Comparação entre subtração radiográfica digital e radiografia digital direta na detecção de reabsorções radiculares / Comparison between radiographic digital subtraction and direct digital radiography in the detection of root resorption

A reabsorção severa da raiz diagnosticada tardiamente pode acarretar a perda dentária. Devido ao fato de a técnica de subtração radiográfica digital ser um importante recurso para detecção precoce de alterações minerais, este estudo propôs avaliar a eficiência no diagnóstico precoce da reabsorção radicular externa simulada nas regiões apical e lingual, pelas técnicas de subtração radiográfica digital e radiografia digital. Foram utilizados 14 dentes incisivos de mandíbulas humanas maceradas com reabsorções de diferentes dimensões, simuladas nas regiões apical e lingual, e radiografados com variação de ângulos de projeção. As radiografias foram subtraídas pelo programa Regeemy®, e para avaliação de desempenho dos métodos de diagnóstico, pares de radiografias periapicais e imagens subtraídas foram apresentadas a dois radiologistas. De acordo com os resultados, não foram observadas diferenças estatisticamente significantes entre os métodos na detecção de reabsorções linguais, independentemente do tamanho da lesão. Também não houve diversidade entre os métodos na detecção de reabsorções apicais, com exceção do examinador dois quanto às variações angular vertical e horizontal de 10º, utilizando o maior nível de desgaste, que apresentou a radiografia digital como método superior na avaliação em relação à subtração radiográfica. Também foi observado que o aumento do nível de desgaste permitiu melhor avaliação nas regiões de reabsorções apicais e linguais, e a menor variação dos ângulos verticais e horizontais nas detecções de reabsorções apicais e linguais permitiu uma melhor avaliação da imagem, principalmente no menor nível de desgaste.

The delay on diagnose severe root resorption can lead to tooth loss. Due to the fact that digital subtraction radiography is an important resource to detect initial mineral changes, this study aimed at evaluating the effectiveness of the digital subtraction radiography and digital radiography in early diagnosis of the simulated apical and lingual external root resorption. Fourteen human lower incisors, submitted to simulated apical and lingual resorption cavities of different sizes, imaged with different angle projection variations were included in this study. The images were subtracted by the Regeemy® program, and receiver operating characteristic analysis was used to evaluate the diagnostic performance for each imaging system, and the diagnostic accuracy of both diagnosis methods for detecting lesions was conducted by the assessment of the pairs of radiography (digital and subtracted) by two radiologists. According to the results, there were no statistically significant differences between the methods in detecting lingual resorption, independently of the lesion dimension. There was also no difference on the apical resorption detection, except by the viewer two as to 10º horizontal and vertical angles, who related that on the larger cavity, the digital radiography was more reliable than the subtraction radiography. It was also further noticed that the deeper the cavity size, the better the apical and lingual resorption detection; and the radiography taken of the apical and lingual resorption, with the smaller vertical and horizontal angles variation ensured a better assessment of the image, mainly on the shallower cavity size.

[Primary right ventricular malignant fibrous histiocytoma; report of a case].

Primary malignant fibrous histiocytoma located in the right side of the heart is extremely rare. We reported a case with literal reviews. A 71-year-old woman was admitted of faintness due to hypotension and marked edema of her lower extremity. With no time she was deteriorated into cardiogenic shock. Echocardiography demonstrated a tumor like mass which occupied her whole right ventricular cavity. Emergency tumor resection was carried out because of her status. Histological and immunohistochemical studies revealed the tumor was malignant fibrous histiocytoma. She died of pulmonary failure on nineteenth day after surgery.

Pulmonary metastasis from endometrial carcinoma.

The objective of this article is to investigate the clinical features of pulmonary metastasis (PM) from endometrial adenocarcinoma, in particular, the predictors of prolonged survival after PM detection. Fifteen patients who developed PM and underwent chest computed tomography (CT) scans for evaluation of PM were studied: 12 patients with pulmonary recurrence and 3 patients with PM on presentation. All patients with bilateral nodules or lymphangitic spread had metastases in other sites prior to or concomitant with PM, most of which were detected in para-aortic lymph nodes and/or the vaginal wall, while only one of five patients with a limited number (n < or = 5) of unilateral nodules had these metastases. The median survival time for the 10 patients with bilateral PMs was significantly shorter than that of the 5 patients with a limited number of unilateral nodules who were treated with surgery (7 versus 50 months, P = 0.005). Patients who developed pulmonary recurrence 2 years after the initial therapy had a significantly longer survival than those who developed it within 2 years (31 versus 10 months, P = 0.01). In conclusion, the distribution of PM determined by CT scans and the time interval between the initial therapy and the detection of pulmonary recurrence are the predictors of survival after PM detection.

Theoretical proof of edge search strategy applied to power plant start-up scheduling.

Power plant start-up scheduling is aimed at minimizing the start-up time while limiting maximum turbine rotor stresses. This scheduling problem is highly nonlinear and has a number of local optima. In our previous research, we proposed an efficient search model: genetic algorithms (GAs) with enforcement operation to focus the search along the edge of the feasible space where the optimal schedule is supposed to stay. Based on a nonlinear dynamic simulation and a linear inverse calculation with the iteration method, the enforcement operation is applied to move schedules generated by GA toward the edge. We prove that the optimal schedule lies on the edge, ensuring that searching along the edge instead of the entire space can improve the search efficiency significantly without missing the optimum. Furthermore, we provide a theoretical setting equation for the inverse enforcement gains of the linear inverse calculation, intended to move schedules closer to the edge at each iteration of the enforcement operation. The theoretical setting equation is verified and discussed with the test results. We propose the theoretical setting equation with the test results as a guideline for the use of our proposed search model: GA with enforcement operation.

Effects of collagen matrix containing transforming growth factor (TGF)-beta(1) on wound contraction.

We evaluated the effectiveness of transforming growth factor (TGF)-beta(1) on wound contraction, both alone and in combination with collagen matrix, using an in vivo delayed wound healing type model. To clarify the mechanisms involved in the effectiveness of TGF-beta(1), we also used a fibroblast-populated collagen gel contraction in vitro model. Although we found that TGF-beta(1) significantly accelerated contraction of the fibroblast-populated collagen gel in vitro, we demonstrated that both collagen matrix alone and 1.0 microg of TGF-beta(1) alone significantly inhibited wound contraction in the in vivo model. In addition, the combination of TGF-beta(1) and collagen matrix was much more effective than TGF-beta(1) alone, a finding which was supported by histopathological examination. Wounds treated with collagen matrix containing TGF-beta(1) showed horizontal rearrangement of collagen fibers in the dermal part as well as evidence of active fibroblast proliferation, which was not observed in the scar regions of controls. These results show that the application of TGF-beta(1) treated collagen matrix is effective for preventing contraction producing so called "neodermis" in treating a delayed healing type model and may be highly beneficial for treating chronic wounds.

Sertoli-stromal cell tumor of the ovary: immunohistochemical, ultrastructural, and genetic studies.

The Sertoli-stromal cell tumor (SSCT) of the ovary shows a histologic resemblance to developing or adult testes and is often associated with virilization caused by tumor-produced androgenic hormone. In spite of the unique manifestation of SSCT, detailed characteristics of this tumor are still obscure. The mechanism by which SSCT occurs has not yet been determined. Six SSCTs were studied immunohistochemically, ultrastructurally, and by polymerase chain reaction (PCR) for the presence of sex-determining region Y (SRY) gene and the X chromosome activation state. Immunohistochemically, Sertoli-like cells of SSCT were positive not only for alpha-inhibin but also low-molecular-weight cytokeratin. In control testes, the expression of alpha-inhibin and cytokeratin was limited to a Sertoli cell component and rete testis, respectively. Ultrastructurally, tumor cells composing hollow tubules had an elongated nucleus with deep indentation and annulate lamellae, which are characteristic structures of mature Sertoli cells. In addition, they had studded microvilli on the apical surface and frequent desmosomes, which are structures noted in the cells of rete testis. Histologically, tumor cells of hollow tubules sometimes pouted into the lumen, as did the cells of tubulae rete, entrance into rete testis from seminiferous tubules. All of these findings indicate that some tumor cells of a SSCT show simultaneous differentiation into both Sertoli cells and cells of rete testis. SRY gene was not detected in any cases, and the X chromosome activation pattern was the same as that of the female control.

Endometrioid adenocarcinoma arising from adenomyosis: report and immunohistochemical analysis of an unusual case.

A case of endometrioid adenocarcinoma arising from adenomyosis is reported. The patient was a 53-year-old woman who complained of vulvar itching. Smear cytology of the endometrium revealed adenocarcinoma. Magnetic resonance imaging of the pelvis revealed a lesion with a slightly high intensity in the uterine fundus on a T2-weighted image. Semiradical total hysterectomy and bilateral adnexectomy were performed, followed by chemotherapy. Histologically, the lesion in the uterine fundus was composed mostly of adenocarcinoma with stromal invasion. There were many adenomyotic foci in and around the carcinoma, including some showing transition to adenocarcinoma. There was no malignant finding in the normally situated endometrium. The carcinoma invaded in the myometrium, involving the uterine serosa, but no dissemination to the peritoneal cavity was found. The carcinoma was, therefore, considered to be endometrioid adenocarcinoma arising from adenomyosis. Immunohistochemistry showed expression of p53 oncoprotein and Ki-67 antigen in the carcinoma cells. The value of immunohistochemistry in predicting prognosis is discussed.

Technique for fixing a temporalis muscle using a titanium plate to the implanted hydroxyapatite ceramics for bone defects.

We devised a technique to fix the temporalis muscle to the transplanted hydroxyapatite implant by using a titanium plate, which is fixed to the hydroxyapatite ceramic implant by screws and achieves good clinical results. The size, shape, and curvature of the hydroxyapatite ceramic implants were determined according to full-scale models fabricated using the laser lithographic modeling method from computed tomography data. A titanium plate was then fixed with screws on the implant before implantation, and then the temporalis muscle was refixed to the holes at both ends of the plate. The application of this technique reduced the hospitalization time and achieved good results esthetically.

Analysis of microsatellite instability and loss of heterozygosity in uterine endometrial adenocarcinoma.

Microsatellite instability (MSI) and loss of heterozygosity (LOH) were examined in 60 cases of uterine endometrial adenocarcinoma, using 13 microsatellite markers. In non-Smad-related regions, MSI and LOH were noted in 13 of 60 (21.7%) and in 20 of 60 (33.3%) cases, respectively. Genetic alternation of TGF-beta RII was noted in 1 of 60 cases (1.7%). The frequency of MSI and LOH was highest in Stages III and IV, respectively. Cases with G2 carcinoma showed the highest frequency, but LOH frequency did not differ among G1, G2, and G3 carcinoma cases. In Smad-related microsatellite regions, MSI and LOH were noted in 10 of 60 (16.7%) and in 12 of 60 (20.0%) cases, respectively. The frequency of MSI and LOH was highest in Stages III and IV, respectively. LOH was seen only in the Smad2 gene but not in the Smad4 gene. Our results suggest that the alterations in MSI and LOH were associated with middle and late stages of carcinogenesis of endometrial carcinoma. Both MSI and LOH tended to show an association with moderate to severe atypia of carcinoma. Our results also suggest that genetic alteration of the Smad2 gene is more responsible for endometrial carcinogenesis than that of the Smad4 gene. However, the TGF-beta type II receptor gene was considered a minor target of genetic instability in endometrial carcinogenesis.

Reconstruction of a full-thickness defect of the chest wall caused by friction burn using a combined myocutaneous flap of teres major and latissimus dorsi muscles.

This report describes the therapeutic course of a case of deep burns caused by friction heat generated over a long contact time by a rotating tractor wheel. The burn was accompanied by a full-thickness defect of the chest wall, which we treated with a combined myocutaneous flap of teres major and latissimus dorsi muscles with a large skin flap. Our therapeutic concept of this case is discussed. Based on the postoperative course of this case, we think a combined myocutaneous flap of teres major and latissimus dorsi muscles with two nourishing vessels as an alternative is a very useful, safe, and secure method for the treatment of cases with axillary damages which require one-stage and stable reconstruction, like our patient.

Effects of a collagen matrix containing prostaglandin E(1) on wound contraction.

In this study, we evaluated the effectiveness of prostaglandin (PG) E(1) in inhibiting wound contraction, both alone and in combination with collagen matrix, using a in vivo full thickness skin defect model. To clarify the mechanisms involved in this inhibition we also used a fibroblast-populated collagen gel contraction in vitro model. We demonstrated that collagen matrix alone significantly inhibited wound contraction PG E(1) alone did not. Interestingly, their combination was much more effective than either collagen matrix or PG E(1) alone, a finding which was also supported by histopathological examination. Wounds treated with collagen matrix, but not control wounds, showed horizontal rearrangement of collagen fibers in the dermal part as well as evidence of active fibroblast proliferation which was not observed in scar regions surrounded by normal dermis. With the fibroblast-populated collagen gel contraction in vitro model, we found that PG E(1) significantly inhibited contraction at a high dose. It was concluded that collagen matrix combined with PG E(1) is effective for preventing contracture producing so called neodermis than collagen matrix alone, which remains one of the most challenging problems in treating full thickness type wounds.

Development of a chronic skin defect model and a study of cytokine secretion using the model.

In this study, we established a delayed healing chronic type wound model in order to investigate the etiology of chronic wound healing, including wound contraction. Establishment of the model was important for clarification of the mechanism(s) of chronic wound healing and wound contraction and for use in evaluating therapeutic efficacy. A pedicled skin flap was raised beneath the panniculus carnosus membrane on the backs of mice, and after the loose connective tissue at the base of the flap was completely removed surgically, the flap was replaced and sutured. Seven days after surgery, a full-thickness defect measuring 1.5 x 1.5 cm was made in the center of the skin flap. At that time, a defect of the same size, including the panniculus carnosus membrane, was made in another group of mice as controls, and changes with time in wound area were compared between the two groups. The exudate retained on the wound surface was collected, and various cytokines contained in the exudate were measured. In the control group, the wound rapidly contracted and almost completely epithelialized and closed 21 days after surgery. On the other hand, the wound area was significantly larger in the delayed model than in the control animals during the observation period, revealing a delay in wound contraction. Transforming growth factor-beta, interleukin-1beta, and tumor necrosis factor-alpha in the exudates from the wound of the model were significantly higher than in those of the control group, whereas interleukin-6 was low in the model. From these results, it was concluded that this model could be a useful experimental system for studies on wound contraction as well as clarifying the mechanism of so called chronic type wounds.

Stimulatory effects of dibutyryl cyclic adenosine monophosphate on cytokine production by keratinocytes and fibroblasts.

BACKGROUND: Clinical studies have shown that ointment containing dibutyryl cyclic adenosine monophosphate (DBcAMP) promotes wound healing. OBJECTIVES: We aimed to elucidate the mechanisms of the beneficial effect of DBcAMP in wound healing. METHODS: An investigation was made of the effects of DBcAMP on in vitro cytokine release from cultured keratinocytes and fibroblasts derived from normal human skin. RESULTS: DBcAMP stimulated keratinocyte proliferation through increased interleukin (IL)-6 production by fibroblasts, and transiently enhanced production of transforming growth factor (TGF)-beta1 by fibroblasts at an early stage of incubation. DBcAMP also stimulated fibroblast proliferation, resulting in further increases in IL-6 and TGF-beta1. CONCLUSIONS: We conclude that this series of stimulative actions on cytokine secretion, together with the facilitation of cell proliferation, contribute to the effects of DBcAMP on the healing of skin ulcers.

Histopathological changes in the hair follicle after irradiation of long-pulse alexandrite laser equipped with a cooling device.

Several laser systems are currently used for epilation. However, the optimal parameters and treatment protocols remain largely unknown. In this study, the histopathological changes in the hair follicles after long pulsed alexandrite laser irradiation are discussed and the clinical application of irradiation energy at the time of treatment is described. The laser used in this study is equipped with a computer controlled cooling device. A histopathological study was performed to compare the differences in the degree of degeneration in the epidermis and follicles treated with and without the cooling device. In comparison with normal hair papilla, in the laser irradiated skin, injury of melanin containing cells and hair shafts and external root-sheaths in the periphery were observed, while the epidermis was completely protected by the cooling device. The condition of the hair papilla of the tissue irradiated at a fluence of 25 J/cm2 with a spot diameter of 15 mm and 20 J/cm2, with a spot diameter of 18 mm were investigated thoroughly. Swollen papilla and selective destruction of the site where melanocytes were present were observed. The results of this study strongly indicate the efficacy of a long-pulsed alexandrite laser equipped with a computer controlled cooling device for clinical depilation.

Non-traumatic gas gangrene in the abdomen: report of six autopsy cases.

Six autopsy cases of non-traumatic gas gangrene in the abdomen are reported. Five of the six were caused by clostridia, as identified by culture or histology. There were associated underlying diseases, such as alcoholism, liver cirrhosis, diabetes mellitus, and malignant disease. Three of the six patients had gas gangrene in the liver. Bacterial proliferation and gas accumulation were found in the sinusoids of the liver, and congestion and edema with extensive gas embolism were found in the lungs. Pulmonary gas embolism was considered to be the direct cause of death in these three patients. The other three patients had intestinal clostridial gas gangrene, with alcoholism as an underlying condition. None of the six patients was clinically diagnosed as having gas gangrene. We suggest that gas gangrene should be considered in any patient with abdominal infection. A review of 19 autopsy cases of gas gangrene in the abdomen reported in the Japanese literature is also presented.

Enhanced expression of caspase-3 in hypertrophic scars and keloid: induction of caspase-3 and apoptosis in keloid fibroblasts in vitro.

Recent studies have suggested that the regulation of apoptosis during wound healing is important in scar establishment and development of pathological scarring. To examine the phenomenon of apoptosis and its involvement in the process of pathological scarring, we immunohistochemically quantified differential levels of expression of caspase-3 and -2, which are activated during apoptosis in vitro, in surgical resected scar tissues. We divided 33 cases of normally healed flat scars and 18 cases of pathological scars (15 cases of hypertrophic scars and 3 cases of keloid) into three groups (S1 = <10 months' duration; S2 = 10 to 40 months' duration; and S3 = >40 months' duration) according to the duration of scar. In all three groups examined, the semiquantitative scores for caspase-3 staining were significantly higher for the combination of hypertrophic scars and keloid as a group compared with normally healed flat scars, suggesting reduced cell survival and increased apoptotic cell death in hypertrophic scars and keloid. Apoptosis and caspase proteolytic activities were examined in vitro using two flat scar-derived fibroblast lines (FSFB-1 and -2) and two keloid-derived fibroblast lines (KFB-1 and -2). After 24 hours of serum deprivation, apoptotic cells were significantly increased in both KFB lines, whereas serum deprivation of FSFB-1 cells did not result in a significant increase in apoptotic cell number. After serum deprivation, significant increases in caspase-3 proteolytic activities were detected in both KFB lines compared with both FSFB lines. In contrast, no significant differences with caspase-8 activity were observed between similarly treated KFB and FSFB lines. Furthermore, serum deprivation-induced apoptosis of KFB-2 cells was significantly inhibited by the caspase-3 inhibitor Ac-Asp-Glu-Val-Asp-fluoromethyl ketone (DEVD-FMK), indicating that caspase-3 is important for serum deprivation-induced apoptosis in KFB-2 cells. Considering the role of caspase-3 as a key effector molecule in the execution of apoptotic stimuli, our results suggested that enhanced expression of caspase-3 in hypertrophic scars and keloid induces apoptosis of fibroblasts, which may play a role in the process of pathological scarring.

Phacomatosis pigmentovascularis type IIa successfully treated with two types of laser therapy.

We describe a 28-year-old Japanese woman with phacomatosis pigmentovascularis type IIa who was treated by 27 sessions of Q-switched ruby laser irradiation to the site of dermal melanosis on her face and three sessions of dye laser irradiation to the port-wine stain on her left cheek. This is the first report of the successful treatment of a cutaneous lesion in a patient with phacomatosis pigmentovascularis. As the outcome of the treatments was excellent, we conclude that phacomatosis pigmentovascularis type IIa can be treated successfully by the combination of the two types of laser therapy.

New surgical technique for macrostomia repair with two triangular flaps.

Our new surgical procedure with two triangular flaps for macrostomia repair allows us to achieve all three therapeutic goals, including formation of symmetric lips and commissures of the mouth, reconstruction of the orbicularis muscle of mouth to restore labial function, and reconstruction of the commissure of the mouth with a natural looking contour. Furthermore, the position of the commissure of the mouth can be adjusted intraoperatively according to the extent of macrostomia. As reported here, our method provides very satisfactory clinical results and is relatively easy to perform. Thus, we believe that our method can serve as a standard for the surgical treatment of macrostomia.

Evaluation of a high density polyethylene fixing system for hydroxyapatite ceramic implants.

A fixing system made of high density polyethylene (mini ROC fastener system, Innovasive Devices Inc., Marlborough, MA, USA) was applied to artificially porous hydroxyapatite (HAP) implants. Their fixing ability was assessed with pull-out tests and a preliminary study was done to determine the most suitable drill hole diameter and depth. Effectiveness of the combined use of drill-free titanium screws (Martin GmbH & Co. Ltd., Tuttlingen, Germany) and the mini ROC fastener system was also evaluated. The pull-out strength of the system differed according to the hole diameter and depth of insertion. The strongest physical strength was obtained with holes 2.10 mm in diameter and 6 mm in depth. If inserted under optimum conditions, the mini ROC fastener system was deemed to have adequate fixing ability for clinical applications pull-out strength more than 7 kgf. In addition, the combined use of a drill-free screw for microplate with the mini ROC fastener system had a pull-out strength of around 10 kgf which was superior to the mini ROC fastener system alone. The mini ROC fastener system is best suited to fix HAP implants to the soft tissues such as muscle, tendon or periosteal tissue as well as for plate fixation when used with drill-free screws. The fact that effective fixing was achieved should result in a further increase in the clinical use of artificial HAP implants.