Occlusal trauma accelerates attachment loss at the onset of experimental periodontitis in rats.

BACKGROUND AND OBJECTIVE: Occlusal trauma is an important factor that influences the progression of periodontitis, but it is unclear whether occlusal trauma influences periodontal destruction at the onset of periodontitis. We established an experimental periodontitis model with both site-specific loss of attachment and alveolar bone resorption. The purpose of the present study was to investigate the effects of occlusal trauma on periodontal destruction, particularly loss of attachment, at the onset of experimental periodontitis. MATERIAL AND METHODS: Sixty rats were used in the present study. Forty-eight rats immunized with lipopolysaccharide (LPS) intraperitoneally were divided into four groups. In the trauma (T) group, occlusal trauma was induced by placing an excessively high metal wire in the occlusal surface of the mandibular right first molar. In the inflammation (I) group, periodontal inflammation was induced by topical application of LPS into the palatal gingival sulcus of maxillary right first molars. In the trauma + inflammation (T+I) group, both trauma and periodontal inflammation were simultaneously induced. The PBS group was administered phosphate-buffered saline only. Another 12 nonimmunized rats (the n-(T+I) group) were treated as described for the T+I group. All rats were killed after 5 or 10 d, and their maxillary first molars with surrounding tissues were observed histopathologically. Loss of attachment and osteoclasts on the alveolar bone crest were investigated histopathologically. To detect immune complexes, immunohistological staining for C1qB was performed. Collagen fibers were also observed using the picrosirius red-polarization method. RESULTS: There were significant increases in loss of attachment and in the number of osteoclasts in the T+I group compared with the other groups. Moreover, widespread distribution of immune complexes was observed in the T + I group, and collagen fibers oriented from the root surface to the alveolar bone crest had partially disappeared in the T, T+I and n-(T+I) groups. CONCLUSION: When inflammation was combined with occlusal trauma, immune complexes were confirmed in more expanding areas than in the area of the I group without occlusal trauma, and loss of attachment at the onset of experimental periodontitis was increased. Damage of collagen fibers by occlusal trauma may elevate the permeability of the antigen through the tissue and result in expansion of the area of immune-complex formation and accelerating inflammatory reaction. The periodontal tissue destruction was thus greater in the T+I group than in the I group.

Gram-positive bacteria as an antigen topically applied into gingival sulcus of immunized rat accelerates periodontal destruction.

BACKGROUND AND OBJECTIVE: Periodontitis is generally accepted to relate to gram-negative bacteria, and the host defense system influences its onset and progression. However, little is known about the relation between gram-positive bacteria and periodontitis. In this study, we topically applied gram-positive and gram-negative bacterial suspensions to the gingival sulcus in rats after immunization, and then histopathologically examined their influence on periodontal destruction. MATERIALS AND METHODS: Rats previously immunized with heat-treated and sonicated Staphylococcus aureus or Aggregatibacter actinomycetemcomitans were used as immunized groups. The non-immunized group received only sterile phosphate-buffered saline. In each animal, S. aureus or A. actinomycetemcomitans suspension was applied topically to the palatal gingival sulcus of first molars every 24 h for 10 d. Blood samples were collected and the serum level of anti-S. aureus or anti-A. actinomycetemcomitans immunoglobulin G (IgG) antibodies was determined by enzyme-linked immunosorbent assay. The first molar regions were resected and observed histopathologically. Osteoclasts were stained with tartrate-resistant acid phosphatase (TRAP). The formation of immune complexes was confirmed by immunohistological staining of C1qB. RESULTS: Serum levels of anti-S. aureus and anti-A. actinomycetemcomitans IgG antibodies in the immunized groups were significantly higher than those in the non-immunized groups were. The loss of attachment, increase in apical migration of the junctional epithelium, and decreases in alveolar bone level and number of TRAP-positive multinuclear cells in each immunized group were significantly greater than in each non-immunized group. The presence of C1qB was observed in the junctional epithelium and adjacent connective tissue in the immunized groups. CONCLUSIONS: Heat-treated and sonicated S. aureus and A. actinomycetemcomitans induced attachment loss in rats immunized with their suspensions. Our results suggest that not only gram-negative but also gram-positive bacteria are able to induce periodontal destruction.

Topical application of lipopolysaccharide into gingival sulcus promotes periodontal destruction in rats immunized with lipopolysaccharide.

BACKGROUND AND OBJECTIVE: The causes of periodontitis are bacteria and the host immune system, but the role of the immune system in the onset and progression of periodontal disease is still unclear. Our previous report showed that the formation of an immune complex in the gingival sulcus induces periodontal destruction. This study was carried out to investigate how the immune system, particularly immunization, is involved in periodontal destruction. MATERIAL AND METHODS: Animals immunized intraperitoneally with lipopolysaccharide (LPS) were used as the immunized group. The nonimmunized group received only phosphate-buffered saline. LPS was applied daily onto the palatal gingival sulcus in both groups 1 d after the booster injection. Serum levels of anti-LPS IgG were determined. Loss of attachment and the level of alveolar bone were histopathologically and histometrically investigated. RANKL-bearing cells and the expression of C1qB were immunohistologically evaluated. RESULTS: The serum levels of anti-LPS IgG were elevated in the early experimental period in the immunized group. There were significant increases in loss of attachment, level of alveolar bone and the number of RANKL-bearing cells in the immunized group. C1qB was observed in the junctional epithelium and adjacent connective tissue. The nonimmunized group showed similar findings at and after the time when the serum level of anti-LPS IgG was elevated. CONCLUSION: Topical application of LPS as an antigen induced periodontal destruction when the serum level of anti-LPS IgG was elevated in rats immunized with LPS. The presence of C1qB suggests that the formation of immune complexes is involved in this destruction.

The formation of immune complexes is involved in the acute phase of periodontal destruction in rats.

BACKGROUND AND OBJECTIVE: Loss of clinical attachment and alveolar bone destruction are major symptoms of periodontitis, caused by not only the destructive effect of periodontopathic bacteria but also the overactive response of the host immune system against periodontal pathogens. The details of the participation of the immune system in the onset and progression of periodontitis are unclear. In this study, we attempted to determine whether the host immune system, and in particular the formation of immune complexes, is involved in the periodontal destruction. MATERIAL AND METHODS: We applied ovalbumin or lipopolysaccharide (LPS) as antigens and their specific immunoglobulin G (IgG) antibodies purified from rat serum to rat gingival sulcus alternately. Loss of attachment, alveolar bone destruction and the numbers of inflammatory cells infiltrating the periodontal tissue and osteoclasts on the alveolar bone surface were investigated histometrically. The formation of immune complex was confirmed by immunohistological staining of complement C1qB. RESULTS: Loss of attachment and the presence of C1qB were observed histopathologically in both experimental groups. The group that had been treated with LPS and anti-LPS IgG showed greater loss of attachment. The number of inflammatory cells in the periodontal tissue was increased in both experimental groups, while osteoclasts at the alveolar bone crest were observed only in the group that had been treated with LPS and anti-LPS IgG. CONCLUSION: In the present study, we showed that the formation of immune complex appears to be involved in the acute phase of periodontal destruction and that the biological activity of antigens is also important.

Readout signals calculated for near-field optical pickups with land and groove recording.

Optical disk readout signals with a solid immersion lens (SIL) and the land-groove recording technique are calculated by use of a simplified vector-diffraction theory. In this method the full vector-diffraction theory is applied to calculate the diffracted light from the initial state of the disk, and the light scattered from the recorded marks is regarded as a perturbation. Using this method, we confirmed that the land-groove recording technique is effective as a means of cross-talk reduction even when the numerical aperture is more than 1. However, the top surface of the disk under the SIL must be flat, or the readout signal from marks recorded on a groove decays when the optical depth of the groove is greater than lambda/8.

High-density optical recording using a solid immersion lens.

A solid immersion lens attached to a conventional objective increases the effective numerical aperture (NA(eff)) of an optical pickup and yields an areal recording density proportional to (NA(eff))(2). One version of this device, with an effective (NA(eff)) of 1.7, should be capable of very high density storage but would probably need a sealed system. Another simple configuration enables the use of this method for optical data storage in an unsealed environment and extends the spatial cutoff frequency 1.5 times. Experiments with these devices are compared with the full vector field theory of this type of imaging system.

Effects of isosorbide dinitrate on thromboxane A2 synthesis in carbon dioxide exposed platelets.

Isosorbide dinitrate (Nitorol R, 100 nmol/l) blocked an increase in thromboxane B2 concentration in human platelet-rich plasma caused by exposure to high CO2 tension, in the presence of arachidonic acid. Thromboxane B2 concentrations obtained at 1 or 2 mmol/l or arachidonic acid were not influenced by isosorbide dinitrate at low CO2 tension. Inhibitory action of isosorbide dinitrate on the thromboxane A2 synthesis appears to have a close relation to the site of CO2 action.

Isosorbide dinitrate blocks thromboxane synthesis caused by CO2 in dog heart-lung preparation.

Effects of isosorbide dinitrate (ISDN) on coronary flow and arterial prostaglandin (PG) concentrations were investigated, using dog heart-lung preparations. Two kinds of gases (low and high CO2 gases) were used for the artificial respiration. Low CO2 gas contained 55% O2 and 0.2% CO2, whereas high CO2 gas contained 55% O2 and 8% CO2. Administration of ISDN into a blood reservoir at high CO2 caused an increase in coronary sinus blood flow, which was blocked by indomethacin, but not at low CO2. In the absence of ISDN, the arterial concentration of thromboxane (TX) B2 was larger at high CO2 than at low CO2. ISDN attenuated such an increase in TXB2 concentration caused by CO2. The arterial concentration of 6-keto PGF1 alpha was altered by neither CO2 nor ISDN, but slightly increased with time. Indomethacin lowered the concentrations of 6-keto PGF1 alpha and TXB2. These results suggested that the arterial CO2 tension enhanced the TXA2 synthesis and that ISDN inhibited such a relation between CO2 and TXA2 synthesis. Additionally, the vasodilatory effects of PGI2 was enhanced by elevating the arterial CO2 tension. Thus, the increase in canine coronary flow at high CO2 in the presence of ISDN may be related to the inhibitory effects of ISDN on the TXA2 synthesis enhanced by the high arterial CO2 tension and the facilitatory effects of CO2 on the PGI2-induced vasodilation.

[Superselective transarterial embolisation of the hypogastric artery and it's branches in the management of unresectable intrapelvic malignant tumors with minor surgical procedures].

Three patients with recurrent uterine cancer, unresectable rectal cancer, and recurrent rectal cancer in the pelvis were treated by percutaneous superselective transarterial embolisation (TAE) of the hypogastric artery and it's branches with ethanol or gelatin sponge particles. TAE was performed for the control of life-threatening hemorrhage, severe pain and the diminishing tumor's bulk. In addition to conservative cares, this TAE needed minor surgical procedures such as urinary diversion, colostomy and drainage of abdominal abscess just when urinary bladder's necrosis, rectosigmoidal necrosis and peritonitis would be expected before and after the TAE. One local hematoma in the site inserted catheter and right ischiadic nerve paralysis occurred by TAE. Two patients died on 6 days and 2 months after TAE, respectively, however one patient is still alive one year after the TAE without the growth of tumours. As a result, this TAE with minor surgical procedures is expected as a suitable treatment for the improvement of the survival and quality of life in the patients with unresectable intrapelvic tumors.

Intra-arterial long term infusion chemotherapy via transverse cervical artery for intra-abdominal malignancies.

An original method of intra-arterial catheter placement for long term infusion chemotherapy, using a transverse cervical artery, is described. Twelve patients with far advanced intra-abdominal malignancies, which precluded abdominal explorations, were catheterized and treated for prolonged periods. All patients were ambulated during the infusion chemotherapy and there were few catheter associated vascular complications. This method is a simple and safe procedure and seems superior to the conventional method using axillary or femoral arteries.

Latero-lateral end anastomosis for right hemicolectomy using staplers.

In seven patients undergoing right hemicolectomy for benign or malignant diseases, latero-lateral end anastomoses were made using stapling devices, LS (linear stapler) and GIA (gastrointestinal anastomosis). As no complications directly related to the anastomosis occurred, we conclude that anastomosis using stapling devices for right hemicolectomy is a safe and rapid procedure.

Coronary flow in heart-lung preparation affected by cardiopulmonary nerves and arterial PCO2.

Studies on coronary vasodilator drugs utilizing heart-lung preparations (HLP) have been disturbed by a spontaneous gradual increase in coronary blood flow. With the purpose of finding out what would cause the gradual increase, the time course of coronary sinus blood flow (CSBF) was investigated in 20 dog HLPs under four experimental conditions, according to whether cardiopulmonary nerves (CPN) were severed or not and whether CO2 content in the inspiratory gas was high (95% O2-5% CO2) or low (50% O2-50% room air). The gradual increase in CSBF was observed, accompanied by a significant increase in 6-ketoprostaglandin F1 alpha in the arterial blood, only when CPN were intact and, simultaneously, inspiratory CO2 was high. Nevertheless, the hemodynamic parameters, except CSBF, were almost similar under four conditions. These results suggested that CSBF in HLP could be affected via a synthesis and/or a release of prostaglandin I2 by the interaction of CPN and arterial PCO2.

[The concentration of ceftizoxime in serum and lung tissues and prophylaxis of postoperative infections].

There are few clinical reports about the concentration of ceftizoxime (CZX) in lung tissues. At present, clinically, we report the concentration of the drug in serum and lung tissues on 26 cases of chest disease and an effect of the drug on prophylaxis of postoperative pulmonary infections. Our results are the following; The peak concentration of CZX in serum is 54.7 micrograms/ml at 1 hour after starting drip infusion of CZX 1 g. The serum half-life of CZX (beta phase) is 2.07 hours. The concentration of CZX in lung tissues is from 43.6 to 78.7% of serum level. CZX is useful to prophylaxis of postoperative infections after thoracotomy, especially in case of administration of CZX 1 g just before operation. Eruption was found in 1 of 26 cases. However, no side effects of the drug are noticed in other 25 cases.

Basal cell carcinoma with lung metastasis.

A forty-seven year-old man had a small ulceration on his left cheek. The ulcer had a repeated crust formation following removal, for ten years. The patient found a hard tumor in the deep site of the ulcer and the tumor was resected. The pathological diagnosis was basal cell carcinoma. The metastases to the regional lymph nodes developed one year later and these lymph nodes were resected. The histological picture was the same as seen in the primary tumor. Lung metastasis occurred three years later. The tumor was resected and the pathological diagnosis was basal cell carcinoma. Multiple lung metastases developed one year later and massive hemoptysis led to a sudden death two years after the thoracotomy. Thirty-seven cases of basal cell carcinoma with lung metastases were reported in the literature. This case is the thirty-eighth case and the third occurrence in a Japanese.

Pelvic perfusion hyperthermia for advanced pelvic malignancies.

Pelvic perfusion hyperthermia (PPH) for malignant gynecologic diseases in the pelvis was performed for four hours with favorable results. Serial monitoring of chemotherapeutic drug concentrations in the blood, tissues and circuit showed that the drugs were satisfactorily incorporated into the tumor bearing area and that the systemic leak was minimal with no demonstrable systemic side effects. The temperature of the tumor was kept between 41.8 degrees C and 42.7 degrees C for over three hours. The esophageal temperature was maintained below 40 degrees C throughout the procedure. In one patient, there was an eighty percent reduction in tumor size and in the other, a complete regression of the tumor. We conclude that the PPH is a procedure that warrants further attention as an adjunct to cancer therapy for malignant pelvic tumors.

[Clinical evaluation of latamoxef, an oxacephem antibiotic with special reference to transport of latamoxef into the lung tissues and prevention of postoperative infections after thoracotomy].

There are few clinical reports about concentration of latamoxef (LMOX) in lung tissues. At present, clinically, we report a concentration of LMOX in serum and lung tissues on 21 patients of chest disease and a study of the administration schedule of LMOX for prophylaxis of postoperative infections on 31 operated patients with chest disease. Our results are the followings: The peak concentration of LMOX in serum is 77.4 micrograms/ml at 1 hour after starting drip infusion of LMOX 1 g. The concentration of LMOX in lung tissues is from 25% to 50% of serum level. LMOX is more useful to prophylaxis of postoperative infections after thoracotomy than cephalothin, especially in case of administration of LMOX just before operation. No side effects of LMOX are noted in our cases. LMOX has wide antibacterial activity against various clinical isolates and is useful to treatment of postoperative infections.