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1.
Neurogastroenterol Motil ; 30(9): e13361, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29745434

RESUMO

BACKGROUND: Needleless transcutaneous electroacupuncture (TEA) improves nausea and myoelectrical activity in diabetic gastroparesis (GP). Synchronized TEA (STEA), which combines synchronized breathing with TEA, is more potent than TEA in enhancing vagal activity in healthy subjects. AIMS: To investigate whether STEA improves symptoms, electrogastrogram (EGG) and vagal activity in idiopathic gastroparesis (IGP). METHODS: Eighteen IGP subjects underwent 2 randomized visits (sham at non-acupoints or real STEA at acupoints) consisted of a 30-minute baseline, an Ensure challenge to provoke nausea, followed by 60-minute treatment with sham or real STEA, and 15-minute observation period. Severity of nausea, EGG, and vagal activity (based on electrocardiogram and serum Pancreatic Polypeptide, PP) were recorded. RESULTS: In sham or STEA, the nausea scores of 2.7 ± 0.5 and 1.9 ± 0.5 at fasting baseline, respectively, increased to 5.9 ± 0.4 and 5.8 ± 0.3 during Ensure test (P < .05, vs baseline), subsequently reduced to 3.4 ± 0.6 with sham or 3.6 ± 0.6 with STEA, respectively (P < .05, vs Ensure period). Experiments with sham and STEA started with similar % of normal waves on EGG (66.4 ± 3.9 and 61.8 ± 3.0, respectively); decreased to 63. 5 ± 4.1 and 58.2 ± 2.8 during the Ensure test. After STEA, there was ~24% increase in % of normal waves, significantly different from the sham (6.0%) (P < .01). In sham or STEA, vagal activity was identical at baseline and after the Ensure. STEA induced a 3-fold increase in vagal activity compared with sham (P < .01). Ensure increased serum PP levels, and both treatments decreased the PP CONCLUSIONS: In IGP, STEA is not superior to Sham in decreasing nausea, but is more effective in improving gastric dysrhythmia.


Assuntos
Exercícios Respiratórios/métodos , Eletroacupuntura/métodos , Gastroparesia/terapia , Adulto , Idoso , Feminino , Motilidade Gastrointestinal , Gastroparesia/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/etiologia , Adulto Jovem
2.
Neurogastroenterol Motil ; 30(11): e13350, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29687525

RESUMO

BACKGROUND: Direct diagnosis of small intestinal bacterial overgrowth (SIBO) requires the collection and culture of fluid from the jejunal lumen, with a finding of over 105 viable bacteria per mL. More often, SIBO is diagnosed indirectly, using a non-invasive test of the exhaled hydrogen and methane generated by microbial fermentation when ingested glucose reaches the jejunum. Our objective was to determine how well this breath test detects chronic overgrowth of jejunal bacteria that is unrelated to gastrointestinal surgery. METHODS: Eighteen patients reporting symptoms consistent with SIBO received a glucose breath test. On a later day, the jejunal lumen was sampled via aspiration during enteroscopy. Jejunal aspirates were cultured on aerobic and anaerobic media. DNA was extracted from the same samples and analyzed by quantitative pan-bacterial PCR amplification of 16S ribosomal rRNA genes, which provided a culture-independent bacterial cell count. KEY RESULTS: Combined bacterial colony counts ranged from 5.7 x 103 to 7.9 x 106 CFU/mL. DNA-based yields ranged from 1.5 x 105 to 3.1 x 107 bacterial genomes per mL. Microbial viability ranged from 0.3% to near 100%. We found no significant correlation of glucose breath test results with either the number of bacterial colonies or with the DNA-based bacterial cell counts. Instead, higher signals in the hydrogen-methane breath test were significantly correlated with a lower viability of jejunal bacteria, at a P-value of .014. CONCLUSIONS & INFERENCES: The glucose-based hydrogen and methane breath test is not sensitive to the overgrowth of jejunal bacteria. However, a positive breath test may indicate altered jejunal function and microbial dysbiosis.


Assuntos
Infecções Bacterianas/diagnóstico , Testes Respiratórios/métodos , Enteropatias/diagnóstico , Enteropatias/microbiologia , Jejuno/microbiologia , Adulto , Idoso , Feminino , Glucose/análise , Humanos , Hidrogênio/análise , Masculino , Metano/análise , Pessoa de Meia-Idade
3.
Artigo em Inglês | MEDLINE | ID: mdl-28851005

RESUMO

BACKGROUND & AIMS: Increases in mucosal immune cells have frequently been observed in irritable bowel syndrome (IBS) patients. However, this finding is not completely consistent between studies, possibly due to a combination of methodological variability, population differences and small sample sizes. We performed a meta-analysis of case-control studies that compared immune cell counts in colonic biopsies of IBS patients and controls. METHODS: PubMed and Embase were searched in February 2017. Results were pooled using standardized mean difference (SMD) and were considered significant when zero was not within the 95% confidence interval (CI). Heterogeneity was assessed based on I2 statistics where I2  ≤ 50% and I2  > 50% indicated fixed and random effect models, respectively. KEY RESULTS: Twenty-two studies on 706 IBS patients and 401 controls were included. Mast cells were increased in the rectosigmoid (SMD: 0.38 [95% CI: 0.06-0.71]; P = .02) and descending colon (SMD: 1.69 [95% CI: 0.65-2.73]; P = .001) of IBS patients. Increased mast cells were observed in both constipation (IBS-C) and diarrhea predominant IBS (IBS-D). CD3+ T cells were increased in the rectosigmoid (SMD: 0.53 [95% CI: 0.21-0.85]; P = .001) and the descending colon of the IBS patients (SMD: 0.79, 95% CI [0.28-1.30]; P = .002). This was possibly in relation to higher CD4+ T cells in IBS (SMD: 0.33 [95% CI: 0.01-0.65]; P = .04) as there were no differences in CD8+ T cells. CONCLUSIONS & INFERENCES: Mast cells and CD3+ T cells are increased in colonic biopsies of patients with IBS vs non-inflamed controls. These changes are segmental and sometimes IBS-subtype dependent. The diagnostic value of the quantification of colonic mucosal cells in IBS requires further investigation.


Assuntos
Colo/imunologia , Síndrome do Intestino Irritável/imunologia , Complexo CD3/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Humanos , Mastócitos/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-28872760

RESUMO

BACKGROUND: Wireless motility capsule (WMC) findings are incompletely defined in suspected gastroparesis. We aimed to characterize regional WMC transit and contractility in relation to scintigraphy, etiology, and symptoms in patients undergoing gastric emptying testing. METHODS: A total of 209 patients with gastroparesis symptoms at NIDDK Gastroparesis Consortium centers underwent gastric scintigraphy and WMCs on separate days to measure regional transit and contractility. Validated questionnaires quantified symptoms. KEY RESULTS: Solid scintigraphy and liquid scintigraphy were delayed in 68.8% and 34.8% of patients; WMC gastric emptying times (GET) were delayed in 40.3% and showed 52.8% agreement with scintigraphy; 15.5% and 33.5% had delayed small bowel (SBTT) and colon transit (CTT) times. Transit was delayed in ≥2 regions in 23.3%. Rapid transit was rarely observed. Diabetics had slower GET but more rapid SBTT versus idiopathics (P ≤ .02). GET delays related to greater scintigraphic retention, slower SBTT, and fewer gastric contractions (P ≤ .04). Overall gastroparesis symptoms and nausea/vomiting, early satiety/fullness, bloating/distention, and upper abdominal pain subscores showed no relation to WMC transit. Upper and lower abdominal pain scores (P ≤ .03) were greater with increased colon contractions. Constipation correlated with slower CTT and higher colon contractions (P = .03). Diarrhea scores were higher with delayed SBTT and CTT (P ≤ .04). CONCLUSIONS & INFERENCES: Wireless motility capsules define gastric emptying delays similar but not identical to scintigraphy that are more severe in diabetics and relate to reduced gastric contractility. Extragastric transit delays occur in >40% with suspected gastroparesis. Gastroparesis symptoms show little association with WMC profiles, although lower symptoms relate to small bowel or colon abnormalities.


Assuntos
Endoscopia por Cápsula/métodos , Esvaziamento Gástrico , Gastroparesia/diagnóstico por imagem , Cintilografia , Endoscopia por Cápsula/instrumentação , Feminino , Gastroparesia/fisiopatologia , Humanos , Masculino , Pressão , Estudos Prospectivos
5.
Artigo em Inglês | MEDLINE | ID: mdl-28066953

RESUMO

BACKGROUND: Animal studies have increasingly highlighted the role of macrophages in the development of delayed gastric emptying. However, their role in the pathophysiology of human gastroparesis is unclear. Our aim was to determine changes in macrophages and other cell types in the gastric antrum muscularis propria of patients with diabetic and idiopathic gastroparesis. METHODS: Full thickness gastric antrum biopsies were obtained from patients enrolled in the Gastroparesis Clinical Research Consortium (11 diabetic, 6 idiopathic) and 5 controls. Immunolabeling and quantitative assessment was done for interstitial cells of Cajal (ICC) (Kit), enteric nerves protein gene product 9.5, neuronal nitric oxide synthase, vasoactive intestinal peptide, substance P, tyrosine hydroxylase), overall immune cells (CD45) and anti-inflammatory macrophages (CD206). Gastric emptying was assessed using nuclear medicine scintigraphy and symptom severity using the Gastroparesis Cardinal Symptom Index. RESULTS: Both diabetic and idiopathic gastroparesis patients showed loss of ICC as compared to controls (Mean [standard error of mean]/hpf: diabetic, 2.28 [0.16]; idiopathic, 2.53 [0.47]; controls, 6.05 [0.62]; P=.004). Overall immune cell population (CD45) was unchanged but there was a loss of anti-inflammatory macrophages (CD206) in circular muscle (diabetic, 3.87 [0.32]; idiopathic, 4.16 [0.52]; controls, 6.59 [1.09]; P=.04) and myenteric plexus (diabetic, 3.83 [0.27]; idiopathic, 3.59 [0.68]; controls, 7.46 [0.51]; P=.004). There was correlation between the number of ICC and CD206-positive cells (r=.55, P=.008). Enteric nerves (PGP9.5) were unchanged: diabetic, 33.64 (3.45); idiopathic, 41.26 (6.40); controls, 46.80 (6.04). CONCLUSION: Loss of antral CD206-positive anti-inflammatory macrophages is a key feature in human gastroparesis and it is associates with ICC loss.


Assuntos
Complicações do Diabetes/metabolismo , Gastroparesia/metabolismo , Lectinas Tipo C/metabolismo , Macrófagos/metabolismo , Lectinas de Ligação a Manose/metabolismo , Antro Pilórico/metabolismo , Receptores de Superfície Celular/metabolismo , Adulto , Complicações do Diabetes/patologia , Sistema Nervoso Entérico/metabolismo , Feminino , Fibrose , Gastroparesia/patologia , Humanos , Células Intersticiais de Cajal/metabolismo , Células Intersticiais de Cajal/patologia , Masculino , Receptor de Manose , Pessoa de Meia-Idade , Antro Pilórico/patologia , Adulto Jovem
6.
Artigo em Inglês | MEDLINE | ID: mdl-27781342

RESUMO

BACKGROUND: Early satiety (ES) and postprandial fullness (PPF) are often present in gastroparesis, but the importance of these symptoms in gastroparesis has not been well-described. The aims were: (i) Characterize ES and PPF in patients with gastroparesis. (ii) Assess relationships of ES and PPF with etiology of gastroparesis, quality of life, body weight, gastric emptying, and water load testing. METHODS: Gastroparetic patients filled out questionnaires assessing symptoms (PAGI-SYM) and quality of life (PAGI-QOL, SF-36v2). Patients underwent gastric emptying scintigraphy and water load testing. KEY RESULTS: 198 patients with gastroparesis (134 IG, 64 DG) were evaluated. Early satiety was severe or very severe in 50% of patients. Postprandial fullness was severe or very severe in 60% of patients. Severity scores for ES and PPF were similar between idiopathic and diabetic gastroparesis. Increasing severity of ES and PPF were associated with other gastroparesis symptoms including nausea/vomiting, satiety/early fullness, bloating, and upper abdominal pain and GERD subscores. Increasing severity of ES and PPF were associated with increasing gastroparesis severity, decreased BMI, decreased quality of life from PAGI-QOL and SF-36 physical health. Increasing severity of ES and PPF were associated with increasing gastric retention of a solid meal and decreased volume during water load test. CONCLUSIONS & INFERENCES: Early satiety and PPF are commonly severe symptoms in both diabetic and idiopathic gastroparesis. Early satiety and PPF severity are associated with other gastroparesis symptom severities, body weight, quality of life, gastric emptying, and water load testing. Thus, ES and PPF are important symptoms characterizing gastroparesis. ClinicalTrials.gov number: NCT NCT01696747.


Assuntos
Ingestão de Líquidos/fisiologia , Esvaziamento Gástrico/fisiologia , Gastroparesia/fisiopatologia , Período Pós-Prandial/fisiologia , Resposta de Saciedade/fisiologia , Índice de Gravidade de Doença , Adulto , Feminino , Gastroparesia/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sistema de Registros
7.
Neurogastroenterol Motil ; 28(12): 1902-1914, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27350152

RESUMO

BACKGROUND: Nausea and vomiting are classic symptoms of gastroparesis. It remains unclear if characteristics of nausea and vomiting are similar in different etiologies of gastroparesis. The aims of this article were as follows: to describe characteristics of nausea and vomiting in patients with gastroparesis and to determine if there are differences in nausea and vomiting in diabetic (DG) and idiopathic gastroparesis (IG). METHODS: Gastroparetic patients enrolling in the NIDDK Gastroparesis Registry underwent assessment with history and questionnaires assessing symptoms, quality of life, and a questionnaire characterizing nausea and vomiting. KEY RESULTS: Of 159 gastroparesis patients (107 IG, 52 DG), 96% experienced nausea, whereas 65% experienced vomiting. Nausea was predominant symptom in 28% and vomiting was predominant in 4%. Nausea was severe or very severe in 41%. PAGI-SYM nausea/vomiting subscore was greater with increased vomiting severity, but not nausea severity in DG than IG. Nausea was related to meals in 71%; lasting most of the day in 41%. Increasing nausea severity was related to decreased quality of life. Nausea often preceded vomiting in 82% of patients and vomiting often relieved nausea in 30%. Vomiting was more common in DG (81%) compared to IG (57%; p = 0.004). Diabetic patients more often had vomiting in the morning before eating, during the night, and when not eating. CONCLUSIONS & INFERENCES: Nausea is present in essentially all patients with gastroparesis irrespective of cause and associated with decreased quality of life. In contrast, vomiting was more prevalent, more severe, and occurred more often in DG than IG. Thus, characteristics of vomiting differ in IG vs DG.


Assuntos
Diabetes Mellitus/fisiopatologia , Gastroparesia/fisiopatologia , Náusea/fisiopatologia , Vômito/fisiopatologia , Adulto , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Feminino , Esvaziamento Gástrico/fisiologia , Gastroparesia/diagnóstico , Gastroparesia/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/diagnóstico , Náusea/epidemiologia , Estudos Prospectivos , Sistema de Registros , Inquéritos e Questionários , Vômito/diagnóstico , Vômito/epidemiologia
8.
Neurogastroenterol Motil ; 28(7): 1048-54, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26940535

RESUMO

BACKGROUND: Depletion and ultrastructural changes of interstitial cells of Cajal (ICC) in the gastric body and antrum have been observed in gastroparesis. This research was performed to investigate the ICC population in the muscularis propria and fibrosis of the muscular layer of the pylorus in gastroparesis. METHODS: Full thickness pyloric and antral biopsies were obtained from 17 gastroparetic and 6 non-gastroparetic controls. Biopsies were stained with C-Kit for ICC and Trichrome for collagen fibrosis. Interstitial cells of Cajal depletion in the antrum was defined as mean ICC count <10 per 20 high power fields (HPF) based on established data. KEY RESULTS: The average pyloric ICC count was ≥10/HPF in the control patients. Twelve (70.5%) gastroparetic patients had pyloric ICC loss. Only five patients (29.4%) had ICC loss in the antrum. Gastric emptying (GE) was not significantly different in patients with depleted vs normal pyloric ICC. However, GE at 2 h was slower in patients with antral ICC <10/HPF compared to those with normal antral ICC populations. Collagen fibrosis was observed in the pylorus of 14 (82.3%) patients. Inclusion bodies in the muscularis propria of the pylorus were identified in four patients, all with diabetic gastroparesis. CONCLUSIONS & INFERENCES: In gastroparetic patients, ICC loss in the pylorus is twice as common as in the antrum and fibrosis in the pyloric smooth muscle is nearly three times more common than the antrum. These findings can provide one explanation for pyloric dysfunction which is a contributing factor to the pathophysiology of gastroparesis.


Assuntos
Gastroparesia/patologia , Células Intersticiais de Cajal/patologia , Piloro/patologia , Adulto , Estudos de Casos e Controles , Feminino , Fibrose , Esvaziamento Gástrico/fisiologia , Gastroparesia/fisiopatologia , Humanos , Células Intersticiais de Cajal/fisiologia , Masculino , Pessoa de Meia-Idade , Músculo Liso/patologia , Músculo Liso/fisiologia , Piloro/fisiologia
9.
Neurogastroenterol Motil ; 28(7): 1001-15, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26946489

RESUMO

BACKGROUND: In studies of diabetic gastroparesis, patients with type 1 and type 2 diabetes mellitus (T1DM, T2DM) are often combined for analyses. We compared gastroparesis severity, healthcare utilization, psychological function, and quality of life in T1DM vs T2DM gastroparesis patients. METHODS: Questionnaire, laboratory, and scintigraphy data from patients with gastroparesis and T1DM and T2DM from seven centers of the National Institute of Diabetes and Digestive and Kidney Diseases Gastroparesis Clinical Research Consortium Registry were compared at enrollment and after 48 weeks. Multiple regression models assessed baseline and follow-up differences between diabetes subtypes. KEY RESULTS: At baseline, T1DM patients (N = 78) had slower gastric emptying, more hospitalizations, more gastric stimulator implantations, higher hemoglobin A1c (HbA1c), and more anxiety vs T2DM patients (N = 59). Independent discriminators of patients with T1DM vs T2DM included worse gastroesophageal reflux disease, less bloating, more peripheral neuropathy, and fewer comorbidities (p ≤ 0.05). On follow-up, gastrointestinal (GI) symptom scores decreased only in T2DM (p < 0.05), but not in T1DM patients who reported greater prokinetic, proton pump inhibitor, anxiolytic, and gastric stimulator usage over 48 weeks (p ≤ 0.03). Gastrointestinal symptoms at baseline and 48 weeks with both subtypes were not associated with HbA1c, peripheral neuropathy, psychological factors, or quality of life. CONCLUSIONS & INFERENCES: Baseline symptoms were similar in T1DM and T2DM patients, even though T1DM patients had worse gastric emptying delays and higher HbA1c suggesting other factors mediate symptom severity. Symptom scores at 48 weeks decreased in T2DM, but not T1DM patients, despite increased medical and surgical treatment utilization by T1DM patients. Defining causes of different outcomes in diabetic gastroparesis warrants further investigation.


Assuntos
Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Gastroparesia/diagnóstico , Gastroparesia/epidemiologia , Adulto , Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Seguimentos , Gastroparesia/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Sistema de Registros , Resultado do Tratamento
10.
Data Brief ; 6: 492-4, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26900594

RESUMO

In this article, we describe data on (1) compositions for both as-cast and heat treated specimens were summarized in Table 1; (2) the determined enthalpy of mixing of liquid phase is listed in Table 2; (3) thermodynamic database of the Co-Pr system in TDB format for the research articled entitle Chemical partitioning for the Co-Pr system: First-principles, experiments and energetic calculations to investigate the hard magnetic phase W.

11.
Phys Rev Lett ; 114(5): 057001, 2015 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-25699463

RESUMO

Inelastic neutron scattering is employed to investigate the impact of electronic nematic order on the magnetic spectra of LaFeAsO and Ba(Fe(0.953)Co(0.047))(2)As(2). These materials are ideal to study the paramagnetic-nematic state, since the nematic order, signaled by the tetragonal-to-orthorhombic transition at T(S), sets in well above the stripe antiferromagnetic ordering at T(N). We find that the temperature-dependent dynamic susceptibility displays an anomaly at T(S) followed by a sharp enhancement in the spin-spin correlation length, revealing a strong feedback effect of nematic order on the low-energy magnetic spectrum. Our findings can be consistently described by a model that attributes the structural or nematic transition to magnetic fluctuations, and unveils the key role played by nematic order in promoting the long-range stripe antiferromagnetic order in iron pnictides.

12.
Neurogastroenterol Motil ; 26(9): 1275-84, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25041465

RESUMO

BACKGROUND: There is increasing evidence for specific cellular changes in the stomach of patients with diabetic (DG) and idiopathic (IG) gastroparesis. The most significant findings are loss of interstitial cells of Cajal (ICC), neuronal abnormalities, and an immune cellular infiltrate. Studies done in diabetic mice have shown a cytoprotective effect of CD206+ M2 macrophages. To quantify overall immune cellular infiltrate, identify macrophage populations, and quantify CD206+ and iNOS+ cells. To investigate associations between cellular phenotypes and ICC. METHODS: Full thickness gastric body biopsies were obtained from non-diabetic controls (C), diabetic controls (DC), DG, and IG patients. Sections were labeled for CD45, CD206, Kit, iNOS, and putative human macrophage markers (HAM56, CD68, and EMR1). Immunoreactive cells were quantified from the circular muscle layer. KEY RESULTS: Significantly fewer ICC were detected in DG and IG tissues, but there were no differences in the numbers of cells immunoreactive for other markers between patient groups. There was a significant correlation between the number of CD206+ cells and ICC in DG and DC patients, but not in C and IG and a significant correlation between iNOS+ cells and ICC in the DC group, but not the other groups. CD68 and HAM56 reliably labeled the same cell populations, but EMR1 labeled other cell types. CONCLUSIONS & INFERENCES: Depletion of ICC and correlation with changes in CD206+ cell numbers in DC and DG patients suggests that in humans, like mice, CD206+ macrophages may play a cytoprotective role in diabetes. These findings may lead to novel therapeutic options, targeting alternatively activated macrophages.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Gastroparesia/patologia , Células Intersticiais de Cajal/patologia , Macrófagos/patologia , Estômago/patologia , Adulto , Contagem de Células , Feminino , Gastroparesia/etiologia , Gastroparesia/imunologia , Humanos , Lectinas Tipo C , Macrófagos/imunologia , Receptor de Manose , Lectinas de Ligação a Manose , Pessoa de Meia-Idade , Receptores de Superfície Celular , Estômago/imunologia
13.
Nat Commun ; 5: 3333, 2014 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-24566374

RESUMO

Large magnetic anisotropy and coercivity are key properties of functional magnetic materials and are generally associated with rare earth elements. Here we show an extreme, uniaxial magnetic anisotropy and the emergence of magnetic hysteresis in Li2(Li(1-x)Fe(x))N. An extrapolated, magnetic anisotropy field of 220 T and a coercivity field of over 11 T at 2 K outperform all known hard ferromagnets and single-molecular magnets. Steps in the hysteresis loops and relaxation phenomena in striking similarity to single-molecular magnets are particularly pronounced for x≪1 and indicate the presence of nanoscale magnetic centres. Quantum tunnelling, in the form of temperature-independent relaxation and coercivity, deviation from Arrhenius behaviour and blocking of the relaxation, dominates the magnetic properties up to 10 K. The simple crystal structure, the availability of large single crystals and the ability to vary the Fe concentration make Li2(Li(1-x)Fe(x))N an ideal model system to study macroscopic quantum effects at elevated temperatures and also a basis for novel functional magnetic materials.

14.
Neurogastroenterol Motil ; 25(10): 815-e636, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23895180

RESUMO

BACKGROUND: Gastric electrical stimulation (GES) is a therapeutic option for intractable symptoms of gastroparesis (GP). Idiopathic GP (ID-GP) represents a subset of GP. AIMS: A prospective, multicenter, double-blinded, randomized, crossover study to evaluate the safety and efficacy of Enterra GES in the treatment of chronic vomiting in ID-GP. METHODS: Thirty-two ID-GP subjects (mean age 39; 81% F, mean 7.7 years of GP) were implanted with GES. The stimulator was turned ON for 1½ months followed by double-blind randomization to consecutive 3-month crossover periods with the device either ON or OFF. ON stimulation was followed in unblinded fashion for another 4.5 months. Twenty-five subjects completed the crossover phase and 21 finished 1 year of follow-up. KEY RESULTS: During the unblinded ON period, there was a reduction in weekly vomiting frequency (WVF) from baseline (61.2%, P < 0.001). There was a non-significant reduction in WVF between ON vs OFF periods (the primary outcome) with median reduction of 17% (P > 0.10). Seventy-five percent of patients preferred the ON vs OFF period (P = 0.021). At 1 year, WVF remained decreased (median reduction = 87%, P < 0.001), accompanied by improvements in GP symptoms, gastric emptying and days of hospitalization (P < 0.05). CONCLUSIONS & INFERENCES: (i) In this prospective study of Enterra GES for ID-GP, there was a reduction in vomiting during the initial ON period; (ii) The double-blind 3-month periods showed a non-significant reduction in vomiting in the ON vs OFF period, the primary outcome variable; (iii) At 12 months with ON stimulation, there was a sustained decrease in vomiting and days of hospitalizations.


Assuntos
Terapia por Estimulação Elétrica/métodos , Gastroparesia/terapia , Vômito/terapia , Adulto , Estudos Cross-Over , Método Duplo-Cego , Eletrodos Implantados , Feminino , Gastroparesia/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Vômito/etiologia , Adulto Jovem
15.
Neurogastroenterol Motil ; 25(11): e705-17, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23848826

RESUMO

BACKGROUND: TZP-102, a potent, oral, ghrelin receptor agonist, improved diabetic gastroparesis symptoms in Phase 2a. METHODS: Patients with type 1 or 2 diabetes, delayed gastric half-emptying (T(1/2)), and ≥3 months gastroparesis symptoms randomized 1 : 1 : 1 to double-blind placebo, 10-mg, or 20-mg TZP-102 once daily for 12 weeks (Study TZP-102-CL-G003). Study TZP-102-CL-G004 patients randomized 1 : 1 to 10-mg TZP-102:placebo three-times-daily. Primary endpoint was change-from-baseline through Weeks 11-12 in Daily Diary of Gastroparesis Symptoms Questionnaire (GSDD) via electronic Patient Recorded Outcome device: worst severity of nausea, early satiety, bloating, and upper abdominal pain in 24 h (0 = none-to-5 = very severe). GSDD Composite Score for eligibility was ≥2.5 (Day-14-to-baseline). Patient Overall Treatment Evaluation (OTE) provided an anchor-based minimal clinically important difference (MCID) for GSDD Composite Score. KEY RESULTS: Study TZP-102-CL-G003 enrolled 201 outpatients: females 72%; Caucasians 87%; type 2 diabetes 61%; insulin-dependent 65%; age mean ± SD 53 ± 11.3 years; HbA1c 7.8 ± 1.5%; GCSI 3.4 ± 0.7; GSDD Composite 3.6 ± 0.6; gastric T1/2 131 ± 32 min; n = 69 (10-mg), n = 66 (20-mg), n = 66 (placebo). Primary endpoint (GSDD): significant improvement in all arms, although not for TZP-102 vs placebo: mean change-from-baseline -1.7, -1.4, -1.5 (10-mg, 20-mg, placebo); Gastroparesis Cardinal Symptom Index -1.8, -1.6, -1.5, respectively. The OTE (all patients) at Week-12 was: Patient 3.7 ± 3.2 and Physician 3.6 ± 3.0 with median score for both of 5.0 = important on scale of improvement; individual MCID was 1.61 and 0.94 for group analyses, greater than expected. Study TZP-102-CL-G004 with similar demographic/disease characteristics was prematurely terminated for efficacy futility (n = 64 with Week-4 assessments). CONCLUSIONS & INFERENCES: Efficacy of TZP-102 was not demonstrated compared with placebo in diabetic gastroparesis; however, there was substantial symptom improvement in all arms (ClinicalTrials.gov NCT01452815/NCT01664637).


Assuntos
Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Esvaziamento Gástrico/efeitos dos fármacos , Gastroparesia/tratamento farmacológico , Compostos Macrocíclicos/uso terapêutico , Receptores de Grelina/agonistas , Método Duplo-Cego , Feminino , Gastroparesia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade
16.
Neurogastroenterol Motil ; 25(5): 427-38, e300-1, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23414452

RESUMO

BACKGROUND: Factors associated with abdominal pain in gastroparesis are incompletely evaluated and comparisons of pain vs other symptoms are limited. This study related pain to clinical factors in gastroparesis and contrasted pain/discomfort- with nausea/vomiting-predominant disease. METHODS: Clinical and scintigraphy data were compared in 393 patients from seven centers of the NIDDK Gastroparesis Clinical Research Consortium with moderate-severe (Patient Assessment of Upper Gastrointestinal Disorders Symptoms [PAGI-SYM] score ≥ 3) vs none-mild (PAGI-SYM < 3) upper abdominal pain and predominant pain/discomfort vs nausea/vomiting. KEY RESULTS: Upper abdominal pain was moderate-severe in 261 (66%). Pain/discomfort was predominant in 81 (21%); nausea/vomiting was predominant in 172 (44%). Moderate-severe pain was more prevalent with idiopathic gastroparesis and with lack of infectious prodrome (P ≤ 0.05) and correlated with scores for nausea/vomiting, bloating, lower abdominal pain/discomfort, bowel disturbances, and opiate and antiemetic use (P < 0.05), but not gastric emptying or diabetic neuropathy or control. Gastroparesis severity, quality of life, and depression and anxiety were worse with moderate-severe pain (P ≤ 0.008). Factors associated with moderate-severe pain were similar in diabetic and idiopathic gastroparesis. Compared to predominant nausea/vomiting, predominant pain/discomfort was associated with impaired quality of life, greater opiate, and less antiemetic use (P < 0.01), but similar severity and gastric retention. CONCLUSIONS & INFERENCES: Moderate-severe abdominal pain is prevalent in gastroparesis, impairs quality of life, and is associated with idiopathic etiology, lack of infectious prodrome, and opiate use. Pain is predominant in one fifth of gastroparetics. Predominant pain has at least as great an impact on disease severity and quality of life as predominant nausea/vomiting.


Assuntos
Dor Abdominal/etiologia , Gastroparesia/complicações , Náusea/etiologia , Vômito/etiologia , Dor Abdominal/epidemiologia , Dor Abdominal/psicologia , Adulto , Feminino , Humanos , Masculino , Náusea/psicologia , Prevalência , Qualidade de Vida , Vômito/psicologia
17.
Neurogastroenterol Motil ; 25(2): e140-50, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23279217

RESUMO

BACKGROUND: Gastroparesis causes significant morbidity and treatment options are limited. TZP-102 a novel, macrocyclic, selective, oral ghrelin receptor agonist, was evaluated in a randomized, double-blind, placebo-controlled trial in patients with diabetic gastroparesis. METHODS: A total of 92 outpatients were randomized to once-daily administrations of 10-mg (n = 22), 20-mg (n = 21), 40-mg (n = 23) TZP-102 or placebo (n = 26). The primary endpoint was the change from baseline in gastric half-emptying time (T(½)) utilizing (13)C-breath test methodology and secondary endpoints included symptom improvement using patient-reported gastroparesis symptom scores (PAGI-SYM questionnaire) and patient and physician overall treatment evaluations (OTE). KEY RESULTS: Gastric T½ changes were not statistically significant between TZP-102 and placebo after 28 days of treatment at any dose. Clinical improvements (-1.0 to -1.4 point mean decrease in symptom severity) occurred in the Gastroparesis Cardinal Symptom Index (GCSI) component of the PAGI-SYM, which was significant vs placebo for all TZP-102 doses combined. Improvements became evident after 1 week of treatment. Significantly, more patients given TZP-102 (any dose) had a 50% reduction in baseline GCSI score (28.8%vs 7.7% placebo). Safety profiles were similar across groups. All TZP-102 doses were well-tolerated with no adverse cardiac, weight, or glucose control outcomes. CONCLUSIONS & INFERENCES: TZP-102 for 28 days, at doses of 10-40 mg once daily, was well-tolerated and resulted in a reduction in symptoms of gastroparesis. The lack of correlation between symptom improvement and gastric emptying change is consistent with previous studies in diabetic gastroparesis, and emphasizes the value of patient-defined outcomes in determining therapeutic benefit.


Assuntos
Complicações do Diabetes/tratamento farmacológico , Gastroparesia/tratamento farmacológico , Compostos Macrocíclicos/administração & dosagem , Receptores de Grelina/agonistas , Adulto , Idoso , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Esvaziamento Gástrico/efeitos dos fármacos , Gastroparesia/etiologia , Humanos , Compostos Macrocíclicos/efeitos adversos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
18.
Neurogastroenterol Motil ; 24(7): 639-45, e274, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22497770

RESUMO

BACKGROUND: Enterra gastric electrical stimulation (GES) is an alternative treatment for gastroparesis (GP) when standard medical therapy fails. The aims of this study were to evaluate the association between total symptom score (TSS) and reduction in gastric retention (GR) after GES by GP etiology and to examine the sensitivity of the association to varying cutpoints used to define GR and TSS improvement. METHODS: Gastric retention assessed with a standardized (99m) Tc radio-labeled egg meal and TSS measured by a five-point Likert scale in 221 GP patients treated with Enterra GES therapy for at least 1 year were analyzed. Bivariate chi-square test and multivariable logistic regression with all possible cutpoints were used to assess the consistency of association and quantitate the relationship across three GP etiologies. KEY RESULTS: Symptom relief in diabetic GP was more likely attributable to GR reduction as indicated by the consistently significant odds ratios (P < 0.01) across all cutpoints. The association in idiopathic GP was inconclusive because odds ratios were sensitive to cutpoints with P-values ranging from 0.01 to 0.47. No association was found for patients with post surgical gastroparesis (P > 0.1 for all cutpoints). Patient age, gender, baseline TSS and baseline GR had no significant effect at 5% level on clinical improvement regardless of cutpoints for GR. CONCLUSIONS & INFERENCES: Association between clinical improvements and GR reduction following GES treatment depends on patient etiology and was able to be demonstrated in diabetic GP. The association for idiopathic GP was inconclusive and no such association was found for post surgical GP across all possible cutpoint combinations.


Assuntos
Terapia por Estimulação Elétrica , Gastroparesia/fisiopatologia , Gastroparesia/terapia , Adolescente , Adulto , Idoso , Feminino , Esvaziamento Gástrico/fisiologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
19.
Neurogastroenterol Motil ; 24(6): 531-9, e249, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22339929

RESUMO

BACKGROUND: Cellular changes associated with diabetic (DG) and idiopathic gastroparesis (IG) have recently been described from patients enrolled in the Gastroparesis Clinical Research Consortium. The association of these cellular changes with gastroparesis symptoms and gastric emptying is unknown. The aim of this study was to relate cellular changes to symptoms and gastric emptying in patients with gastroparesis. METHODS: Earlier, using full thickness gastric body biopsies from 20 DG, 20 IG, and 20 matched controls, we found decreased interstitial cells of Cajal (ICC) and enteric nerves and an increase in immune cells in both DG and IG. Here, demographic, symptoms [gastroparesis cardinal symptom index score (GCSI)], and gastric emptying were related to cellular alterations using Pearson's correlation coefficients. KEY RESULTS: Interstitial cells of Cajal counts inversely correlated with 4 h gastric retention in DG but not in IG (r = -0.6, P = 0.008, DG, r = 0.2, P = 0.4, IG). There was also a significant correlation between loss of ICC and enteric nerves in DG but not in IG (r = 0.5, P = 0.03 for DG, r = 0.3, P = 0.16, IG). Idiopathic gastroparesis with a myenteric immune infiltrate scored higher on the average GCSI (3.6 ± 0.7 vs 2.7 ± 0.9, P = 0.05) and nausea score (3.8 ± 0.9 vs 2.6 ± 1.0, P = 0.02) as compared to those without an infiltrate. CONCLUSIONS & INFERENCES: In DG, loss of ICC is associated with delayed gastric emptying. Interstitial cells of Cajal or enteric nerve loss did not correlate with symptom severity. Overall clinical severity and nausea in IG is associated with a myenteric immune infiltrate. Thus, full thickness gastric biopsies can help define specific cellular abnormalities in gastroparesis, some of which are associated with physiological and clinical characteristics of gastroparesis.


Assuntos
Sistema Nervoso Entérico/patologia , Gastroparesia/patologia , Estômago/patologia , Adulto , Idoso , Sistema Nervoso Entérico/fisiopatologia , Feminino , Esvaziamento Gástrico/fisiologia , Gastroparesia/fisiopatologia , Humanos , Células Intersticiais de Cajal/patologia , Células Intersticiais de Cajal/fisiologia , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Estômago/fisiopatologia , Inquéritos e Questionários
20.
Aliment Pharmacol Ther ; 34(3): 263-73, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21668458

RESUMO

BACKGROUND: Cyclic vomiting syndrome is a disorder characterised by recurrent episodes of severe nausea and vomiting separated by symptom-free periods. AIMS: To review the history, epidemiology, clinical aspects, pathophysiology, diagnosis and treatments of adult cyclic vomiting syndrome as well as to identify areas for further clinical research and the unanswered questions in this field. METHODS: We conducted a PubMed search using such keywords as cyclic vomiting syndrome; nausea; vomiting; pathophysiology; diagnosis; treatment; trigger factors; gastric emptying test; autonomic nerve function test; gastrointestinal hormones; outcome and natural history and combined this information with the knowledge and extensive clinical research and publications from the authors. RESULTS: Available data show that in adult cyclic vomiting syndrome, severe epigastric and sometimes diffuse abdominal pain accompanies most cycles of nausea and vomiting interspersed with periods of symptomatic remission. Psychological disorders, specifically anxiety and depression are common, and gastric emptying is actually rapid in approximately 60% of patients and normal in the remainder. There is an impressive and sustained response to high-dose tricyclic antidepressants. In up to 15% who are regarded as poor responders to tricyclic antidepressants, a predictable profile can be identified related to co-existing psychological disorders, marijuana use, poorly controlled migraine headache or chronic narcotic use. CONCLUSIONS: Cyclic vomiting syndrome in adults is an entity that is being increasingly recognised, but the need to educate Internists, Gastroenterologists and Emergency Department staff remains an ongoing challenge.


Assuntos
Vômito , Adulto , Idade de Início , Humanos
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