Computer-guided immediate provisionalization of anterior multiple adjacent implants: surgical and prosthodontic rationale.

Immediate implant restoration has gained popularity in recent years due in part to technological advancements that use computed tomographic images to simulate the actual clinical situation. This computer-assisted simulation enables clinicians to develop a comprehensive treatment plan that can be precisely executed in a timely manner. In the aesthetic zone, however, a successful outcome requires more than merely accurate implant placement. This article discusses the significance of site development for aesthetic implant restoration and describes a computer-guided immediate pro visionalization procedure and its surgical and prosthodontic rationale     

Substrate specificity of HMRZ-86 for β-lactamases,including extended-spectrum β-lactamases (ESBLs)

HMRZ-86 was designed as a new chromogenic cephalosporin to detect extended-spectrum β-lactamases (ESBLs) and similar evolved β-lactamases, such as metallo-β-lactamases, derepressed AmpC, and extended oxacillinase. We report here our investigation of the kinetic parameters of several types of β-lactamases to show the enzymatic characteristics of HMRZ-86. The Michaelis constant (K _m values of HMRZ-86 for ESBLs were twice to three and half times as high as those of nitrocefin, and the maximum velocity (Vmax) was one-fifth that of nitrocefin. The K _m and Vmax of HMRZ-86 for AmpC were both smaller than those of nitrocefin. The kinetic parameters of HMRZ-86 for metallo β-lactamase (MBL) were very variable, depending on the type of buffer solution used and the concentration of zinc ions. For MBL, the K _m values of HMRZ-86 were higher than those of nitrocefin, but the Vmax values were almost the same as those of nitrocefin. Although the chemical structure of HMRZ-86 is similar to that of nitrocefin, we think the enzymatic reactivities of the two entities for β-lactamases are very different.     

Prospective study of combined treatment with interferon‐alpha and active vitamin D3 for Japanese patients with metastatic renal cell carcinoma

Objectives: To assess the safety and efficacy of combined therapy with interferon‐alpha (INF‐α) and active vitamin D₃ for metastatic renal cell carcinoma (RCC). Methods: Sixteen patients with metastatic RCC were enrolled in this prospective study. All received oral alfacalcidol (1 µg once daily) and INF‐α (Sumiferon; 3 million units, three times a week). The primary endpoint was the response rate (defined as complete + partial remission). Secondary endpoints were cancer‐specific survival and toxicity. The median follow‐up period was 17 months (range: 5–49 months). Results: The median age of the patients was 68 years (range: 41–73 years). The sites of metastases were: lung in 13 patients, bone in one, lung and bone in one, and lung, bone, and lymph nodes in one. Four patients (25%) had a partial response (PR), 10 patients (62.5%) showed no change (NC), and two patients (12.5%) had progressive disease (PD). The median cancer‐specific survival time was 45 months. One patient had to discontinue vitamin D₃ because of hypercalcemia. Kaplan‐Meier survival analysis revealed that metastasis at the time of initial diagnosis and older than average age were significant predictors of poor survival (P < 0.05). Conclusions: Combined treatment with INF‐α and active vitamin D₃ has shown to be safe and effective for metastatic RCC patients.     

6‐Formylpterin protects retinal neurons from transient ischemia–reperfusion injury in rats: A morphological and immunohistochemical study

Neuroprotective effects of 6‐formylpterin (6FP) on transient retinal ischemia–reperfusion injury were evaluated in rats by means of counting the number of retinal ganglion cells, measuring the thicknesses of the inner plexiform and inner nuclear layers, and by immunohistochemical detection of apoptotic cells in the retina. Sixty‐one Sprague–Dawley rats (12 weeks, male, 295–330 g) were subjected to transient retinal ischemia–reperfusion by elevated intra‐ocular pressure (80 mmHg for 60 min). Intraperitoneal injection of 6FP (3.8 mg/kg) was performed before or after ischemia. The retina was histologically better preserved in rats with 6FP treatment than without 6FP treatment. 6FP showed more strong neuroprotective effects when it was administered before ischemia. The number of single‐stranded DNA‐positive cells in the retina also decreased remarkably in rats with 6FP treatment, especially when administered before ischemia. These results suggest that 6FP protects retinal neurons from transient ischemia–reperfusion injury, at least in part by inhibiting apoptotic cell death.     

Human chorionic gonadotropin in gastric carcinoma. A useful marker for bone metastasis

Twenty patients with bone metastases from gastric carcinoma resected during the 13 years from 1974 through 1987 were investigated in relation to the serum and tissue carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP) and human chorionic gonadotropin (hCG). The incidence of bone metastases was 2.1% (20/933). The serum AFP, CEA and hCG positive rates were found to be 14.3, 42.9 and 69.2% for patients with bone metastases and 18.3, 19.4 and 14.1% for those without bone metastases, respectively. In addition, the tissue AFP, CEA and hCG positive rates were 11.1, 100 and 77.8% for such patients with bone metastases, and 8.0, 80.8 and 21.1% for those without bone metastases. Only the serum and tissue hCG positive rate was significantly higher for the patients with bone metastases than those without bone metastases. The bone metastatic lesions were investigated for tissue hCG in four cases, and found to be positive in all the four bone lesions. In four of the patients with metachronous bone metastases, serum hCG levels were elevated before or at the time when bone metastases were diagnosed. Furthermore, serum hCG levels fell in response to chemotherapy or tumor resection. On the contrary, the serum AFP or CEA levels did not correlate with the clinical course in patients with bone metastases. These results indicate that the measurement of the tissue and serum hCG in patients with gastric carcinomas could be of extreme value in the search for bone metastases and the serum hCG level could be a useful marker for the prediction of bone metastases in gastric carcinoma.     

Hematological response to the new synthetic muramyl dipeptide derivative muroctasin after chemotherapy in patients with malignant lymphoma. A randomized crossover trial

A randomized crossover trial was performed in 20 patients receiving chemotherapy for malignant lymphoma. N2-[(N-acetylmuramoyl)-L-alanyl-D-isoglutaminyl]-N6-stearoyl-L-lysine (MDP-Lys(L18), muroctasin) at a dose of 200 micrograms was subcutaneously administered after one of two cycles of the same protocol. The administration was started on day 4 after the start of chemotherapy and continued for 10 days. The mean length from the start of chemotherapy to nadir of white blood cell (WBC) was not significantly different between the control and muroctasin cycles. The mean WBC and neutrophil counts at nadir of the control cycle were significantly lower than those at the same point of muroctasin cycle, respectively. A positive effect of muroctasin cycle, defined as WBC count at nadir being increased by 1,000/mm3, WBC count being increased by 1,000/mm3 on two points examined after nadir, or faster reach to nadir and faster recovery to normal range of WBC than in the control cycle, was observed in 7 (35%) of 20 patients. On the other hand, only one (5%) patient showed a superiority of the control cycle over the muroctasin cycle. Toxic effects of muroctasin were observed in 34.8% of patients, but were tolerable for most patients. These results show that muroctasin has a clinical efficacy in the restoration of leukopenia after chemotherapy.     

Three cases of single coronary artery

Single coronary artery has been considered a minor coronary anomaly without clinical importance. With the wide spread of coronary angiography, however, the disease has been reported to develop complications at a high rate, such as angina, myocardial infarction and arrhythmia. We report three patients with single coronary artery with several complications. Case 1: A 56-year-old woman having a past history of diabetes mellitus and myocardial infarction was admitted because of the recently developed frequent attacks of effort angina. Treadmill test was positive and thallium-201 exercise myocardial scintigraphy revealed redistribution in the lateral wall. Ascending aortogram suggested that the right coronary artery (RCA) arose from the left sinus of Valsalva. An injection into the right sinus of Valsalva revealed no coronary ostium. Selective left coronary angiogram resulted in the diagnosis of single coronary artery (Smith's type 2) with 90% stenosis in the left circumflex artery (LCX). Left ventriculogram showed hypokinesis in the anterolateral wall. PTCA performed on this patient revealed clinical and nucleomedical improvement. Case 2: A 48-year-old man experienced chest pain and syncope. Electrocardiogram revealed ST-elevations in II, I and a VF, sinus bradycardia and atrioventricular junctional rhythm. Angiography resulted in the diagnosis of single coronary artery (Smith's type 2) with 75% stenosis in the RCA. Ergonovine test was positive. Case 3: A 69-year-old man complained of chest pain. Electrocardiogram showed complete right bundle branch block, sinus bradycardia and atrioventricular junctional rhythm. Cardiac catheterization revealed that this was also a case of single coronary artery (Smith's type 2) with no significant stenosis.(ABSTRACT TRUNCATED AT 250 WORDS)