Evaluation of gingival microcirculation in patients with gestational diabetes mellitus.

OBJECTIVE: The aim of this study was to evaluate the possible microcircularity variations at periodontal mucous level in patients with gestational diabetes mellitus (GDM). MATERIAL AND METHODS: Overall 55 periodontally healthy and non-smoker participants were enrolled in the study by whom 30 were diagnosed with GDM (26 to 34 weeks pregnant) and 25 were systemically healthy unpregnant controls. The analysis was performed in the masticatory/gingival mucosa of maxillary anterior region and by the optical probe videocapillaroscopy technique equipped with 200× lenses. The following parameters were recorded: capillary loop visibility, capillary orientation to surface, microhemorrhages, capillary density and tortuosity. RESULTS: The average capillary density was significantly higher in participants with GDM (27 ± 5.46 no. loops/mm2) compared to controls (21.16 ± 3 no. loops/mm2) (P = 0.035) while increased tortuosity scores was observed in controls compared with the GDM group (P = 0.017). There was not any significantly difference between study groups among the other variables (P > 0.05). CONCLUSIONS: Capillary alterations including capillary density and tortuosity were demonstrated in gingival microcirculation of patients with GDM. These microcirculatory changes could provide us new understanding on the dynamics of the relationship between GDM and periodontal tissues.

Visualising brain capillaries in magnetic resonance images via supramolecular self-assembly.

We report the supramolecular self-assembly of one fluorescein and three Gd-chelate conjugated 8-arm polyethylene glycols (8-arm PEG-FGd3) for visualising the capillaries of the brain in magnetic resonance imaging (MRI).

Distribution analysis of infantile hemangioma or capillary malformation on the head and face in Japanese patients.

Infantile hemangioma is one of the most common tumors in infancy. Delivery may be a clue for the trigger of infantile hemangioma formation in the head and face areas. In this study, we tried to plot localization of infantile hemangioma as well as capillary malformation on the head and face, and compared them to identify their characteristics and risk factors. The distribution of 104 lesions in 100 patients with infantile hemangioma was as follows: 32 lesions on the head, 12 on the forehead, 57 on the cheek and three in the jaw area. We could not find a statistically significant correlation of the distribution with three clinical subtypes (superficial, deep and mixed), sex or size of the lesions. However, the lesions in the jaw or chin areas were significantly less frequent than other areas (P = 0.0008 or 0.03, respectively). This tendency was not found in 40 patients with capillary malformation. Mechanical stress to jaw or chin areas may be less than other areas in normal cephalic delivery. Considering the emergence after birth and age-dependent involution of infantile hemangioma, we speculate that physiological events including perinatal hypoxia or mechanical stress during delivery as the trigger of hemangioma formation. Taken together, our results may reveal the contribution of mechanical stress to the trigger of infantile hemangioma, not capillary malformation, and may facilitate clinical differentiation between the two diseases by their localization. Further studies with an increased number of patients will be necessary to validate the finding.

Visualization of the intrarenal distribution of capillary blood flow.

This study describes a modified technique to fill the renal vasculature with a silicon rubber (Microfil) compound and obtain morphologic information about the intrarenal distribution of capillary blood flow under a variety of conditions. Kidneys and cremaster muscles of rats were perfused in vivo with Microfil using a perfusion pressure equal to the animal's mean arterial pressure at body temperature. Microfil did not alter arteriolar diameter or the pattern of flow in the microcirculation of the cremaster muscle. The modified protocol reproducibly filled the renal vasculature, including; glomerular, peritubular, and vasa recta capillaries. We compared the filling of the renal circulation in control rats with that seen in animals subjected to maneuvers reported to alter the intrarenal distribution of blood flow. Infusion of angiotensin II, hypotension, volume expansion, and mannitol- or furosemide-induced diuresis redistributed flow between renal cortical and medullary capillaries. The advantage of the current technique is that it provides anatomical information regarding the number, diameter, and branching patterns of capillaries in the postglomerular circulation critical in determining the intrarenal distribution of cortical and medullary blood flow.

3D-Imaging of Whole Neuronal and Vascular Networks of the Human Dental Pulp via CLARITY and Light Sheet Microscopy.

Direct visualization of the spatial relationships of the dental pulp tissue at the whole-organ has remained challenging. CLARITY (Clear Lipid-exchanged Acrylamide Tissue hYdrogel) is a tissue clearing method that has enabled successful 3-dimensional (3D) imaging of intact tissues with high-resolution and preserved anatomic structures. We used CLARITY to study the whole human dental pulp with emphasis on the neurovascular components. Dental pulps from sound teeth were CLARITY-cleared, immunostained for PGP9.5 and CD31, as markers for peripheral neurons and blood vessels, respectively, and imaged with light sheet microscopy. Visualization of the whole dental pulp innervation and vasculature was achieved. Innervation comprised 40% of the dental pulp volume and the vasculature another 40%. Marked innervation morphological differences between uni- and multiradicular teeth were found, also distinct neurovascular interplays. Quantification of the neural and vascular structures distribution, diameter and area showed that blood vessels in the capillary size range was twice as high as that of nerve fibers. In conclusion whole CLARITY-cleared dental pulp samples revealed 3D-morphological neurovascular interactions that could not be visualized with standard microscopy. This represents an outstanding tool to study the molecular and structural intricacies of whole dental tissues in the context of disease and treatment methods.

Transmitted ultrasound pressure variation in micro blood vessel phantoms.

Silica, cellulose and polymethylmethacrylate tubes with inner diameters of ten to a few hundred microns are commonly used as blood vessel phantoms in in vitro studies of microbubble or nanodroplet behavior during insonation. However, a detailed investigation of the ultrasonic fields within these micro-tubes has not yet been performed. This work provides a theoretical analysis of the ultrasonic fields within micro-tubes. Numerical results show that for the same tube material, the interaction between the micro-tube and megaHertz-frequency ultrasound may vary drastically with incident frequency, tube diameter and wall thickness. For 10 MHz ultrasonic insonation of a polymethylmethacrylate (PMMA) tube with an inner diameter of 195 microm and an outer diameter of 260 microm, the peak pressure within the tube can be up to 300% of incident pressure amplitude. However, using 1 MHz ultrasound and a silica tube with an inner diameter of 12 microm and an outer diameter of 50 microm, the peak pressure within the tube is only 12% of the incident pressure amplitude and correspondingly, the spatial-average-time-average intensity within the tube is only 1% of the incident intensity.

Rapid palatal expansion: the role of microcirculation.

AIM: Transverse palate modifications fall under expansive orthopedic therapy of the upper maxilla. The only practical approach to the problem on the transverse plane is that of performing the expansion of the maxillary arch through an opening of the median palatal suture. It is important to understand the changes of the vascular network in midpalatal suture following the starting of rapid maxillary expansion. It is critical to maintain the blood supply and circulation for the osteogenesis and bone remodeling after the expansion. The aim of this research was to evaluate the effects of rapid orthopedic expansion (REP) at the microcirculatory level through capillaroscopic examination. METHODS: Fifteen patients in their developing years between 9 and 15 years of age (average age 12.16 years) were examined. The application of the REP was the first step in the planning of orthopedic-orthodontic treatment which foresaw further stages in the odonto-osseous movement. The method of Biomicroscopic Video-Imaging of the microcirculation of oral mucosa is performed through the technique of computerized capillaroscopy and the related software. RESULTS: From the results it is evident that immediately after achieving the expansion of the upper maxilla (t1), a slight decrease in the number of vessels per mm² can be observed. In addition, a slight ectasia can be observed in these vessels in comparison to t0. Comparing the videocapillaroscopic images of t1 and t2, an increase in the capillaries per mm² can be observed. CONCLUSION: Ectasia of the capillaries, though subject to strictly individual variables, can be considered perfectly normal and it is compatible with the normal biology and physiology of vessel microcirculation.

In vitro contrast-enhanced ultrasound measurements of capillary microcirculation: comparison between polymer- and phospholipid-shelled microbubbles.

The focus of contrast-enhanced ultrasound research has developed beyond visualizing the blood pool and its flow to new areas such as perfusion imaging, drug and gene therapy, and targeted imaging. In this work comparison between the application of polymer- and phospholipid-shelled ultrasound contrast agents (UCAs) for characterization of the capillary microcirculation is reported. All experiments are carried out using a microtube as a vessel phantom. The first set of experiments evaluates the optimal concentration level where backscattered signal from microbubbles depends on concentration linearly. For the polymer-shelled UCAs the optimal concentration level is reached at a value of about 2×10(4)MB/ml, whereas for the phospholipid-shelled UCAs the optimal level is found at about 1×10(5)MB/ml. Despite the fact that the polymer shell occupies 30% of the radius of microbubble, compared to 0.2% of the phospholipid-shelled bubble, approximately 5-fold lower concentration of the polymer UCA is needed for investigation compared to phospholipid-shelled analogues. In the second set of experiments, destruction/replenishment method with varied time intervals ranging from 2ms to 3s between destructive and monitoring pulses is employed. The dependence of the peak-to-peak amplitude of backscattered wave versus pulse interval is fitted with an exponential function of the time γ=A(1-exp(-ßt)) where A represents capillary volume and the time constant ß represents velocity of the flow. Taking into account that backscattered signal is linearly proportional to the microbubble concentration, for both types of the UCAs it is observed that capillary volume is linearly proportional to the concentration of the microbubbles, but the estimation of the flow velocity is not affected by the change of the concentration. Using the single capillary model, for the phospholipid-shelled UCA a delay of about 0.2-0.3s in evaluation of the perfusion characteristics is found while polymer-shelled UCA provide response immediately. The latter at the concentration lower than 3.6×10(5)MB/ml have no statistically significant delay (p<0.01), do not cause any attenuation of the backscattered signal or saturation of the receiving part of the system. In conclusion, these results suggest that the novel polymer-shelled microbubbles have a potential to be used for perfusion evaluation.

A study of microangioneogenesis in wounds healing by secondary intention.

A method is described for the study of microangioneogenesis in wounds healing by secondary intention. Standard skin defects were created on the backs of Sprague-Dawley rats and angiograms of the new vessels in the healing wounds were performed at subsequent time intervals. The technique allowed comparison of the rate of new vessel formation in wounds covered with a hydrogel surgical dressing with those healing without a dressing. It was found that the rate of new capillary formation was faster in the covered wounds.

Revascularization of the rabbit temporomandibular joint after surgical intervention: a histologic and microangiographic study.

Postsurgical revascularization of the rabbit temporomandibular joint (TMJ) after discoplasty was studied at the gross and microscopic levels. Surgical disruption of the lateral and medial articular blood vessels resulted in revascularization of the joint by the transverse facial artery. Deep branches of the transverse facial artery provided vascular supply to the anterior TMJ until the lateral and medial articular vessels could be re-established. The greatest change in vascularity was observed between the second and third postoperative weeks. It was concluded that discoplasty in the rabbit TMJ is a biologically sound surgical procedure, with the majority of vascularity re-established by three weeks and complete healing at six weeks.

Capillary hemangioma of the maxilla. A report of two cases in which angiography and embolization were used.

This article presents two clinical cases of capillary hemangiomas of the maxilla. Such lesions are rare, as demonstrated by the review of the literature included in this article. The presentation, differential diagnosis, histopathology, management, and follow-up for each case are discussed. Our rationale for approaching these types of lesions, as well as our opinion that microembolization should be considered as a first line approach to treatment, is presented.