[A case of an elderly SLE patient associated with acute renal failure]

It has been described that a rapid worsening in renal function is uncommon in the elderly patient with lupus nephritis. We report a case of a 76-year-old man with rapidly progressive lupus nephritis. On admission, laboratory studies revealed massive proteinuria, telescoped urine, thrombocytopenia and azotemia. Hypocomplementemia and the positive presence of anti-DNA antibody and lupus anticoagulant were also noted. Because of a rapid deterioration of renal function, he was started on a regimen of steroid pulse therapy and plasmapheresis. Serum levels of complements gradually increased after initiation of these treatments, and three weeks later, improvements of renal function and nephrotic syndrome were obtained. A renal biopsy specimen taken five months after admission showed diffuse membranous glomerulonephritis. In addition, we examined renal arterial blood flow with Doppler ultrasound, and significant improvements of the velocity and pulsatility were observed during recovery of the renal function.

[Immunohistochemical study on the distribution of CGRP-containing nerve fibers in the PCB poisoned rats with experimental periodontitis]

We have studied immunocytochemically the distribution of CGRP-containing nerve fibers in the PCB poisoned rats introducing experimental periodontitis. The results obtained were as follows. In the PCB poisoned rats, some specimens obtained from periodontitis-affected sites showed a slight increase in both the intensity of nerve staining and the nerve sprouting. However, no discernible difference in the occurrence and the distribution of nerves has been demonstrated between the PCB poisoned rats and clinically healthy rats. Further studies are needed to confirm the effects of PCBs on the initiation and progression of periodontitis.

Centrally administered neuropeptide Y (NPY) inhibits gastric emptying and intestinal transit in the rat

Neuropeptide Y is distributed abundantly not only in the brain, but also in the gastrointestinal tract and suppresses intestinal muscle contraction in isolated muscle preparations. The purpose of the present study was to determine whether centrally administered neuropeptide Y modulated gastric emptying and intestinal transit in conscious rats. Graded doses of neuropeptide Y were administered intracisternally 1 min before ingestion of test meals through an oral tube. Four hours after ingestion of 60 Amberlite pellets, the rats were sacrificed and residual pellets in the stomach and the small intestine segments were counted to calculate the solid meal transit rate. The liquid meal transit rate was calculated 1 hr after 0.07% phenol red ingestion by determining the residual phenol red in the stomach and the small intestine segments. Neuropeptide Y elicited potent suppression of gastric emptying and intestinal transit of both solid and liquid meals. Pretreatment with propranolol antagonized, whereas phentolamine did not affect, the suppressive effect of central neuropeptide Y. Although carbachol blocked the effects of neuropeptide Y, neither atropine nor hexamethonium altered the actions of neuropeptide Y. In conclusion, centrally administered neuropeptide Y strongly inhibited gastrointestinal transit by stimulating a beta-adrenergic pathway.

Doppler sonographic measurement of phasic renal artery blood flow velocity in patients with chronic glomerulonephritis

The phasic arterial blood flow velocity at the renal hilus was measured by Doppler sonography in 25 healthy subjects and 78 patients with chronic glomerulonephritis. Doppler velocity waveform was analyzed to give peak systolic velocity (S), end-diastolic velocity (D), resistive index (RI), and pulsatility index (PI). Creatinine clearance correlated with S (r = 0.76), D (r = 0.80), RI (r = -0.74), and PI (r = -0.85). Color Doppler sonography facilitated the detection of blood flow and permitted the measurement of absolute blood flow velocity, which previously had been difficult to determine. These results suggest that renal arterial blood flow as detected by Doppler ultrasonography may be useful for noninvasive, direct, rapid, and simple evaluation of renal function, although various modifying factors also need to be considered.

Formation of Nanometer-Scale Grooves in Silicon with a Scanning Tunneling Microscope

Grooves a few nanometers wide can be formed on a Si(111) surface with a scanning tunneling microscope when the tip is above a critical voltage. This may provide a promising approach to nanodevice fabrication. The dependence of the critical voltage on tunneling current, tip polarity, and tip material was studied with silver, gold, platinum, and tungsten tips. The results are consistent with field emission of positive and negative silicon ions. The variation of critical voltage with current is explained quantitatively by a simple tunneling equation that includes the effect of the contact potential between tip and sample.

Alumina versus polyethylene in total knee arthroplasty

The cementless alumina total knee prosthesis, which uses alumina in the portions coming in contact with the bone and a combination of alumina and ultra-high molecular-weight polyethylene (UHMWPE) in the sliding portions, is referred to as a total condylar. Alumina total knee arthroplasty was performed on 137 patients, including 103 rheumatoid arthritis (RA) and 34 osteoarthrosis (OA) patients, from January 1982 to February 1985. The follow-up period was seven years 11 months and four years ten months, respectively. At follow-up evaluation, 108 patients were available for clinical and roentgenographic examinations, amounting to a 79% follow-up rate. At follow-up examination, 67 joints (62%) were completely pain free and 28 joints (26%) caused slight pain on bearing weight. Walking ability was recovered moderately in RA and markedly in OA. In RA, 14 of 84 knees were cemented and one knee was treated with loosening. Of 72 cementless implantations, 55 sustained displacing distally and one sustained loosening in the tibia, whereas 31 sustained displacing proximally and six sustained loosening in the femur. In OA, 21 cementless knees had 17 displacings in the tibia, and ten displacings and two loosenings in the femur. Scanning electron microscopy (SEM) observation of the UHMWPE surface in tibial plates revealed smoothing and burnishing. Alumina is far superior to metal for the sliding part, although it is not always best for the portion in contact with the bone. To resolve these problems, for cementless fixation, anchoring portions of Ti alloy and alumina implants were covered with beads and coated with hydroxyapatite. For cement fixation, "the interface bioactive bone cement technique" interposing hydroxyapatite granules between bone and cement was performed.

A clinical study on the control of dental plaque using an electronic toothbrush with piezo-electric element

A double-blind clinical study was conducted to compare the plaque-removing efficiency of a newly designed electronic toothbrush to that of a placebo, conventional toothbrush. Twenty-six students were selected at Asahi University, School of Dentistry in Japan. The subjects were divided into two groups, one which used the electronic toothbrush and the other which used the placebo toothbrush. The subjects served as their own control by brushing manually for 3 minutes. The plaque elimination ratio, however, showed no significant difference between the testing and the control group. The main conclusion of this study is that an electronic toothbrush is not superior to the conventional toothbrush.

Long-term occlusal guidance of a severely intoxicated patient with yusho (PCB poisoning): a case report

The peculiar dentoorofacial characteristics and 12 years of interdisciplinary management of a patient who was severely intoxicated with the man-made chemical polychlorinated biphenyls (PCBs) are described in this case report. Cephalometric measurements showed that the SNA and SNB angles were reduced but that the developments in height and skeletal maturity were in normal ranges. Gingival hyperpigmentation that was caused by high blood PCB concentration was extremely slow to fade. A cystic mass, diffused trabeculae, and irregular calcification, which were shown on the radiograph and which were caused by high blood levels of PCB, changed gradually. However, the patient had periodontal disease because of horizontal alveolar bone resorption and a deep periodontal pocket, despite good plaque control. After the PCB poisoning the tooth roots were hypoplastic and dilacerated. One root was extracted because of chronic periodontitis. Some teeth were impacted, malposed, or ankylosed.

Successful resection of pheochromocytoma in a hemodialysis patient

A 45-year-old woman with a pheochromocytoma who had been on regular hemodialysis for 4 years and underwent successful surgery is described. Careful preoperative management, including the use of prazosin and weight control, was carried out to prevent severe intraoperative and postoperative cardiovascular complications. Prazosin was given at an initial dose of 0.5 mg/day, and the dosage was increased to 20 mg/day prior to surgery. The increase in intravascular volume led to a gain of 3 kg in body weight. No deterioration of the cardiovascular or respiratory function was caused by these maneuvers, and surgery was performed without significant complications except for a rapid rise of blood pressure during tumor resection. To our knowledge, only one similar case report could be found in the English literature.

An interleukin-1 inhibitor in gingival crevicular fluid of patients with chronic inflammatory periodontal disease

The gingival crevicular fluid of a patient(s) with marginal periodontal disease contained an activity inhibitory to interleukin-1 (IL-1). The inhibitory activity could be detected after the depletion of IL-1 alpha by the use of a specific antibody (anti-human recombinant IL-1 alpha monoclonal antibody)-conjugated Sepharose column. The inhibitory activity was not due to a toxic effect on the thymocytes since IL-1 alpha-depleted gingival crevicular fluid did not affect the incorporation of [3H]thymidine in either the presence or absence of concanavalin A. The inhibitory activity was exerted against both IL-1 alpha and IL-1 beta. The inhibitory factor did not have any effect on IL-2-induced proliferation of concanavalin A-activated spleen cells. The inhibitor was heat labile. Gel filtration on a Superose 12 column revealed the IL-1 inhibitor to have two major peaks, one in the molecular size range of 12 to 14 kDa and the other below a molecular size of 10 kDa.

Penetration, clearance and retention of antigen en route from the gingival sulcus to the draining lymph node of rats

We investigated the penetration and clearance of antigen in the rat gingiva and the antigen-specific antibody response in the draining lymph nodes. Rats were primarily immunized into the alveolar submucosa with horseradish peroxidase (HRP) in complete Freund's adjuvant. Ultrastructural demonstration of antigen and specific antibody was performed by incubation of cryosections in an HRP solution, followed by peroxidase cytochemistry. Anti-HRP antibody-containing cells were observed in the draining lymph nodes from 2 to 9 weeks after immunization. The bulk of these cells were located in the medullary cords. The extracellular antibody and antibody-containing cells were also found in germinal centers (GCs) from 3 to 9 wk, and 3 wk, respectively, after immunization. The results suggest that the specific antibody response was most enhanced 3 wk after primary immunization. Therefore, at this time we further challenged rats with the topical application of HRP to the gingival sulcus. The results showed that antigen penetrated through the junctional epithelium into the underlying connective tissue and from here was cleared by macrophages or via the lymphatics. In the draining lymph nodes, antigen first appeared in the subcapsular sinus and eventually became retained within GCs. Between 3 and 5 days, the GCs of challenged rats contained more mature-type anti-HRP antibody-containing cells than those of non-challenged rats. The sequence of events observed suggests that antigen challenge applied topically to the gingival sulcus can induce the active GC reaction in the draining lymph nodes of immunized rats.

Centrally administered NPY stimulated gastric acid and pepsin secretion by a vagally mediated mechanism

We investigated the possible roles of centrally administered neuropeptide Y (NPY) on gastric secretion, serum gastrin levels and gastric mucosal blood flow in anesthetized rats. Centrally administered NPY dose-dependently stimulated gastric acid and pepsin secretion. The stimulatory effect of intracerebroventricular administration of NPY was more potent than that of intracisternal administration. Centrally administered NPY also increased gastric secretion in the central noradrenaline depleted rats. In contrast, intravenously administered NPY had no influence on gastric secretion. These stimulatory effects were abolished by vagotomy or atropine pretreatment. The serum gastrin levels did not change after central NPY injection. Although intravenously administered NPY slightly increased gastric mucosal blood flow, centrally administered NPY slightly diminished gastric mucosal blood flow. These results indicate that centrally administered NPY markedly influences gastric functions in the rat.

A histochemical study of bone remodeling during experimental apical periodontitis in rats

An apical periodontitis experimental model was produced by means of opening the pulp chamber of the mandibular first molar in Wistar strain rats. In particular, the behavior of bone tissue in the vicinity of the root apex was investigated histochemically, ultrastructurally, and quantitatively. In addition, in order to demonstrate the effects of prostaglandin on the formation process of apical periodontitis, we examined the effects of indomethacin on bone remodeling during experimental apical periodontitis. These experiments suggested that prostaglandin may stimulate osteoclastic bone resorption and that the relationship between bone resorption and formation in apical periodontitis is a coupling phenomenon.