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1.
Trends Ecol Evol ; 39(7): 677-688, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38508922

RESUMO

Although primarily studied through the lens of community ecology, phenomena consistent with priority effects appear to be widespread across many different scenarios spanning a broad range of spatial, temporal, and biological scales. However, communication between these research fields is inconsistent and has resulted in a fragmented co-citation landscape, likely due to the diversity of terms used to refer to priority effects across these fields. We review these related terms, and the biological contexts in which they are used, to facilitate greater cross-disciplinary cohesion in research on priority effects. In breaking down these semantic barriers, we aim to provide a framework to better understand the conditions and mechanisms of priority effects, and their consequences across spatial and temporal scales.


Assuntos
Ecologia , Ecologia/métodos , Biologia
2.
Int J Cosmet Sci ; 39(5): 556-563, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28699164

RESUMO

OBJECTIVE: Quaternary ammonium cationic surfactants (ACSs) and N-[3-alkyl(12,14)oxy-2-hydroxypropyl]-l-arginine hydrochloride (N-AOHPA) were used to emulsify silicone. The potential of the resulting emulsions in hair conditioning products was investigated. METHODS: The emulsions were prepared using a homogenizer and/or high-pressure homogenizer. ACSs and N-AOHPA were used as silicone emulsifiers. The stability of the emulsions was evaluated by measuring particle sizes, creaming fractions, polydispersity indexes and zeta potentials. Moreover, the N-AOHPA-stabilized emulsion was compared with the ACS-stabilized emulsion to evaluate the adsorption amount of silicone on healthy and bleached hair surfaces and the inhibitory effects on amino acid dissolution from bleached hair. The adsorption site of the N-AOHPA-stabilized emulsion was observed using a scanning electron microscope. RESULTS: For all surfactants, the silicone emulsions prepared using the high-pressure homogenizer were more stable than those prepared using the homogenizer. When N-AOHPA was used as the surfactant, the silicone emulsion was especially stable. Furthermore, the d50 value of the N-AOHPA-stabilized emulsion was smaller than that of the ACS-stabilized emulsion. The adsorption behaviour of the silicone droplets in the different emulsions varied depending on the nature of the surfactant and the preparation method. The amount of ACS-stabilized silicone adsorbed on healthy hair was higher than that adsorbed on bleached hair, especially when the emulsion was prepared using the homogenizer. In contrast, the amount of N-AOHPA-stabilized silicone adsorbed on bleached hair was high, and no differences were observed between the N-AOHPA-stabilized emulsions prepared using the homogenizer and high-pressure homogenizer. The emulsified droplets, especially the N-AOHPA-stabilized droplets prepared using the high-pressure homogenizer, prevented amino acid dissolution from bleached hair. It was concluded that the silicone droplet adsorption site affected the dissolution process because the small N-AOHPA-stabilized droplets adsorbed at cuticle edges. CONCLUSION: This study shows that N-AOHPA has good potential for use as an emulsifier in products used for improving the condition of damaged hair.


Assuntos
Aminoácidos/química , Preparações para Cabelo , Compostos de Amônio Quaternário/química , Silicones/química , Tensoativos/química , Adsorção , Cátions , Emulsões
3.
Clin Exp Obstet Gynecol ; 44(1): 61-64, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29714867

RESUMO

PURPOSE OF INVESTIGATION: This study aimed to estimate the effectiveness of hysteroscopic myomectomy for symptomatic submucous uterine fibroids and to identify prognostic factors for persistent or recurrent symptoms. MATERIALS AND METHODS: A total of 237 patients who underwent hysteroscopic myomectomy were divided into three groups according to the classification of the European Society for Gynaecological Endoscopy: Type 0 (n=116), Type I (n=97), and Type II (n=24). Medical records and videotape records of all patients were retrospectively reviewed. RESULTS: Improvement of symptoms was achieved in 100% of Types 0 and I, and 66.7% of Type II. The five-year cumulative symptom-free rates after hysteroscopic myomectomy were 96.7% ± 1.9%, 87.8% 6.7%, and 44.5% ± 12.7% in Types 0, I, and II, respectively. The mean symptom-free periods were 46.2 ± 2.6, 47.7 ± 2.7, and 24.7 ± 6.3 months in Types 0, I, and II, respectively. Logistic regression analysis showed that co-existence of other myomas and Type II were independent prognostic factors for recurrence of symptoms. CONCLUSION: Type I fibroids are a good indication for hysteroscopic myomectomy. In Type II, some patients feel that their symptoms improve, but this curative effect could be temporary.


Assuntos
Histeroscopia , Leiomioma/cirurgia , Miomectomia Uterina , Neoplasias Uterinas/cirurgia , Adulto , Feminino , Seguimentos , Humanos , Leiomioma/classificação , Estudos Retrospectivos , Neoplasias Uterinas/classificação
4.
Clin Exp Obstet Gynecol ; 44(1): 113-115, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29714878

RESUMO

The aim of this analysis was to investigate the onset time and significance of maximum volume of polyhydraminios and whether the tter was associated with causes. This was a retrospective cohort study between 2012 and 2014. A total number of 68 singleton pregancies were analyzed. Gestational age at onset of polyhydramnios was 30.0 ± 2.8 (25-36) weeks in maternal factor, 30.0 ± 3.5 (25- 7) weeks in fetal factor, and 32.3 ± 2.0 (27-37) weeks in idiopathic factor. Median of maximum amniotic fluid index (AFI) was gnificantly late onset in idiopathic factor. Diabetes, gestational or pre-existing, was present in all of women (ten cases) in maternal facror. Higher AFI was found to be associated with an increased frequency of prenatally detected congenital anomalies. Abnormal fetal kary- type noted in 18/45 (40%) cases of polyhydramnios. Polyhydramnios diagnosed on ultrasound requires further maternal and fetal iagnostic tests.


Assuntos
Poli-Hidrâmnios/etiologia , Adulto , Líquido Amniótico , Estudos de Coortes , Anormalidades Congênitas , Transtornos de Deglutição/complicações , Complicações do Diabetes , Feminino , Idade Gestacional , Humanos , Obstrução Intestinal/complicações , Gravidez , Estudos Retrospectivos
5.
Clin Exp Obstet Gynecol ; 44(2): 236-238, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29746029

RESUMO

This was a retrospective cohort study between 2002 and 2011. A total number of 150 singleton pregnancies with preterm premature rupture of membranes (PROM) (before 34 weeks) were analyzed. Histological chorioamnionitis (Blanc grade III) was significantly increased over three days from onset of premature rupture of membranes. The positive relationship was strengthened (odds ratios, 3.5; 95% confidence intervals, 1.5-5.2) over three days from onset of preterm PROM. PROM is a risk factor important for histological chorioamnionitis. To avoid neonatal infection, early termination is recommended in preterm PROM patients.


Assuntos
Corioamnionite , Ruptura Prematura de Membranas Fetais , Adulto , Corioamnionite/epidemiologia , Corioamnionite/patologia , Feminino , Ruptura Prematura de Membranas Fetais/epidemiologia , Ruptura Prematura de Membranas Fetais/patologia , Idade Gestacional , Humanos , Recém-Nascido , Japão/epidemiologia , Masculino , Gravidez , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/etiologia , Prevalência , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
6.
Eur J Gynaecol Oncol ; 38(1): 150-152, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29767887

RESUMO

Retroperitoneal leiomyosarcoma is a relatively rare and aggressive tumor. Because of its rarity, it is difficult to arrive at a definite diagnosis preoperatively and to design an effective strategy. Here the authors report a case of peritoneal leiomyosarcoma in which diagnosis was difficult because the clinical course resembled that of ovarian cancer. A 77-year-old woman diagnosed with ovarian cancer underwent laparotomy. The excised tumor contained a necrotic polypoid mass that histologically displayed the features of leiomyosarcoma. The patient received adjuvant chemotherapy with a combination of gemcitabine and docetaxel but died two months after surgery owing to the aggressive behavior of the tumor. Because the preoperative diagnosis in this case was ovarian cancer, arriving at a treatment strategy assuming peritoneal leiomyosarcoma was difficult. If complete surgical resection of tumor is not performed, as in the present case, the prognosis can be extremely poor.


Assuntos
Leiomiossarcoma/diagnóstico , Neoplasias Ovarianas/diagnóstico , Neoplasias Retroperitoneais/diagnóstico , Idoso , Feminino , Humanos , Leiomiossarcoma/cirurgia , Neoplasias Ovarianas/cirurgia , Neoplasias Retroperitoneais/cirurgia
7.
Eur J Gynaecol Oncol ; 38(1): 153-156, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29767888

RESUMO

The authors here report a 54-year-old (gravida 0, para 0), who claimed to have had her menarche at age 13 and menopause at 52 years. Two months prior to presentation, the subject first noticed a hard but elastic fist-sized mass in the left inguinal region that gradually grew, causing pressure-related pain. Although the external genitalia appeared female, the vagina was short and blind-ending, and no uterus or ovaries were identified on transvaginal ultrasound. Chromosome banding results (G-band method) showed 46XY. Laparoscopy revealed no traces of a vestigial uterus or ovaries; thus, based on the appearance of the external genitalia, a diagnosis of testicular feminization syndrome was made. Pathological testing of the palpable mass led to a diagnosis of seminoma with Leydig cell hyperplasia. Thus, in this case, the development of a seminoma in an undescended testis led to the detection of testicular feminization syndrome.


Assuntos
Síndrome de Resistência a Andrógenos/diagnóstico , Seminoma/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Seminoma/cirurgia
8.
Clin Exp Obstet Gynecol ; 43(6): 800-802, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29944226

RESUMO

The present authors analyzed patients' backgrounds and pre-surgical findings to clarify the risk factors of rupture of fallopian tubal pregnancy. The surgical findings 113 cases were clearly diagnosed as fallopian tubal pregnancy with or without rupture. Twenty-six cases of fallopian tubal pregnancy were ruptured and 87 cases were not ruptured at the time of operation. The risk factors of fallopian tubal rupture were assessed by Chi-square for independence test and multiple regression analysis. Obesity (BMI over 26), prior birth history, social welfare entitlement, ultrasonography findings of fetal heart movement, and pre-surgical serum beta-hCG level more than 3,000 mIU/ml patient were significantly higher risk in fallopian tubal rupture. Fertility treatment patient were at significantly lower risk for fallopian tubal rupture. Higher beta-hCG levels, especially >3,000 mIU/ml is associated with increased risk of fallopian tubal rupture in ectopic pregnancy.


Assuntos
Doenças das Tubas Uterinas/cirurgia , Gravidez Tubária/cirurgia , Técnicas de Reprodução Assistida/estatística & dados numéricos , Adulto , Fatores Etários , Gonadotropina Coriônica Humana Subunidade beta/sangue , Doenças das Tubas Uterinas/epidemiologia , Tubas Uterinas/cirurgia , Feminino , Humanos , Modelos Logísticos , Análise Multivariada , Paridade , Gravidez , Gravidez Tubária/sangue , Gravidez Tubária/epidemiologia , Fatores de Risco , Ruptura Espontânea , Adulto Jovem
9.
J Chem Phys ; 143(4): 044509, 2015 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-26233147

RESUMO

A first sharp diffraction peak (FSDP) is observed in the X-ray total structure factor of a molten mixture of RbCl-AgCl, while both pure melts of RbCl and AgCl do not exhibit FSDP individually. Molecular dynamics simulations were performed to investigate the origin of the FSDP with the polarizable ion model (PIM). Coexistence of covalent Ag-Cl and ionic Rb-Cl bonds leads the system to evolve intermediate range ordering, which is simulated by introducing the induced polarization in different ways between Ag-Cl with fully polarizable treatment based on Vashishta-Raman potential and Rb-Cl with suppression over-polarization in the nearest neighbor contribution based on Born-Meyer potential. The partial structure factors for both the Ag-Ag and Rb-Rb correlations, SAgAg(Q) and SRbRb(Q), show a positive contribution to the FSDP, while SAgRb(Q) for the Ag-Rb correlation exhibits a negative contribution, indicating that Ag and Rb ions are distributed in an alternating manner within the intermediate-range length scale. The origin of the intermediate-range chemical ordering of cations can be ascribed to the preferred direction of the dipole moments of anions in the PIM.


Assuntos
Cloretos/química , Modelos Químicos , Rubídio/química , Compostos de Prata/química , Ânions/química , Cátions/química , Simulação de Dinâmica Molecular , Temperatura
10.
Rev Sci Instrum ; 85(2): 02A705, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24593439

RESUMO

High intensity laser-plasma interaction has attracted considerable interest for a number of years. The laser-plasma interaction is accompanied by generation of various charged particle beams, such as high-energy proton and ions with high charge to mass ratio (Q/M; same as multi-charged ions). Results of simultaneous novel measurements of electron-induced photonuclear neutrons (photoneutron), which are a diagnostic of the laser-plasma interaction, are proposed to use for optimization of the laser-plasma ion generation. The proposed method is demonstrated by the laser irradiation with the intensity of 1 × 10(21) W/cm(2) on the metal foil target. The photoneutrons are measured by using NE213 liquid scintillation detectors. Heavy-ion signal is registered with the CR-39 track detector simultaneously. The measured signals of the electron-induced photoneutrons are well reproduced by using the Particle and Heavy Ion Transport code System. The results obtained provide useful approach for analyzing the various laser based ion beams.

11.
Rev Sci Instrum ; 85(2): 02B904, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24593609

RESUMO

Experimental demonstration of multi-charged heavy ion acceleration from the interaction between the ultra-intense short pulse laser system and the metal target is presented. Al ions are accelerated up to 12 MeV/u (324 MeV total energy). To our knowledge, this is far the highest energy ever reported for the case of acceleration of the heavy ions produced by the <10 J laser energy of 200 TW class Ti:sapphire laser system. Adding to that, thanks to the extraordinary high intensity laser field of ∼10(21) W cm(-2), the accelerated ions are almost fully stripped, having high charge to mass ratio (Q/M).


Assuntos
Alumínio , Íons Pesados , Lasers , Aceleradores de Partículas/instrumentação
12.
J Dev Orig Health Dis ; 4(3): 239-48, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25054843

RESUMO

Intrauterine growth-restricted (IUGR) offspring are at increased risk of adult obesity, as a result of changes in energy balance mechanisms. We hypothesized that impairment of hypothalamic insulin signaling contributes to hyperphagia in IUGR offspring. Study pregnant dams were 50% food restricted from days 10 to 21 to create IUGR newborns. At 5 weeks of age, food intake was measured following intracerebroventricular (icv) injection of vehicle or insulin (10 mU) in control and IUGR pups. At 6 weeks of age, with pups in fed or fasted (48 h) states, pups received icv vehicle or insulin after which they were decapitated, and hypothalamic arcuate (ARC) nucleus dissected for RNA and protein expression. IUGR rats consumed more food than controls under basal conditions, consistent with upregulated ARC phospho AMP-activated protein kinase (pAMPK) and neuropeptide Y (NPY). Insulin acutely reduced food intake in both control and IUGR rats. Consistent with anorexigenic stimulation, central insulin decreased AMP-activated protein kinase and NPY mRNA expression and increased proopiomelanocortin mRNA expression and pAkt, with significantly reduced responses in IUGR as compared with controls. Despite feeding, IUGR offspring exhibit a persistent state of orexigenic stimulation in the ARC nucleus and relative resistance to the anorexigenic effects of icv insulin. These results suggest that impaired insulin signaling contributes to hyperphagia and obesity in IUGR offspring.

13.
Pharmazie ; 67(12): 1018-25, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23346767

RESUMO

The information on the stability of medications is important to secure their quality. There is, however, little information about the stability of medications which assume to be kept by patients and customers. We previously showed that a delay in drug release occurs in some over-the-counter (OTC) drugs following storage in a high temperature, high humidity environment. In this study we prepared model tablet formulations containing an active ingredient and excipients to investigate the cause of this delayed release. The results reveal that delayed release occurs in preparations compounded with acetaminophen (AA) as the active ingredient and erythritol (ET) and crospovidone (CP) as excipients. In addition, ET deliquesces in a high humidity environment, then incorporates other particles during room temperature storage to form an aggregate. SEM observations and micropore distribution measurements conducted on OTC tablets that exhibit delayed release revealed that the number of intraparticle pores decreased after storage under high temperature, high humidity conditions. Thus, the delayed release by these pharmaceutical product formulations may be due to a change in the micropore structure both on the surface and within the particles, thereby decreasing the solvent infiltration pathways leading to the interior of the preparation.


Assuntos
Acetaminofen/análise , Analgésicos não Narcóticos/análise , Química Farmacêutica , Preparações de Ação Retardada , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Excipientes , Umidade , Microscopia Eletrônica de Varredura , Microscopia de Polarização , Medicamentos sem Prescrição/análise , Solubilidade , Comprimidos , Temperatura
15.
Neuroradiol J ; 24(5): 699-711, 2011 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-24059764

RESUMO

Spontaneous intradural vertebral artery dissections may cause subarachnoid hemorrhage and often result in devastating damage. Increased use of noninvasive imaging studies has allowed larger numbers of patients to be diagnosed. In addition, intracranial vertebral artery dissection tends to induce multiple lesions affecting both intracranial vertebral arteries recurrently. Although unruptured dissections in this area usually have a benign nature, some authors have reported on the incidence of rupture from this lesion. Once hemorrhage from a dissecting vessel wall has occurred, it needs to be treated in the acute phase because of the high risk of rebleeding resulting in high morbidity and mortality. From December 2004 to July 2010, we managed 47 patients with spontaneous vertebral artery dissection, 31 patients were ruptured and 16 were unruptured. All patients who suffered from subarachnoid hemorrhage were treated with endovascular procedures. Most of the patients with unruptured dissection received medical therapy, but if the aneurysmal dilatation persisted or grew, surgical interventions were performed. Stenting with or without coils was deployed for 13 patients with posterior inferior cerebellar artery involvement at the site of dissection and/or were affected on the dominant side. In some patients, stenting was performed even if they were in the acute phase. For other ruptured patients, internal coil trappings were performed. Six patients died due to severe initial subarachnoid hemorrhage and one patient, who underwent stent deployment with coils for the dominant vertebral artery, with bilateral dissection continuing to the basilar artery died due to rerupture while the next additional coiling was planning. There were two cases of complications related to the intervention. During the follow-up period no bleeding occurred in any of the patients except for the previously mentioned patient. In conclusion, internal coil trapping or stent placement with or without coils was effective in preventing rebleeding of ruptured vertebral artery dissection. If the dissection is unruptured, it is necessary to detect the risk of bleeding with careful watching and when progress appears to be made, patients should be treated promptly. Stent-assisted therapy for preserving the patency of the parent artery and major branches is a promising treatment for vertebral artery dissection, even in the acute stage of subarachnoid hemorrhage. However, the risk of acute rerupture and recurrence remains even with the porous stent placement with or without coils.

16.
Kyobu Geka ; 63(12): 1090-3, 2010 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-21066855

RESUMO

We report a resected case of thymoma with a solitary pulmonary metastasis. A 63-year-old woman had pointed out a solitary nodule in right lung field on chest X-ray. Computed tomography (CT) scan showed an anterior mediastinal tumor and a solitary lung nodule in the right lower lobe. Extended thymectomy and partial resection of right lung was performed. Pathological diagnosis showed an invasive thymoma (type B3) and a pulmonary metastasis. Post operative radiotherapy was administered and she is doing well 19 months following the resection. Thymoma with a solitary synclonous pulmonary metastasis is rare and is classified into Masaoka stage IVb. Generally, thymoma cases with distant metastasis are not indication for operation. But, if radical resection is possible, operation is recommended for good prognosis.


Assuntos
Neoplasias Pulmonares/secundário , Timoma/patologia , Neoplasias do Timo/patologia , Feminino , Humanos , Pessoa de Meia-Idade
17.
Pharmazie ; 65(5): 379-83, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20503933

RESUMO

Food contains components that may either increase or decrease the bioavailability of a drug. In particular, it is known that grapefruit juice and St. John's Wort induce drug interactions via an effect on the drug-metabolizing enzyme cytochrome P450 (CYP). However, interactions with membrane transporters, such as P-glycoprotein and multidrug resistance-related protein (MRP), may also influence drug bioavailability. The objective of the present study was to investigate the effects of kaempferol, a flavonoid present in food, on the cytotoxicity of anticancer drugs and the mechanisms of drug resistance in the human glioblastoma cell line T98G. Acute exposure to kaempferol inhibited the efflux of calcein, a substrate of MRP; however, chronic exposure caused no apparent effect on calcein efflux. The cytotoxicity of doxorubicin was not influenced by chronic exposure of cells to kaempferol, although that of cisplatin was significantly reduced. Multidrug resistance is often associated with increased levels of MRP1, glutathione S-transferase (GST) and activity by chronic exposure to kaempferol, although MRP2 protein levels are decreased. Accordingly, we hypothesized that the cytotoxicity of anticancer drugs that conjugate with glutathione and the substrate of MRPs may be influenced by long-term intake of drugs such as kaempferol, which are substrates of MRPs and GST.


Assuntos
Antioxidantes/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Quempferóis/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/biossíntese , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/biossíntese , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/farmacologia , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fluoresceínas/farmacologia , Interações Alimento-Droga , Glutationa Transferase/biossíntese , Glutationa Transferase/metabolismo , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Humanos , Proteína 2 Associada à Farmacorresistência Múltipla , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Kyobu Geka ; 62(11): 1010-3, 2009 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-19827557

RESUMO

Situs inversus totalis represents a complete mirror image anatomy of the normal arrangement of the thoracic and abdominal viscera. This rare condition may pose possible surgical problems due to anatomical abnormality. There were few reports of surgical treatment for lung cancer patient with situs inversus totalis. In this case report, we describe a 74-year-old patient with situs inversus totalis and primary lung cancer who underwent successful left upper lobectomy and systemic lymph node dissection. For this rare condition, detail preoperative evaluation of mirror image anatomy with computed tomography and bronchofiber optic examination was thought to be a key to carry out safe operative procedure.


Assuntos
Neoplasias Pulmonares/complicações , Situs Inversus/complicações , Carcinoma de Pequenas Células do Pulmão/complicações , Idoso , Humanos , Masculino
19.
Pharmazie ; 64(6): 390-4, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19618676

RESUMO

We investigated the enhancement of the solubility of glimepiride (GLM), a poorly water soluble anti-diabetes drug, by cogrinding it with various cyclodextrins (CDs) using a ball mill. The phase solubility profiles of GLM with beta-CD and its derivatives were classified as A(L)-type, indicating the formation of a 1 : 1 stoichiometric water-soluble complex. When GLM crystals were coground with beta-CD using a ball mill for 48 h, the aqueous solubility of GLM increased to approximately 250 microg/mL. The powder X-ray diffraction pattern showed that the peak intensity of crystalline GLM decreased after cogrinding. Endothermic peaks of around 208 degrees C, which were assigned to the fusion of GLM crystals, disappeared in the DSC measurement of the ground mixture. After cogrinding, two sharp peaks assigned to sulfonylurea and benzoyl carbonyl stretching bands varied to broaden the peak to around 1700 cm(-1) in the C=O stretching region. These results suggested the formation of a complex between GLM and beta-CD during cogrinding.


Assuntos
Ciclodextrinas/química , Hipoglicemiantes/química , Compostos de Sulfonilureia/química , Varredura Diferencial de Calorimetria , Composição de Medicamentos , Excipientes , Indicadores e Reagentes , Solubilidade , Espectrofotometria Infravermelho , Difração de Raios X
20.
Oecologia ; 161(1): 1-14, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19412705

RESUMO

A growing body of evidence shows that aboveground and belowground communities and processes are intrinsically linked, and that feedbacks between these subsystems have important implications for community structure and ecosystem functioning. Almost all studies on this topic have been carried out from an empirical perspective and in specific ecological settings or contexts. Belowground interactions operate at different spatial and temporal scales. Due to the relatively low mobility and high survival of organisms in the soil, plants have longer lasting legacy effects belowground than aboveground. Our current challenge is to understand how aboveground-belowground biotic interactions operate across spatial and temporal scales, and how they depend on, as well as influence, the abiotic environment. Because empirical capacities are too limited to explore all possible combinations of interactions and environmental settings, we explore where and how they can be supported by theoretical approaches to develop testable predictions and to generalise empirical results. We review four key areas where a combined aboveground-belowground approach offers perspectives for enhancing ecological understanding, namely succession, agro-ecosystems, biological invasions and global change impacts on ecosystems. In plant succession, differences in scales between aboveground and belowground biota, as well as between species interactions and ecosystem processes, have important implications for the rate and direction of community change. Aboveground as well as belowground interactions either enhance or reduce rates of plant species replacement. Moreover, the outcomes of the interactions depend on abiotic conditions and plant life history characteristics, which may vary with successional position. We exemplify where translation of the current conceptual succession models into more predictive models can help targeting empirical studies and generalising their results. Then, we discuss how understanding succession may help to enhance managing arable crops, grasslands and invasive plants, as well as provide insights into the effects of global change on community re-organisation and ecosystem processes.


Assuntos
Agricultura , Ecossistema , Efeito Estufa , Modelos Biológicos , Desenvolvimento Vegetal , Microbiologia do Solo , Dinâmica Populacional , Especificidade da Espécie
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