Mucosal Blood Research Articles

Biomarkers of Colorectal Cancer Risk Decrease 6\xa0months After Roux-en-Y Gastric Bypass Surgery

PurposeThe impact of weight loss on obesity-related colorectal cancer (CRC) risk is not well defined. Previous studies have suggested that Roux-en-Y gastric bypass (RYGB) surgery may have an unexpected adverse impact on CRC risk. This study aimed to investigate the impact of RYGB on biomarkers of CRC risk.Materials and methodsRectal mucosal biopsies and blood were obtained from patients undergoing RYGB (n = 22) and non-obese control participants (n = 20) at baseline and at a median of 6.5 months after surgery. Markers of systemic inflammation and glucose homeostasis were measured. Expression of pro-inflammatory genes and proto-oncogenes in the rectal mucosa was quantified using qPCR. Crypt cell proliferation state of the rectal mucosa was assessed by counting mitotic figures in whole micro-dissected crypts.ResultsAt 6.5 months post-surgery, participants had lost 29 kg body mass and showed improvements in markers of glucose homeostasis and in systemic inflammation. Expression of pro-inflammatory genes in the rectal mucosa did not increase and COX-1 expression fell significantly (P = 0.019). The mean number of mitoses per crypt decreased from 6.5 to 4.3 (P = 0.028) after RYGB.ConclusionRYGB in obese adults led to lower rectal crypt cell proliferation, reduced systemic and mucosal markers of inflammation and improvements in glucose regulation. These consistent findings of reduced markers of tumourigenic potential suggest that surgically induced weight loss may lower CRC risk.

The relationship between intestinal and oral mucosa microcirculation in anaesthetized horses

ObjectiveTo compare alteration in intestinal blood flow in anaesthetized horses with changes in oral mucosa blood flow. Study designProspective, randomized clinical study. AnimalsEight warmblood horses. MethodsAfter induction with guaifenesin and ketamine, anaesthesia was maintained with isoflurane at 1.5 vol% in oxygen. The tissue blood flow was measured using laser Doppler flowmetry at the jejunum, colon, rectal mucosa, oesophageal mucosa and the oral mucosa. After three baseline measurements, blood flow was first increased by dobutamine infusion and thereafter decreased by increasing isoflurane concentration and all measurements repeated twice. anova was used for comparing the measured parameters to baseline and correlation between the different measurement localizations was examined using Pearson correlation (p < 0.05). ResultsMicroperfusion at all measurement sites increased significantly during dobutamine infusion and decreased significantly during high isoflurane concentration. There was a significant correlation between flow at the oral mucosa and flow at the jejunum (r2 = 0.77, p = 0.002), colon (r2 = 0.76, p < 0.001), rectal mucosa (r2 = 0.88, p < 0.001) and oesophageal mucosa (r2 = 0.83, p <0.001). Conclusions and clinical relevanceOral mucosa blood flow can be used in isoflurane anaesthetized horses to reflect changes of intestinal microcirculation.

A Randomized Double-Blind Placebo-Controlled Trial of Fruit and Vegetable Concentrates on Intermediate Biomarkers in Head and Neck Cancer.

Background. Head and neck cancer (HNC) patients are at an increased risk for developing second primary tumors (SPTs). Diets rich in fruits and vegetables (FVs) may lower HNC risk. FV concentrates may offer a potential alternative to increasing FV intake. Methods. We conducted a randomized, double-blind, placebo-controlled trial to evaluate whether Juice PLUS+ (JP; a commercial product with multiple FV concentrates) has an effect on p27 and Ki-67, biomarkers associated with the risk of SPTs. During 2004-2008, we randomized 134 HNC patients to 12 weeks of JP (n = 72) or placebo (n = 62). Oral cavity mucosal biopsies and whole blood were obtained at baseline and after 12 weeks. All participants were given the opportunity to receive JP for 5 years following the end of the intervention period, and they were followed yearly for the development of SPTs. Results. After 12 weeks, patients on JP had significantly higher serum α-carotene (P = .009), β-carotene (P < .0001), and lutein (P = .003) but did not differ significantly in p27 (P = .23) or Ki-67 (P = .95). JP use following the initial 12-week trial was not significantly associated with SPT prevention. Conclusions. Despite increased serum micronutrient levels, our results do not suggest a clinical benefit of JP in HNC patients. Future studies should focus on longer intervention periods and/or modified supplement formulations with demonstrated chemopreventive properties.

Sublingual microvascular perfusion is altered during normobaric and hyperbaric hyperoxia

Hyperoxia and hyperbaric oxygen therapy can restore oxygen tensions in tissues distressed by ischemic injury and poor vascularization and is believed to also yield angiogenesis and regulate tissue perfusion. The aim of this study was to develop a model in which hyperoxia-driven microvascular changes could be quantified and to test the hypothesis that microcirculatory responses to both normobaric (NB) and hyperbaric (HB) hyperoxic maneuvers are reversible. Sublingual mucosa microcirculation vessel density, proportion of perfused vessels, vessel diameters, microvascular flow index, macrohemodynamic, and blood gas parameters were examined in male rabbits breathing sequential O2/air mixtures of 21%, 55%, 100%, and return to 21% during NB (1.0bar) and HB (2.5bar) conditions. The results indicate that NB hyperoxia (55% and 100%) produced significant decreases in microvascular density and vascular diameters (p<0.01 and p<0.05, respectively) accompanied by significant increases in systolic and mean arterial blood pressure (p<0.05, respectively) with no changes in blood flow indices when compared to NB normoxia. HB normoxia/hyperoxia resulted in significant decreases in microvascular density (p<0.05), a transient rise in systolic blood pressure at 55% (p<0.01), and no changes in blood vessel diameter and blood flow indices when compared to NB hyperoxia. All microcirculation parameters reverted back to normal values upon return to NB normoxia. We conclude that NB/HB hyperoxia-driven changes elicit reversible physiological control of sublingual mucosa blood perfusion in the presence of steady cardiovascular function and that the absence of microvascular vasoconstriction during HB conditions suggests a beneficial mechanism associated with maintaining peak tissue perfusion states.

Pilot Study of Laser Doppler Measurement of Flow Variability in the Microcirculation of the Palatal Mucosa

Background. Histopathological alterations can arise when the denture-supporting mucosa experiences microbial and mechanical stress through the denture base and diagnosis of these diseases usually follows microvascular changes. Microcirculation measurement could allow for detection of such dysfunction and aid in the early diagnosis of palatal mucosa pathologies. Materials and Methods. We tested the sensitivity of laser Doppler for measuring the microcirculation of the palatal mucosa, assessing the median raphe (MR), Schroeder area (SA), and retroincisive papilla (RP). A Doppler PeriFlux 5000 System, containing a laser diode, was used. 54 healthy participants were recruited. We compare the measurements of PU (perfusion unit) using ANOVA test. Results. The numerical values for palatal mucosa blood flow differed significantly among the anatomical areas (p = 0.0167). The mean value of Schroeder area was 92.6 (SD: 38.4) and was significantly higher than the retroincisive papilla (51.9) (SD: 20.2) (p < 0.05), which in turn was higher than that of median raphe (31.9) (SD: 24.2) (p < 0.0001). Conclusion. Schroeder area appeared to have the greatest sensitivity, and vascular flow variability among individuals was also greatest in this region. We suggest that analysis of blood stream modification with laser Doppler of the palatal mucosa can help to detect onset signs of pathological alterations.

Expression of miRNA-21 in colonic mucosa and peripheral blood CD4+ T cells of 49 patients with active inflammatory bowel disease

Objective To investigate the role and significance of miRNA-21 in the pathogenesis and development of inflammatory bowel disease (IBD). Methods The expressions of microRNA-21 (miRNA-21) in colonic mucosa and peripheral blood CD4+ T cells were analyzed by fluorescence quantitative polymerase chain reaction (PCR) in 26 patients with active Crohn's disease (CD), 23 patients with active ulcerative colitis (UC) and 19 healthy controls. The relative expression amount of miRNA-21 in colonic mucosal and peripheral blood CD4+ T cells in 11 patients with CD was compared before and after infliximab (IFX) treatment, and its correlation with tumor necrosis factor(TNF)-α was analyzed. t-test was performed for comparison between groups. The correlation between miRNA-21 expression in peripheral blood CD4+ T cells and serum TNF-α was analyzed by Spearman correlation analysis. Results The expression of miRNA-21 in colonic mucosa of CD patients and UC patients was 4.720±0.397 and 4.993±0.415, respectively, which were both higher than that of healthy control group (1.101±0.284), and the differences were statistically significant (t=7.657 and 8.356, both P<0.01). The expression of miRNA-21 in peripheral blood CD4+ T cells of CD patients and UC patients was 3.254±0.323 and 3.450±0.311, which were both higher than that of healthy control group (0.891±0.220), and the differences were statistically significant (t=6.007 and 7.098, both P<0.01). After 12 weeks of IFX treatment, simple endoscopic score for Crohn's disease (SES-CD) of CD patients was 8.019±0.349, which was lower than that before treatment (21.502±1.185), and the difference was statistically significant (t=10.910, P<0.01). The serum TNF-α level was 61.570±6.252, which was lower than that before treatment (173.500±12.670), and the difference was statistically significant (t=7.926, P<0.01). The results of correlation analysis indicated that serum TNF-α level was positively correlated with miRNA-21 expression in peripheral blood CD4+ T cells (r=0.780 4, P<0.01). Conclusions The increasing of miRNA-21 expression in IBD was closely correlated with the serum TNF-α level and severity of inflammation. miRNA-21 might be a new target for IBD treatment. Key words: miRNA-21; Inflammatory bowel diseases; Crohn disease; Colitis, ulcerative

An Evaluation of Invasive Fungal Sinusitis Outcomes Following Frozen Section Guided Surgical Debridement

Invasive fungal rhinosinusitis is an aggressive mycosis of the nasal cavity with frequent extension to adjacent facial and cranial structures. Pathologically, invasive fungal rhinosinusitis is defined as infiltration of fungal organisms within mucosal tissue, blood vessels, or intracranial structures. These infections typically occur in immunocompromised individuals, such as hematologic malignancy patients, uncontrolled diabetics, or transplant patients. Prognosis is typically …

Research progress of narrow band imaging in the diagnosis of early esophageal cancer

Early diagnosis of esophageal cancer is essential for improving both the effectiveness of esophageal cancer treatment and the prognosis of patients. As a new technology for esophageal cancer early diagnosis, narrow-band imaging (NBI) enables surgeon to clearly observe the mucosa and submucosal blood vessels changes in early esophageal cancer. It has initially shown excellent application value in the early diagnosis.In particular it has obvious advantages to the ordinary white light endoscopy which is currently used in esophageal cancer early diagnosis. If combined with Lugol iodine staining , magnifying endoscopy and other diagnostic methods in clinical, NBI will have a better value in early diagnosis of esophageal. Key words: Esophageal neoplasms; Early diagnosis; Endoscopy; Narrow band imaging

Psychological and physiological aspects of stress in atopic patients

mucosal humoral immunity has been identified in the small intestine, however little is known about the type of antibody response. We characterized the mucosal immunoglobulins (Ig) isotype and its association with IBS pathophysiology. Methods: Mucosal jejunal biopsies, stool and blood samples wereobtained fromhealthyvolunteers (H;n=18)andage-matched participantsmeeting diarrhoea-IBS Rome III criteria (IBS-D; n=20). Bowel movements, stool consistency and abdominal pain were monitored (10 days prior to biopsy). Psychological stress and depressionwere assessedwith validated questionnaires. The number and ultrastructure of mucosal plasma cells were determined by transmission electron microscopy, and mucosal IgG+ cells were quantifiedby immunofluorescence. Igswere quantified in stool and blood by ELISA technique. Results: The number of mucosal IgG+ cells and plasma cells was increased in IBS-D patients, the later in close proximity to nerve fibres, respect to H (P<0.05). Plasma cells displayed signs of activation but the presence of cell clusters was more abundant in the IBS-D group. IgG in faeces was higher in IBS-D than in H (P<0.05). Plasma cells-nerves proximity correlated with stress and depression, and IgG in faeces correlated with abdominal pain (P<0.05). Conclusion: IgG production rises as a distinctive marker of mucosal immuneactivity in associationwith clinical characteristics in IBS-D. Studies aimed at determining IgG subtype and antigens eliciting such responses warrant further investigation.

A fiberoptic sensor for tissue carbon dioxide monitoring.

We present a new fiberoptic carbon dioxide sensor for transcutaneous and mucosa (indwelling) blood gas monitoring. The sensor is based on optical fluorescence of molecules sensitive to pH changes associated with dissolved CO2. A three layer chemical coating was dip-coated onto the distal tip of an optical fiber (600μm core radius). It contained the 50mg/ml `polym H7', a coating polymer bonded to a fluorescence indicator dye, along with 125mg/ml of the transfer agent tetraoctylammonium hydroxide (TONOH). Light from a blue (460 nm) LED was launched into the fiber to excite the sensing film. The sensing film fluoresced green (530 nm), the intensity of which decreased in the presence of CO2. The sensor was tested in vitro, finding a correlation between change in fluorescence (in AU) and aqueous CO2 concentration with a minimum detection threshold of 40%. The sensor is being developed for medical applications where its small size and ability to continuously monitor the partial pressure of CO2 (PCO2) will make it an extremely useful diagnostic tool.

Rapid multispectral endoscopic imaging system for near real-time mapping of the mucosa blood supply in the lung.

We have developed a fast multispectral endoscopic imaging system that is capable of acquiring images in 18 optimized spectral bands spanning 400-760 nm by combining a customized light source with six triple-band filters and a standard color CCD camera. A method is developed to calibrate the spectral response of the CCD camera. Imaging speed of 15 spectral image cubes/second is achieved. A spectral analysis algorithm based on a linear matrix inversion approach is developed and implemented in a graphics processing unit (GPU) to map the mucosa blood supply in the lung in vivo. Clinical measurements on human lung patients are demonstrated.

Electroacupuncture at Zusanli Prevents Severe Scalds-Induced Gut Ischemia and Paralysis by Activating the Cholinergic Pathway.

Severe burn injuries may result in gastrointestinal paralysis, and barrier dysfunction due to gut ischemia and lowered vagus excitability. In this study we investigate whether electroacupuncture (EA) at Zusanli (ST36) could prevent severe scalds-induced gut ischemia, paralysis, and barrier dysfunction and whether the protective role of EA at ST36 is related to the vagus nerve. 35% burn area rats were divided into six groups: (a) EAN: EA nonchannel acupoints followed by scald injury; (b) EA: EA at ST36 after scald injury; (c) VGX/EA: vagotomy (VGX) before EA at ST36 and scald injury; (d) VGX/EAN: VGX before EAN and scald injury; (e) atropine/EA: applying atropine before scald injury and then EA at ST36; (f) atropine/EAN: applying atropine before scald injury and then EA at nonchannel acupoints. EA at the Zusanli point significantly promoted the intestinal impelling ratio and increased the amount of mucosal blood flow after scald injury. The plasma diamine oxidase (DAO) and intestinal permeability decreased significantly after scald injury in the EA group compared with others. However, EA after atropine injection or cervical vagotomy failed to improve intestinal motility and mucosa blood flow suggesting that the mechanism of EA may be related to the activation of the cholinergic nerve pathway.

Comparing Contact Pressure Induced by a Conventional Complete Denture and an Implant-Retained Overdenture

Implant-retained overdenture has been widely applied as a solution to edentulous ageing; however, a major concern for the denture wearers is bone resorption induced by the prosthetic interaction with soft tissue and bone. Early studies have revealed that the bone resorption is associated with the disturbance to the mucosa blood flow. This study aimed to investigate the contact pressure induced by an implant-retained overdenture, compared to a conventional complete denture without implants, which implies the potential bone resorption for clinical investigation. A three-dimensional finite element model of a full jaw, including mandible bone, mucosa, and denture, was created through a reverse engineering method based on CBCT images, in which the hyperelastic behaviour of mucosa was determined by curve-fitting to the clinical measurement, for a more realistic response. It is found that the location of the bone loss differed between the implant retained and non-implant complete dentures. With the implants, the denture displaced more at posterior ends towards the mucosa bearing area, leading to higher contact pressure accounted for more severe local bone loss.

Multiple gastrointestinal stromal tumors with novel germline c-kit gene mutation, K642T, at exon 13

Multiple gastrointestinal stromal tumors (GISTs) caused by germline c-kit gene mutations are an extremely rare autosomal dominant disorder. A 57-year-old Japanese woman was referred to a hospital for appetite loss and severe weight loss. She had 2 large abdominal masses around the stomach, which were surgically resected. Histological examination revealed that these tumors were GISTs. Multiple microscopic GISTs and diffuse hyperplasia of the interstitial cells of Cajal were also seen in the background gastric and small intestinal walls. Characteristically, the GISTs showed severe hyalinization with calcification and partial heterotopic ossification, which may have caused the patient's severe dysphagia. Mutational analysis of the c-kit gene revealed a substitution at codon 642 in exon 13 (K642T) in the tumor, normal ileal mucosa and peripheral blood leukocytes, indicating that the mutation is in the germline. This is the first case of multiple GISTs with novel germline c-kit gene mutation at exon 13.

Premedication with clonidine before TIVA optimizes surgical field visualization and shortens duration of endoscopic sinus surgery - results of a clinical trial

During functional endoscopic sinus surgery (FESS), intraoperative bleeding can significantly compromise visualization of the surgical field. Clonidine constricts peripheral blood vessels and reduces systemic blood pressure, which in combination decrease nasal mucosa blood flow. This dual effect can potentially reduce bleeding during FESS and stabilize the intraoperative hemodynamic profile of the patient. The aim of this prospective study was to assess if the quality of the surgical field visualization during FESS was improved when clonidine was used as a premedication agent. A group of 44 patients undergoing FESS for chronic sinusitis and polyp removal were enrolled and randomly assigned to receive either oral clonidine or midazolam as preoperative premedication. During the operation, the quality of the surgical field was assessed and graded by the operating surgeon using the scale proposed by Boezaart. The evaluations were done during surgery at 15 minutes (K1), 30 minutes (K2), 60 minutes (K3) and 120 minutes (K4) after incision. The duration of the surgical procedure was significantly shorter in the clonidine group: mean time of surgery: 80 vs. 96 min in the clonidine and midazolam groups, respectively. Also better quality of surgical field was observed at all time points in the clonidine group. Premedication with clonidine before FESS results in shortening of the surgical time and a better quality of the surgical field.

Estrés oxidativo en la enfermedad de Crohn

Crohn's disease (CD) is characterized by transmural inflammation that is most frequently located in the region of the terminal ileum. Although the physiopathological mechanisms of the disease are not yet well defined, the unregulated immune response is associated with high production of reactive oxygen species (ROS). These elements are associated with complex systems known as antioxidant defenses, whose function is ROS regulation, thereby preventing the harmful effects of these elements. However, the presence of an imbalance between ROS production and ROS elimination by antioxidants has been widely described and leads to oxidative stress. In this article, we describe the most significant findings on oxidative stress in the intestinal mucosa and peripheral blood.

Sa1289 Non Celiac Gluten Sensitivity: Lack of Response to In Vitro Gliadin Challenge and Basophils Activation Assay

In recent years it has become more frequent for physicians to come across types of gluten sensitivity other than celiac disease (CD). Regardless of the absence of any serological CD markers or intestinal damage, gluten sensitive (GS) patients often report intestinal and extraintestinal symptoms shortly after the ingestion of gluten and the disappearance of such symptoms on a gluten free diet (GFD). Regrettably, at present, there is no evidence of any mucosal or serological modifications in GS patients, or that gluten is really the trigger factor in gluten sensitivity. We aimed at evaluating the impact of gliadin challenge on two experimental settings, i.e. in vitro gliadin challenge of duodenal mucosa and peripheral blood basophils in GS patients compared to CD patients and healthy controls. We consecutively enrolled patients referred to tertiary centers for food intolerance and celiac disease. Participants underwent a complete clinical screening in order to rule out CD (serum a-tTG, EMA, total IgA and HLA status, where appropriate), an interview for evaluation of diet and symptoms, a skin prick test to exclude wheat allergy, upper endoscopy for duodenal biopsies used for both histological assessment and for the in vitro evaluation of the gliadin-induced mucosal expression of early and late inflammatory markers: PY99, epithelial HLA-DR, ICAM1, crypt HLA-DR, CD3, CD25 and CD69. In addition, a basophils activation assay, in which patients' basophils were challenged with a gliadin extract, was performed. Basophils were analyzed for the expression of hematopoietic membrane antigens CD203c, CD63 and CD45 by flow cytometry looking at differences in antigen expression. 119 subjects were screened for CD and GS and, according to the results, four groups were obtained: GS patients (no.16), CD on gluten free diet (no.34), CD on gluten containing diet (no.35) and healthy controls (no.34). As for the in vitro gliadin challenge, all CD patients, regardless of their dietetic status, showed a clear mucosal activation (increased immunofluorescence intensity both for early and delayed inflammation markers) when stimulated with gliadin, while only 3 controls and 3 GS patients showed an weak response for some, not all, inflammation markers. Also, there were no significant differences in the skin prick test results or in the level of CD63 and CD203c basophils expression, used as a marker of cell activation, among the groups. The present study shows that in GS patients, gliadin challenge test did not show any significant modifications in the expression of those mucosal inflammation markers found increased in CD patients. Therefore, this tool should not be used as a diagnostic instrument in case of GS. Moreover, the lack of differences in basophils activation and skin prick test seems to exclude this form of cellular sensitivity in our GS series also.

MyD88 adaptor-like (Mal) functions in the epithelial barrier and contributes to intestinal integrity via protein kinase C.

MyD88 adapter-like (Mal)-deficient mice displayed increased susceptibility to oral but not intraperitoneal infection with Salmonella Typhimurium. Bone marrow chimeras demonstrated that mice with Mal-deficient non-hematopoietic cells were more susceptible to infection, indicating a role for Mal in non-myeloid cells. We observed perturbed barrier function in Mal(-/-) mice, as indicated by reduced electrical resistance and increased mucosa blood permeability following infection. Altered expression of occludin, Zonula occludens-1, and claudin-3 in intestinal epithelia from Mal(-/-) mice suggest that Mal regulates tight junction formation, which may in part contribute to intestinal integrity. Mal interacted with several protein kinase C (PKC) isoforms in a Caco-2 model of intestinal epithelia and inhibition of Mal or PKC increased permeability and bacterial invasion via a paracellular route, while a pan-PKC inhibitor increased susceptibility to oral infection in mice. Mal signaling is therefore beneficial to the integrity of the intestinal barrier during infection.

Monitoring microcirculatory blood flow with a new sublingual tonometer in a porcine model of haemorrhagic shock

Tissue capnometry may be suitable for the indirect evaluation of regional hypoperfusion. We tested the performance of a new sublingual capillary tonometer in experimental hemorrhage. Thirty-six anesthetized, ventilated mini pigs were divided into sham-operated (n = 9) and shock groups (n = 27). Hemorrhagic shock was induced by reducing mean arterial pressure (MAP) to 40 mmHg for 60 min, after which fluid resuscitation started aiming to increase MAP to 75% of the baseline value (60-180 min). Sublingual carbon-dioxide partial pressure was measured by tonometry, using a specially coiled silicone rubber tube. Mucosal red blood cell velocity (RBCV) and capillary perfusion rate (CPR) were assessed by orthogonal polarization spectral (OPS) imaging. In the 60 min shock phase a significant drop in cardiac index was accompanied by reduction in sublingual RBCV and CPR and significant increase in the sublingual mucosal-to-arterial PCO2 gap (PSLCO2 gap), which significantly improved during the 120 min resuscitation phase. There was significant correlation between PSLCO2 gap and sublingual RBCV (r = -0.65, p < 0.0001), CPR (r = -0.64, p < 0.0001), central venous oxygen saturation (r = -0.50, p < 0.0001), and central venous-to-arterial PCO2 difference (r = 0.62, p < 0.0001). This new sublingual tonometer may be an appropriate tool for the indirect evaluation of circulatory changes in shock.

Using dynamic analysis of Laser-Doppler blood flowmetry to measure nasal mucosa bloody flow in postural changes

The regulation of nasal mucosa blood flow (NMBF) is affected by multiple factors, such as the autonomic nervous system, medications, temperature, humidity, endocrine, even emotional stress and vision. The effects of postural changes on NMBF have been described in numerous studies. However, the results are far from consistent due to different experimental designs. Dynamic analysis of Laser-Doppler blood flowmetry (LDBF) is employed to recognize the effect of postural changes on NMBF. NMBF was continuously measured by LDBF in 14 participants with changing postures (sitting and supine). NMBF was measured in Blood Perfusion Unit (BPU), equivalent to the number of red blood cells multiplied by their mean velocity in a measured volume. NMBF increases significantly in a supine posture compared with that in a sitting posture. Our study demonstrates that NMBF is significantly influenced after initial postural change, suggesting that changes in posture may be regarded as an important factor regulating NMBF.