RESUMO
Diagnosing chronic myeloid leukaemia (CML) during pregnancy is rare. Tyrosine kinase inhibitors (TKIs) have traditionally been contraindicated owing to their teratogenicity. Management decisions should consider the risks to mother and foetus of uncontrolled disease and teratogenic medications. Further cases are required to build upon the paucity of current literature. We report 22 cases of CML diagnosed during pregnancy from 2002 to date. Twenty-one pregnancies resulted in healthy babies and one patient miscarried. Some patients remained untreated throughout pregnancy but the majority received one or both of interferon-α and leucapheresis. One patient was started on imatinib at Week 26, and one on hydroxycarbamide in the third trimester. We report haematological parameters during pregnancy to provide clinicians with realistic expectations of management. There were no fetal abnormalities related to treatment during pregnancy. Seventeen patients achieved at least major molecular response on first-line TKI. A diagnosis of CML during pregnancy can be managed without significant consequences for mother or child. Leucapheresis and interferon-α are generally safe throughout pregnancy. Despite having been avoided previously, there is growing evidence that certain TKIs may be used in particular circumstances during the later stages of pregnancy. Future work should aim to further elucidate this safety profile.
RESUMO
This study uses NHS waiting times and osteoporosis medication community prescription datasets to assess the impact of COVID-19 on DXA waits and osteoporosis medication patterns in England. Results show significant increases in DXA waiting list times and variation in prescription rates. Investment is needed to improve waiting list times. PURPOSE: This study investigates the impact of COVID-19 on DXA scan waiting lists, service recovery and osteoporosis medication prescriptions in the NHS following the March 2020 national lockdowns and staff redeployment. METHODS: Data from March 2019 to June 2023, including NHS digital diagnostics waiting times (DM01) and osteoporosis medication prescriptions from the English Prescribing Dataset (EPD), were analysed. This encompassed total waiting list data across England's seven regions and prescribing patterns for various osteoporosis medications. Analyses included total activity figures and regression analysis to estimate expected activity without COVID-19, using R for all data analysis. RESULTS: In England, DXA waiting lists have grown significantly, with the yearly mean waiting list length increasing from 31,851 in 2019 to 65,757 in 2023. The percentage of patients waiting over 6 weeks for DXA scans rose from 0.9% in 2019 to 40% in 2020, and those waiting over 13 weeks increased from 0.1% in 2019 to 16.7% in 2020. Prescription trends varied, with increases in denosumab, ibandronic acid and risedronate sodium and decreases in alendronic acid, raloxifene hydrochloride and teriparatide. A notable overall prescription decrease occurred in the second quarter of 2020. CONCLUSION: COVID-19 has significantly increased DXA scan waiting lists with ongoing recovery challenges. There is a noticeable disparity in DXA service access across England. Osteoporosis care, indicated by medication prescriptions, also declined during the pandemic. Addressing these issues requires focused investment and effort to improve DXA scan waiting times and overall access to osteoporosis care in England.
Assuntos
Absorciometria de Fóton , Conservadores da Densidade Óssea , COVID-19 , Prescrições de Medicamentos , Osteoporose , Medicina Estatal , Listas de Espera , Humanos , Inglaterra/epidemiologia , COVID-19/epidemiologia , Absorciometria de Fóton/estatística & dados numéricos , Absorciometria de Fóton/métodos , Conservadores da Densidade Óssea/uso terapêutico , Osteoporose/tratamento farmacológico , Osteoporose/diagnóstico por imagem , Osteoporose/epidemiologia , Prescrições de Medicamentos/estatística & dados numéricos , Padrões de Prática Médica/tendências , Padrões de Prática Médica/estatística & dados numéricos , SARS-CoV-2 , Acessibilidade aos Serviços de Saúde/estatística & dados numéricosRESUMO
Substance use disorder prevention programs are most effective when matched appropriately to the baseline risk of the population. Individuals who misuse opioids often have unique risk profiles different from those who use other substances such as alcohol or cannabis. However, most substance use prevention programs are geared toward universal audiences, neglecting key inflection points along the continuum of care. The HEAL Prevention Cooperative (HPC) is a unique cohort of research projects that represents a continuum of care, from community-level universal prevention to indicated prevention among older adolescents and young adults who are currently misusing opioids or other substances. This paper describes the theoretical basis for addressing opioid misuse and opioid use disorder across the prevention continuum, using examples from research projects in the HPC.
Assuntos
Cannabis , Transtornos Relacionados ao Uso de Opioides , Uso Indevido de Medicamentos sob Prescrição , Adolescente , Adulto Jovem , Humanos , Transtornos Relacionados ao Uso de Opioides/prevenção & controle , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Analgésicos Opioides/uso terapêutico , Continuidade da Assistência ao PacienteRESUMO
BACKGROUND: Colorectal cancer remains a common cause of cancer death in the UK, with surgery being the mainstay of treatment. An objective measurement of the suitability of each patient for surgery, and their risk-benefit calculation, would be of great utility. We postulate that sarcopenia (low muscle mass) could fulfil this role as a prognostic indicator. The aim of this study was to determine the relationship between sarcopenia and long-term outcomes in patients undergoing elective bowel resection for colorectal cancer. METHODS: One hundred and sixty-three consecutive patients who had elective curative colorectal resection for cancer were eligible for inclusion in the study. Psoas muscle mass was assessed on preoperative computed tomography scan at the level of the L3 vertebra and standardised for patient height (total psoas index, TPI). Sarcopenia (low muscle mass) was defined as < 524 mm2/m2 in males and 385 mm2/m2 in females. In addition to clinical-pathological parameters, postoperative complications were recorded and patients were followed up for mortality for 1 year after surgery. RESULTS: Sarcopenia was present in 19.6% of the study participants and was significantly related to body mass index (p = 0.007), 30-day mortality (p = 0.042) and 1-year mortality (p = 0.046). In univariate analysis, American Society of Anesthesiologists grade (p = 0.016), tumour stage (p = 0.018) and sarcopenia (p = 0.043) were found to be significant independent predictors of 1-year mortality. CONCLUSIONS: This study has found sarcopenia to be prevalent in patients with colorectal cancer having elective surgery. Independent of age, sarcopenia was associated with poorer 30-day mortality and survival at 1 year. Measurement of muscle mass preoperatively could be used to stratify a patient's risk, allowing targeted strategies such as prehabilitation, to be implemented to modify sarcopenia and improve long-term outcomes for patients.
Assuntos
Colectomia/efeitos adversos , Neoplasias Colorretais/cirurgia , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Complicações Pós-Operatórias/mortalidade , Protectomia/efeitos adversos , Sarcopenia/mortalidade , Idoso , Índice de Massa Corporal , Colectomia/métodos , Neoplasias Colorretais/fisiopatologia , Procedimentos Cirúrgicos Eletivos/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Complicações Pós-Operatórias/etiologia , Protectomia/métodos , Prognóstico , Fatores de Risco , Sarcopenia/etiologia , Taxa de Sobrevida , Fatores de TempoRESUMO
OBJECTIVES: Colorectal polyp cancers present clinicians with a treatment dilemma. Decisions regarding whether to offer segmental resection or endoscopic surveillance are often taken without reference to good quality evidence. The aim of this study was to develop a treatment algorithm for patients with screen-detected polyp cancers. DESIGN: This national cohort study included all patients with a polyp cancer identified through the Scottish Bowel Screening Programme between 2000 and 2012. Multivariate regression analysis was used to assess the impact of clinical, endoscopic and pathological variables on the rate of adverse events (residual tumour in patients undergoing segmental resection or cancer-related death or disease recurrence in any patient). These data were used to develop a clinically relevant treatment algorithm. RESULTS: 485 patients with polyp cancers were included. 186/485 (38%) underwent segmental resection and residual tumour was identified in 41/186 (22%). The only factor associated with an increased risk of residual tumour in the bowel wall was incomplete excision of the original polyp (OR 5.61, p=0.001), while only lymphovascular invasion was associated with an increased risk of lymph node metastases (OR 5.95, p=0.002). When patients undergoing segmental resection or endoscopic surveillance were considered together, the risk of adverse events was significantly higher in patients with incomplete excision (OR 10.23, p<0.001) or lymphovascular invasion (OR 2.65, p=0.023). CONCLUSION: A policy of surveillance is adequate for the majority of patients with screen-detected colorectal polyp cancers. Consideration of segmental resection should be reserved for those with incomplete excision or evidence of lymphovascular invasion.
Assuntos
Algoritmos , Pólipos do Colo/patologia , Pólipos do Colo/cirurgia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Recidiva Local de Neoplasia/diagnóstico , Conduta Expectante , Idoso , Vasos Sanguíneos/patologia , Colectomia , Colonoscopia , Intervalo Livre de Doença , Detecção Precoce de Câncer , Medicina Baseada em Evidências , Feminino , Humanos , Metástase Linfática , Vasos Linfáticos/patologia , Masculino , Invasividade Neoplásica , Neoplasia Residual , Fatores de Risco , Escócia , Taxa de SobrevidaRESUMO
Synchrotron radiation spectromicroscopy provides a combination of submicron spatial resolution and chemical sensitivity that is well-suited to analysis of heterogeneous nuclear materials. The chemical and physical characteristics determined by scanning transmission X-ray microscopy (STXM) are complementary to information obtained from standard radiochemical analysis methods. In addition, microscopic quantities of radioactive material can be characterized rapidly by STXM with minimal sample handling and intrusion, especially in the case of particulate materials. The STXM can accommodate a diverse range of samples including wet materials, complex mixtures, and small quantities of material contained in a larger matrix. In these cases, the inventory of species present in a sample is likely to carry information on its process history; STXM has the demonstrated capability to identify contaminants and sample matrices. Operating in the soft X-ray regime provides particular sensitivity to the chemical state of specimens containing low-Z materials, via the K-edges of light elements. Here, recent developments in forensics-themed spectromicroscopy, sample preparation, and data acquisition methods at the Molecular Environmental Science Beamline 11.0.2 of the Advanced Light Source are described. Results from several initial studies are presented, demonstrating the capability to identify the distribution of the species present in heterogeneous uranium-bearing materials. Future opportunities for STXM forensic studies and potential methodology development are discussed.
RESUMO
BACKGROUND: Exercise in the preoperative period, or prehabilitation, continues to evolve as an important tool in optimising patients awaiting major intra-abdominal surgery. It has been shown to reduce rates of post-operative morbidity and length of hospital stay. The mechanism by which this is achieved remains poorly understood. Adaptations in mesenteric flow in response to exercise may play a role in improving post-operative recovery by reducing rates of ileus and anastomotic leak. AIMS: To systematically review the existing literature to clarify the impact of exercise on mesenteric arterial blood flow using Doppler ultrasound. METHODS: PubMed, EMBASE and the Cochrane library were systematically searched to identify clinical trials using Doppler ultrasound to investigate the effect of exercise on flow through the superior mesenteric artery (SMA). Data were extracted including participant characteristics, frequency, intensity, timing and type of exercise and the effect on SMA flow. The quality of each study was assessed using the Downs and Black checklist. RESULTS: Sixteen studies, comprising 305 participants in total, were included. Methodological quality was generally poor. Healthy volunteers were used in twelve studies. SMA flow was found to be reduced in response to exercise in twelve studies, increased in one and unchanged in two studies. Clinical heterogeneity precluded a meta-analysis. CONCLUSION: The weight of evidence suggests that superior mesenteric arterial flow is reduced immediately following exercise. Differences in frequency, intensity, timing and type of exercise make a consensus difficult. Further studies are warranted to provide a definitive understanding of the impact of exercise on mesenteric flow.
Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/reabilitação , Terapia por Exercício/métodos , Exercício Físico/fisiologia , Artérias Mesentéricas/diagnóstico por imagem , Circulação Esplâncnica/fisiologia , Abdome/cirurgia , Adulto , Idoso , Fístula Anastomótica/etiologia , Fístula Anastomótica/prevenção & controle , Ensaios Clínicos como Assunto , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Ecocardiografia Doppler/métodos , Feminino , Humanos , Íleus/etiologia , Íleus/prevenção & controle , Masculino , Artérias Mesentéricas/fisiologia , Pessoa de Meia-Idade , Período Pré-Operatório , Resultado do Tratamento , Adulto JovemRESUMO
We present new magnetic heat capacity and neutron scattering results for two magnetically frustrated molybdate pyrochlores: S=1 oxide Lu_{2}Mo_{2}O_{7} and S=1/2 oxynitride Lu_{2}Mo_{2}O_{5}N_{2}. Lu_{2}Mo_{2}O_{7} undergoes a transition to an unconventional spin glass ground state at T_{f}â¼16 K. However, the preparation of the corresponding oxynitride tunes the nature of the ground state from spin glass to quantum spin liquid. The comparison of the static and dynamic spin correlations within the oxide and oxynitride phases presented here reveals the crucial role played by quantum fluctuations in the selection of a ground state. Furthermore, we estimate an upper limit for a gap in the spin excitation spectrum of the quantum spin liquid state of the oxynitride of Δâ¼0.05 meV or Δ/|θ|â¼0.004, in units of its antiferromagnetic Weiss constant θâ¼-121 K.
RESUMO
The capability to predict size, composition, and transport of nuclear fallout enables public officials to determine immediate and prolonged guidance in the event of a nuclear incident. Predictive computer models of fallout can also provide useful insight for nuclear forensic response when detailed radiochemical processes can be reliably included. Current post-detonation nuclear fallout models prescribe particle size distributions empirically or semi-empirically, based on measurements across limited conditions pertaining to tests conducted primarily in Nevada and the Pacific. These empirical fallout relationships may be subject to large uncertainties in particle size and radionuclide activity distribution if used to extrapolate to other regions with different environmental conditions (e.g., urbanized areas). Replacing empirical relationships with physics-based microphysical process modeling can enable significant advances in the fidelity of predictive models simulating distributions of fallout across diverse environments. Particle microphysics describes the formation and evolution of fallout particles, as well as the interaction of radioactive material with entrained particles, which requires accounting for fundamental processes such as nucleation, condensation, and coagulation. The objective of this perspective article is to summarize computational techniques to simulate particle microphysical processes advancing the fidelity of predicting nuclear fallout. We review current empirical models for simulating post-detonation fallout and assess promising research directions moving towards physics-based predictive systems.
RESUMO
OBJECTIVE: To compare the impact of the prototype prolapse mesh Gynemesh PS with that of two new-generation lower stiffness meshes, UltraPro and SmartMesh, on vaginal morphology and structural composition. DESIGN: A mechanistic study employing a nonhuman primate model. SETTING: Magee-Womens Research Institute at the University of Pittsburgh. POPULATION: Parous rhesus macaques, with similar age, weight, parity and Pelvic Organ Prolapse-Questionnaire scores. METHODS: Following Institutional Animal Care Use Committee approval, 50 rhesus macaques were implanted with Gynemesh PS (n = 12), UltraPro with its blue line perpendicular to the longitudinal axis of vagina (n = 10), UltraPro with its blue line parallel to the longitudinal axis of vagina (n = 8) or SmartMesh (n = 8) via sacrocolpopexy following hysterectomy. Sham-operated animals (n = 12) served as controls. MAIN OUTCOME MEASURES: The mesh-vagina complex was removed after 12 weeks and analysed for histomorphology, in situ cell apoptosis, total collagen, elastin, glycosaminoglycan content and total collagenase activity. Appropriate statistics and correlation analyses were performed accordingly. RESULTS: Relative to sham and the two lower stiffness meshes, Gynemesh PS had the greatest negative impact on vaginal histomorphology and composition. Compared with sham, implantation with Gynemesh PS caused substantial thinning of the smooth muscle layer (1557 ± 499 µm versus 866 ± 210 µm, P = 0.02), increased apoptosis particularly in the area of the mesh fibres (P = 0.01), decreased collagen and elastin content (20%, P = 0.03 and 43%, P = 0.02, respectively) and increased total collagenase activity (135%, P = 0.01). Glycosaminoglycan, a marker of tissue injury, was highest with Gynemesh PS compared with sham and other meshes (P = 0.01). CONCLUSION: Mesh implantation with the stiffer mesh Gynemesh PS induced a maladaptive remodelling response consistent with vaginal degeneration.
Assuntos
Procedimentos Cirúrgicos em Ginecologia/instrumentação , Telas Cirúrgicas/efeitos adversos , Vagina/patologia , Animais , Apoptose , Biomarcadores/metabolismo , Colágeno/metabolismo , Colagenases/metabolismo , Elastina/metabolismo , Feminino , Glicosaminoglicanos/metabolismo , Marcação In Situ das Extremidades Cortadas , Macaca mulatta , Polipropilenos , Vagina/metabolismo , Vagina/cirurgiaRESUMO
The use of broad bandwidth lasers with automated feedback control of wavelength was applied to the measurement of (235)U/(238)U ratios by resonance ionization mass spectrometry (RIMS) to decrease laser-induced isotopic fractionation. By broadening the bandwidth of the first laser in a three-color, three-photon ionization process from a bandwidth of 1.8 GHz to about 10 GHz, the variation in sequential relative isotope abundance measurements decreased from 10% to less than 0.5%. This procedure was demonstrated for the direct interrogation of uranium oxide targets with essentially no sample preparation.
RESUMO
STUDY DESIGN: Cross-sectional. OBJECTIVE: To determine the association between leisure-time physical activity (LTPA) and adherence to Eating Well with Canada's Food Guide (CFG) in community-dwelling adults with chronic Spinal Cord Injury (SCI). SETTING: Ontario, Canada. METHODS: Participants were recruited as part of the Study of Health and Activity in People with SCI (SHAPE-SCI). Dietary data were collected using 24-h recalls and analysed for adherence to CFG recommendations by age group and gender. LTPA was assessed using the Physical Activity Recall Assessment for Persons with SCI. Statistical analysis comprised correlations, multiple regression and χ(2). RESULTS: We studied 75 adults (n=61 M; 42.4±11.8 years; 25.5±5.2 kg m(-2)) with chronic (≥1-year post-injury) SCI. Of these, 37% of participants were inactive, 29% were low-active and 33% were high-active. Fewer than 5% of participants were 100% adherent with CFG; 85% were adherent to ≤50%. Activity level and overall adherence to CFG were not correlated (r=-0.052, P=0.666). Although there were no associations between LTPA and vegetables and fruit, grain products, milk and alternatives, or other foods (all P>0.05), high activity was associated with consuming less than the minimum number of recommended servings of meat and alternatives (φ=-0.258, P=0.026). CONCLUSION: Clinicians need to be aware of the poor diet quality, and low levels of physical activity, of people with chronic SCI. They should not assume that those who are more active consume better quality diets than those who are low active or inactive. SPONSORSHIP: Canadian Institutes of Health Research.
Assuntos
Atividades Cotidianas/psicologia , Comportamento Alimentar/psicologia , Atividades de Lazer/psicologia , Traumatismos da Medula Espinal/dietoterapia , Traumatismos da Medula Espinal/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Estudos Transversais , Feminino , Fidelidade a Diretrizes/tendências , Inquéritos Epidemiológicos , Humanos , Vida Independente/psicologia , Masculino , Pessoa de Meia-Idade , Ontário/epidemiologia , Traumatismos da Medula Espinal/psicologia , Adulto JovemRESUMO
AIMS: The incidence of anal squamous cell cancer (SCCA) is rising. Although chemoradiotherapy (CRT) provides a chance of cure, a proportion of patients have an incomplete response or develop recurrence. This study assessed the value of inflammation-based prognostic indicators, including the modified Glasgow Prognostic Score (mGPS) and neutrophil:lymphocyte ratio (NLR), in patients with SCCA treated by CRT with curative intent. MATERIAL AND METHODS: Patients with histologically confirmed SCCA were identified from pathology records. Medical records were retrospectively reviewed and clinical, pathological and treatment characteristics were abstracted. The mGPS (0 = normal C-reactive protein [CRP] and albumin, 1 = CRP >10 mg/l and 2 = CRP >10 mg/l and albumin <35 mg/l) and NLR were calculated from routine blood tests obtained prior to CRT. RESULTS: In total, 118 patients underwent CRT for SCCA between December 2007 and February 2018. Of these, 99 patients had appropriate pretreatment blood results available. Systemic inflammation as indicated by NLR >3 and mGPS >0 was present in 41% and 39% of patients, respectively. Most patients had T2 or larger tumours (n = 85, 86%) without nodal involvement (n = 64, 65%). An elevated mGPS was associated with more advanced T-stage (56% versus 35%, P = 0.036). NLR >5 was associated with nodal positivity (56% versus 31%, P = 0.047). On multivariate analysis, more advanced T-stage (odds ratio 7.49, 95% confidence interval 1.51-37.20, P = 0.014) and a raised mGPS (odds ratio 5.13, 95% confidence interval 1.25-21.14, P = 0.024) were independently related to incomplete CRT response. An elevated mGPS was prognostic of inferior survival (hazard ratio 3.09, 95% confidence interval 1.47-6.50, P = 0.003) and cancer-specific survival (hazard ratio 4.32, 95% confidence interval 1.54-12.15, P = 0.006), independent of TNM stage. CONCLUSION: Systemic inflammation, as measured by the mGPS, is associated with an incomplete CRT response and is independently prognostic of inferior survival in patients with SCCA. The mGPS may offer a simple marker of inferior outcome that could be used to identify high-risk patients.
Assuntos
Neoplasias do Ânus , Carcinoma de Células Escamosas , Quimiorradioterapia/métodos , Inflamação/sangue , Linfócitos , Neutrófilos , Neoplasias do Ânus/imunologia , Neoplasias do Ânus/patologia , Neoplasias do Ânus/terapia , Proteína C-Reativa/análise , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Feminino , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Análise de SobrevidaRESUMO
Rabbits are born with a limited VDJ gene repertoire formed primarily by rearrangement of one VH gene, VH1. The VDJ genes are undiversified at birth but become diversified by approximately 2 mo of age. To investigate more closely the time during which this diversity occurs, we determined the nucleotide sequences of VDJ genes from peripheral blood leukocytes taken from young rabbits at various time points, and we examined the extent of the diversification of the VDJ genes. At 4 wk of age there were, on average, 3 nucleotide changes per VH region, with approximately 75% of the genes showing some diversification. The number of nucleotide changes per VH region increased to 12 by 6-8 wk of age, and all but 1 of the 35 sequences analyzed were diversified. Because only a limited number of genes can be examined by nucleotide sequence analysis, we used an RNase protection assay to examine a large number of genes and we determined the level of undiversified VH1 mRNA in lymphoid organs of both young and adult rabbits. In young rabbits, we found a high level of undiversified VDJ genes, but the level was greatly reduced by 2 mo of age. By adulthood, essentially all VDJ genes of cells from appendix, peripheral blood, and bone marrow were diversified. Because we had expected B lymphopoiesis to be ongoing in the bone marrow of adult rabbits, we were surprised not to find undiversified VDJ genes from the newly generated B cells. Therefore, we searched for evidence of ongoing B lymphopoiesis in bone marrow by isolating and examining circular DNA for the presence of VD and DJ recombination signal joints. We found highly reduced levels of recombination signal joints in bone marrow of adult rabbits relative to the levels found in bone marrow of newborn rabbits. These data indicate that limited VD and DJ gene rearrangements occur in bone marrow of adult rabbits, and we therefore suggest that B lymphopoiesis is limited in adults.
Assuntos
Envelhecimento/imunologia , Linfócitos B/imunologia , Rearranjo Gênico , Genes de Imunoglobulinas , Variação Genética , Hematopoese/imunologia , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Animais , Sequência de Bases , Clonagem Molecular , Primers do DNA , DNA Circular , Dados de Sequência Molecular , Mutação , Reação em Cadeia da Polimerase , CoelhosRESUMO
Using high resolution neutron diffraction and capacitance dilatometry we show that the thermal evolution of the helimagnetic state in CoMnSi is accompanied by a change in interatomic distances of up to 2%, the largest ever found in a metallic magnet. Our results and the picture of competing exchange and strongly anisotropic thermal expansion that we use to understand them sheds light on a new mechanism for large magnetoelastic effects that does not require large spin-orbit coupling.
RESUMO
Intraportal islet transplantation has shown initial promise for the treatment of type 1 diabetes. However, the portal vein site is associated with complications such as thrombosis and hepatic steatosis, leading to transplant failure. The aims of this study were to (1) test the feasibility of an alternative islet transplantation method that utilises a FDA-approved gelatin sponge as a novel islet carrier and (2) assess if exogenous addition of nerve growth factor (NGF) has any additional beneficial effects on graft performance in diabetic mice. Mice were rendered diabetic by a single intraperitoneal injection of streptozotocin. Five hundred syngeneic islets were seeded onto a Gelitaspon((R)) disc in the presence or absence of NGF, and placed into a silicone chamber surrounding the femoral neurovascular pedicle. Islet function was assessed by weekly monitoring of blood glucose levels and an intraperitoneal glucose tolerance test performed at the end of the study. Chambers were harvested for further histological analysis. Four of five mice transplanted with islets seeded onto Gelitaspon with NGF showed a significant reduction in blood glucose levels by 4 weeks after transplantation, and demonstrated a response similar to non-diabetic mice when tested with an intraperitoneal glucose tolerance test. Chamber tissue from this group contained islets with insulin-producing beta cells adjacent to the vascular pedicle. Islets seeded onto Gelitaspon with NGF and sited on femoral vessels using a tissue-engineering chamber offer an alternative method for islet transplantation in diabetic mice. This may have potential as a method for clinical islet transplantation.
Assuntos
Diabetes Mellitus Experimental/cirurgia , Hiperglicemia/tratamento farmacológico , Transplante das Ilhotas Pancreáticas/métodos , Fator de Crescimento Neural/uso terapêutico , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Teste de Tolerância a Glucose , CamundongosRESUMO
The crystal structure of a hydrothermally synthesized leucite analogue Cs(2)CuSi(5)O(12) has been determined and refined using the Rietveld method from high-resolution synchrotron X-ray and neutron powder diffraction data. This structure is based on the topology and cation-ordering scheme of the Pbca leucite structure of Cs(2)CdSi(5)O(12), and exhibits five ordered Si sites and one ordered Cu tetrahedrally coordinated (T) site. This structure for Cs(2)CuSi(5)O(12) is topologically identical to other known leucite structures and is different from that originally proposed by Heinrich & Baerlocher [(1991), Acta Cryst. C47, 237-241] in the tetragonal space group P4(1)2(1)2. The crystal structure of a dry-synthesized leucite analogue Cs(2)CuSi(5)O(12) has also been refined; this has the Ia3d cubic pollucite structure with disordered T sites.
RESUMO
BACKGROUND: Anastomotic leak (AL) is a significant complication of gastrointestinal (GI) surgery. Impaired perfusion of the anastomosis is thought to play an important role. The degree of aortic calcification (AC) visible on preoperative CT imaging may be associated with an increased risk of AL following GI resection. This review assessed the relationship between AC and AL in patients undergoing GI resection. MATERIALS AND METHODS: MEDLINE, EMBASE and the Cochrane library were systematically searched between 1946 and 2019. Relevant keywords were grouped to form a sensitive search strategy: surgical procedure (e.g. digestive system surgical procedure), calcification (e.g. vascular calcification, calcium score) and outcome (e.g. anastomotic leak). Studies assessing the degree of AC on preoperative imaging in relation to AL in adult patients requiring resection and anastomosis were included. The quality of each study was assessed using the Newcastle-Ottawa scale. Bias was assessed using the RevMan risk of bias tool. RESULTS: Nine observational studies were included: four in patients undergoing oesophageal resection (n = 1446) and five in patients undergoing colorectal resection (n = 556). AL occurred in 20% of patients following oesophagectomy and 14% of patients following colorectal resection. Adjustment for relevant confounders was limited in most studies. Two studies reported a relationship between the degree of AC and AL in patients undergoing oesophagectomy, independent of age and comorbidity. One study reported an association between AC and AL following colorectal resection, while three studies reported higher calcium scores in the iliac arteries of patients who developed colorectal AL. Overall study quality was moderate to good using the Newcastle-Ottawa scale. Detection and reporting bias was evident in the studies examining AL following colorectal resection. CONCLUSION: The current evidence suggests that the degree of AC may be associated with the development of AL, in particular in patients undergoing oesophagectomy. Further prospective data with adequate adjustment for confounders are required. PROSPERO REGISTRATION NUMBER: CRD42018081128.
Assuntos
Fístula Anastomótica/etiologia , Doenças da Aorta/etiologia , Esofagectomia/efeitos adversos , Complicações Pós-Operatórias/etiologia , Calcificação Vascular/etiologia , Adulto , Anastomose Cirúrgica/efeitos adversos , Colectomia/efeitos adversos , Feminino , Trato Gastrointestinal/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Observacionais como AssuntoRESUMO
Neutron powder diffraction has been used to observe the changes in hydrogen bonding that occur as a function of temperature in ND4IO3 and, thus, determine the structural features that occur during the low-temperature (103â K) phase transition. It is shown that in the deuterated material the change is not a phase change per se but rather a structural reorganization in which the hydrogen bonding becomes firmly locked in at the phase transition temperature, and stays in this configuration upon further cooling to 4.2â K. In addition, both the differences and changes in the axial thermal expansion coefficients in the region 100-290â K can be explained by the changes involving both the hydrogen bonding and the secondary I...O halogen bonds.
RESUMO
Peptides from the e14a2 BCR-ABL junction will elicit T-cell responses in vitro. Here, 19 imatinib treated CML patients in first chronic phase were vaccinated with BCR-ABL peptides spanning the e14a2 fusion junction, some of which were linked to the pan DR epitope PADRE to augment CD4+ T cell help. Six vaccinations were given over 9 weeks, together with sargramostim. All patients developed mild local reactions. T cell responses to PADRE were seen in all patients. Fourteen of 19 patients developed T cell responses to BCR-ABL peptides. The development of an anti-BCR-ABL T cell response correlated with a subsequent fall in BCR-ABL transcripts. No molecular benefit was seen in the 5 patients not in major cytogenetic response (MCR) at baseline. However, of the 14 patients in MCR at baseline, 13 developed at least 1 log fall in BCR-ABL transcripts, though this occurred several months after completing vaccination, consistent with an effect at a primitive CML stem cell level. Vaccination may improve the fall in BCR-ABL transcripts in patients who have received imatinib for more than 12 months. BCR-ABL peptide vaccination may improve control of CML, especially in patients responding well to imatinib. Randomised trials are required to address this further.