystallographic and magnetic data as well as density functional theory calculations unequivocally demonstrate the occurrence of π interactions between the p orbitals of the chlorine ligand and the π* orbitals in the Ru2(5+) units. The magnetic and structural data are consistent with the existence of combined ligand σ/metal σ and ligand pπ/metal-dπ interactions. Electron paramagnetic resonance data show unambiguously that the unpaired electrons are in metal-based molecular orbitals.

15.
Inorg Chem ; 53(18): 9441-56, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25219791

RESUMO

The development of our understanding of the δ bond and its role in quadruple metal-metal bonding is described in terms of the conceptual advances and experimental and theoretical results achieved through a 50-year period beginning with the seminal report by Cotton and co-workers in 1964. The work behind the original discovery is described, along with the qualitative orbital description of the components of the quadruple bond. The effect of torsion about the metal-metal axis on the metal-metal bond length is described, together with the conclusion that this accords with a progressive loss of the δ component of the metal-metal bond. The important role of photoelectron spectroscopy in characterizing the loss of electrons from the metal-metal bonding orbitals is reviewed, as are the electron paramagnetic resonance results that establish that unpaired electrons, when present, populate metal-based orbitals. Other important results are described: destabilization of the metal-metal bond to produce strong reducing agents, exceptions to the expected orbital ordering, and the use of chiroptical properties to reveal additional information about the electronic structure of the metal-metal bond.

16.
Inorg Chem ; 53(4): 2288-95, 2014 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-24483772

RESUMO

An ionic edge-sharing bioctahedral (ESBO) species has been prepared having a tetramethylated bicyclic guanidinate with two fused six-membered rings characterized by a fairly flat N-C(N)-N skeleton and abbreviated as TMhpp. The anion has two W(IV) atoms bridged by two oxo groups; the metal atoms are also spanned by two bridging guanidinate ligands, and each has two monodentate chlorine atoms. The complex formulated as (H2TMhpp)2[W(µ-O)(µ-TMhpp)Cl2]2 has the shortest W-W distance (2.3318(8) Å) of any species with a σ(2)π(2) electronic configuration. The anion and cations are connected by hydrogen bonds. To unambiguously ascertain the existence of the double-bonded W2(µ-O)2 entity, density functional theory calculations and natural bond orbital analyses were done on an analogous but hypothetical species with a W2(µ-OH)2 core having trivalent tungsten atoms and a possible σ(2)π(2)δ(2) electronic configuration. The calculations decidedly support the presence of tungsten-oxo instead of tungsten-hydroxo groups and thus the existence of the double-bonded W2(µ-O)2 core. The strong bonding interaction between metal atoms is a clear indication that under certain circumstances the two octahedra in ESBO species do not behave as the sum of two mononuclear compounds.

17.
Gac Med Mex ; 150(4): 279-88, 2014.
Artigo em Espanhol | MEDLINE | ID: mdl-25098212

RESUMO

In order to identify the clinical approach of a sample of Mexican hematologists for primary immune thrombocytopenia (ITP) in adults in Mexico, we applied an electronic survey via the internet to identify common practices for the diagnosis and treatment of ITP and draw a comparison between the information from these hematologists with international guidelines or the international literature. The results were analyzed using measures of central tendency. The sample was 21 medical hematologists, predominantly from Mexico City (average age: 51.4 years). A total of 66.7% of the surveyed physicians use international guidelines to make therapeutic decisions, and 43% defined ITP including the numerical concept (< 100 x 10(9)/l). We found some differences between requested clinical exams and tests indicated by the guidelines. In first-line treatment (except emergency), 91% of the participants start with prednisone and 24% use dexamethasone. Danazol is used in persistent ITP by most (41%) of the specialists. In second-line treatment, 67% would indicate splenectomy. Some differences were found between clinical practice of the hematologists in Mexico versus guidelines recommendations.


Assuntos
Hematologia , Padrões de Prática Médica , Púrpura Trombocitopênica Idiopática/diagnóstico , Púrpura Trombocitopênica Idiopática/terapia , Adulto , Idoso , Humanos , Internacionalidade , México , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Literatura de Revisão como Assunto
18.
Phys Med Biol ; 69(5)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38295403

RESUMO

Objective.Compact ion imaging systems based on thin detectors are a promising prospect for the clinical environment since they are easily integrated into the clinical workflow. Their measurement principle is based on energy deposition instead of the conventionally measured residual energy or range. Therefore, thin detectors are limited in the water-equivalent thickness range they can image with high precision. This article presents ourenergy paintingmethod, which has been developed to render high precision imaging with thin detectors feasible even for objects with larger, clinically relevant water-equivalent thickness (WET) ranges.Approach.A detection system exclusively based on pixelated silicon Timepix detectors was used at the Heidelberg ion-beam therapy center to track single helium ions and measure their energy deposition behind the imaged object. Calibration curves were established for five initial beam energies to relate the measured energy deposition to WET. They were evaluated regarding their accuracy, precision and temporal stability. Furthermore, a 60 mm × 12 mm region of a wedge phantom was imaged quantitatively exploiting the calibrated energies and five different mono-energetic images. These mono-energetic images were combined in a pixel-by-pixel manner by averaging the WET-data weighted according to their single-ion WET precision (SIWP) and the number of contributing ions.Main result.A quantitative helium-beam radiograph of the wedge phantom with an average SIWP of 1.82(5) % over the entire WET interval from 150 mm to 220 mm was obtained. Compared to the previously used methodology, the SIWP improved by a factor of 2.49 ± 0.16. The relative stopping power value of the wedge derived from the energy-painted image matches the result from range pullback measurements with a relative deviation of only 0.4 %.Significance.The proposed method overcomes the insufficient precision for wide WET ranges when employing detection systems with thin detectors. Applying this method is an important prerequisite for imaging of patients. Hence, it advances detection systems based on energy deposition measurements towards clinical implementation.


Assuntos
Hélio , Água , Humanos , Hélio/uso terapêutico , Radiografia , Íons , Imagens de Fantasmas
19.
J Pain ; 25(6): 104471, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38232862

RESUMO

Gray matter (GM) changes are often observed in people with chronic spinal pain, including those with chronic whiplash-associated disorders (CWAD). These GM adaptations may be reversed with treatment, at least partially. Pain neuroscience education combined with exercise (PNE+Exercise) is an effective treatment, but its neural underlying mechanisms still remain unexplored in CWAD. Here, we performed both cross-sectional and longitudinal voxel-based morphometry to 1) identify potential GM alterations in people with CWAD (n = 63) compared to age- and sex-matched pain-free controls (n = 32), and 2) determine whether these GM alterations might be reversed following PNE+Exercise (compared to conventional physiotherapy). The cross-sectional whole-brain analysis revealed that individuals with CWAD had less GM volume in the right and left dorsolateral prefrontal cortex and left inferior temporal gyrus which was, in turn, associated with higher pain vigilance. Fifty individuals with CWAD and 29 pain-free controls were retained in the longitudinal analysis. GM in the right dorsolateral prefrontal cortex increased after treatment in people with CWAD. Moreover, the longitudinal whole-brain analysis revealed that individuals with CWAD had decreases in GM volumes of the left and right central operculum and supramarginal after treatment. These changes were not specific to treatment modality and some were not observed in pain-free controls over time. Herewith, we provide the first evidence on how GM adaptations to CWAD respond to treatment. PERSPECTIVE: This article presents which gray matter adaptations are present in people with chronic pain after whiplash injuries. Then, we examine the treatment effect on these alterations as well as whether other neuroplastic effects on GM following treatment occur.


Assuntos
Adaptação Fisiológica , Dor Crônica , Substância Cinzenta , Imageamento por Ressonância Magnética , Traumatismos em Chicotada , Humanos , Traumatismos em Chicotada/complicações , Traumatismos em Chicotada/diagnóstico por imagem , Masculino , Feminino , Adulto , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Dor Crônica/etiologia , Dor Crônica/diagnóstico por imagem , Dor Crônica/fisiopatologia , Estudos Transversais , Pessoa de Meia-Idade , Adaptação Fisiológica/fisiologia , Estudos Longitudinais , Terapia por Exercício
20.
Arch Med Res ; 55(5): 103032, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38971127

RESUMO

BACKGROUND: Adiposity favors several metabolic disorders with an exacerbated chronic pro-inflammatory status and tissue damage, with high levels of plasminogen activator inhibitor type 1 (PAI-1) and proprotein convertase subtilisin/kexin type 9 (PCSK9). OBJECTIVE: To demonstrate the influence of bariatric surgery on the crosstalk between PAI-1 and PCSK9 to regulate metabolic markers. METHODS: Observational and longitudinal study of 190 patients with obesity and obesity-related comorbidities who underwent bariatric surgery. We measured, before and after bariatric surgery, the anthropometric variables and we performed biochemical analysis by standard methods (glucose, insulin, triglycerides [TG], total cholesterol, high-density lipoprotein cholesterol [HDL-C], low-density lipoprotein cholesterol [LDL-C] and TG/HDL-C ratio, PAI-1 and PCSK9 were measured by ELISA). RESULTS: PAI-1 levels decreased significantly after bariatric surgery, and were positively correlated with lipids, glucose, and TG, with significance on PCSK9 and TG/HDL-C alleviating the insulin resistance (IR) and inducing a state reversal of type 2 diabetes (T2D) with a significant decrease in body weight and BMI (p <0.0001). Multivariate regression analysis predicted a functional model in which PAI-1 acts as a regulator of PCSK9 (p <0.002), TG (p <0.05), and BMI; at the same time, PCSK9 modulates LDL-C HDL-C and PAI-1. CONCLUSIONS: After bariatric surgery, we found a positive association and crosstalk between PAI-1 and PCSK9, which modulates the delicate balance of cholesterol, favoring the decrease of circulating lipids, TG, and PAI-1, which influences the glucose levels with amelioration of IR and T2D, demonstrating the crosstalk between fibrinolysis and lipid metabolism, the two main factors involved in atherosclerosis and cardiovascular disease in human obesity.


Assuntos
Cirurgia Bariátrica , Obesidade , Inibidor 1 de Ativador de Plasminogênio , Pró-Proteína Convertase 9 , Humanos , Inibidor 1 de Ativador de Plasminogênio/sangue , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Pró-Proteína Convertase 9/sangue , Pró-Proteína Convertase 9/metabolismo , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Obesidade/cirurgia , Obesidade/metabolismo , Obesidade/sangue , Estudos Longitudinais , Resistência à Insulina , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/cirurgia , Triglicerídeos/sangue , Triglicerídeos/metabolismo
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