Effect of orally administered heat-killed Enterococcus faecalis FK-23 preparation on leukopenia in mice treated with cyclophosphamide

Cyclophosphamide (CY) treated mice were orally administered heat-killed Enterococcus faecalis FK-23 preparation (FK-23) to define the effect of FK-23 on leukopenia associated with chemotherapy. FK-23 had no inhibiting effect on CY induced leukopenia, whereas it augmented leukocyte reconstitution in CY-treated mice. The percentage of neutrophils increased in the mice orally given FK-23. Furthermore, an increase in a myeloid/erythroid ratio and neutrophilic lineages was found in bone marrow of FK-23 treated mice. These findings suggest that FK-23 may have a potent effect on the augmentation of leukocyte reconstituting capacity in patients receiving chemotherapy.

Retinal thickness change after focal laser treatment of diabetic macular oedema

Laser photocoagulation has been used successfully for the treatment of clinically significant macular oedema to reduce the risk of loss of vision in diabetic patients. A quantitative method for measuring retinal thickness was applied to 20 patients with diabetic macular oedema before and 4 months after focal laser treatment to assess the reduction in retinal thickening and its relation to visual acuity. The degree of thickening at each location, defined by thickness index, was determined relative to the corresponding average value in normal subjects. Comparison of quantitative retinal thickness measurements before and after treatment demonstrated that treatment at thickness indices of approximately 1.6 (60% thickening) has nearly 50% probability for reversal of thickening to within the normal range (< or = 1.3), whereas at thickness indices greater than 2.8 (180% thickening) there is less than 2.5% probability that reversal will occur. The level of foveal thickening before treatment strongly correlated with the degree of thickening after treatment. Most of the eyes with an improvement in visual acuity had a foveal thickness within the normal range at 4 months' follow up. These findings suggest that quantitative retinal thickness measurement provides an objective assessment of the degree of macular oedema and can be useful for monitoring the efficacy of focal laser treatment in reducing the thickening and relating the latter to visual outcome.

[Development of real-time CT fluoroscopy]

A new CT system that permits real-time monitoring of CT images was developed. Phantom and volunteer studies revealed that the images were displayed at a rate of six per second with a delay time of 0.83 second with clinically sufficient resolution (256 x 256) using the newly developed fast image processor and partial-reconstruction algorithm. The clinical trial of stereotactic aspiration of intracerebral hematoma was successful. The initial trial with CT fluoroscopy revealed potential usefulness of the system in biopsy and other CT-guided interventions.

Scleral plug of biodegradable polymers for controlled drug release in the vitreous

We designed a new device, a scleral plug, that releases drugs into the vitreous after being implanted and fixed at the pars plana. Use of the plug for provision of doxorubicin hydrochloride was evaluated in rabbits. The scleral plug (8.5 mg) was made of poly(lactic-glycolic acid) (molecular weight, 40,000 daltons) containing 1% doxorubicin. Vitreous concentrations of doxorubicin were measured after the implantation. In vitro studies showed that the plug released 26% of the drug during 4 weeks. In vivo studies demonstrated that the concentration in the vitreous humor was maintained at a therapeutic range for longer than 4 weeks. No substantial toxic reactions were observed by electroretinographic and histopathologic evaluations. Our findings suggested that a scleral plug made of biodegradable polymers is a promising device for a controlled drug-release system in the vitreous.

[Detectability of cerebral aneurysms and surrounding vessels by three-dimensional evaluation using helical scanning CT (HES-CT)]

Helical scanning CT (HES-CT) is a new technique to enable high-speed volumetric data acquisition. We have applied HES-CT to the diagnosis of cerebral vascular diseases. In our experience, the relationship between the scanning parameters of HES-CT and image quality was complex and reciprocal, so that optimization of the parameters according to the clinical demands was essential. We compared HES-CT with conventional cerebral angiography to determine the detectability of the aneurysm and surrounding vessels, and sought the optimal parameters to delineate small vessels. All aneurysms were detected in multiplanar reconstruction (MPR) images. The smallest one was 3 x 4 mm. MPR images were found to have some advantages over conventional cerebral angiography in delineation of intracranial aneurysms: 1) scanning was over in a short time (30s), 2) the relationship between the aneurysm and surrounding vessels was easily recognized, 3) the diameter of the neck could be measured, because the neck of the aneurysm and parent artery could be imaged on the same plane without overlapping another vessel, 4) calcified lesions on the aneurysmal wall were detected, and 5) HES-CT was done safety without arterial puncture. However, the detectability of unknown aneurysm was less than the detectability of known aneurysm in MPR images. The 180 degrees interpolation algorithm and 1 mm slice were effective in detecting small vessels. However, vessels with a diameter less than 1 mm could not be detected by HES-CT. HES-CT was considered to be useful as a supplementary examination to conventional angiography for the diagnosis of intracranial aneurysms.

Noninvasive visualization of the choriocapillaris and its dynamic filling

PURPOSE

The choroidal microvasculature and its circulation are inadequately assessed by presently available techniques. Laser-targeted delivery was applied to generate local, repetitive angiograms of the choriocapillaris in primates.

METHODS

Carboxyfluorescein was encapsulated in heat-sensitive liposomes and injected intravenously in monkeys. The liposome contents were then released locally in the choroid by application of a short heat pulse provided by an infrared laser. The bolus of dye spread rapidly downstream from the underlying arterioles into clusters of lobules. Video angiograms were generated with excitation illumination provided by an argon laser.

RESULTS

Laser-targeted delivery choroidal angiography performed on three monkeys indicated that the fluorescence was emitted mainly from the choriocapillaris. Clusters of irregular shape with well-defined margins were observed. Adjacent arteries typically supplied separate clusters that fit together like a jigsaw puzzle. The dynamic filling and emptying patterns, recorded at video rate, revealed that macular lobules were filled by a central arteriole and drained by a venous annulus. The average dye transit time through a lobule (n = 10) was 118 +/- 26 msec (mean +/- SD), and the dye transit velocity was 2.53 +/- 0.55 mm/sec.

CONCLUSIONS

This study clearly documents the segmental nature of the primate choroidal microvasculature. It also illustrates that choroidal angiography by laser-targeted dye delivery provides information useful for studying the response of the choriocapillaris to physiological and pathologic changes.

Clinicopathological study on carcinoma of the extrahepatic bile duct with special focus on cancer invasion on the surgical margins

To clarify the clinical significance of the status of surgical margins, especially the dissected margin in the transverse direction, a clinicopathologic study was performed on 60 patients with carcinoma of the bile duct who underwent radical resection. The patients in group A (n = 28) had no cancer invasion within 5 mm of the dissected margin in the transverse direction. They had a higher incidence of the well differentiated type of carcinoma and a lower incidence of lymph node metastasis and microscopic tumor extension than the patients in group B. Group B (n = 32) included patients with cancer involvement within 5 mm of the dissected margin in the transverse direction. Some group A patients were found to have advanced carcinoma of the lower bile duct, but they were the only ones whose lesions were at an early stage (e.g., lesion restricted to subserosal involvement or less) among those with carcinoma of the hepatic duct and the upper and middle bile ducts. Local recurrence was found to occur more frequently as the tumor approached the liver, and the incidence of local recurrence was significantly higher in patients in group B than in group A (75.0% versus 28.5%). These results indicate that patients with cancer invasion within 5 mm of the surgical margin develop early recurrence of tumor even after conventional radical resection and that further radical dissection of the hepatoduodenal ligament with hepatectomy or pancreatoduodenectomy may be required to improve survival for these cases.

Centromeric repetitive sequences in Arabidopsis thaliana

Two highly repetitive DNA sequences have been cloned from Arabidopsis thaliana, ecotype Columbia, and were characterized by molecular and cytological analyses. These two sequences belong to the same repeat family with 180-bp basic unit, being tandemly organized in clusters. Pulsed field gel electrophoresis showed that this repeat sequence family forms at least seven clusters from ca. 100 to 1200 kb in length and ca. 3500 kb in total. Fluorescent in situ hybridization to somatic metaphase cells with the monomeric repeat unit as a probe clearly revealed that this repeat family is located at the centromeric regions of all chromosomes. It was also shown that this repetitive sequence is closely associated with limited parts of heterochromatic blocks on the centromeric regions which are visible distinctly at meiotic prophase from leptotene to diakinesis. Furthermore, this sequence hybridized preferentially to both polar sides of five bivalent chromosomes at the first metaphase. These results suggest that the repetitive sequences of this family were derived from the regions very close to the centromeres or on the centromeres themselves.

Evaluation of laser Doppler flowmetry in renal transplantation

Renal grafts are presently evaluated based on the surgeon's observation of the organ microcirculation. Effectiveness of organ microcirculation has traditionally been accomplished through evaluation of the appearance of the graft. Laser doppler flowmetry (LDF) has been suggested as a possible means to determine graft effectiveness. Renal grafts in 46 transplants were studied using LDF and the technique was evaluated. It was found to be a useful technique for monitoring effectiveness of grafts.

[Three-dimensional CT imaging of pulmonary nodules using helical scan CT]

To evaluate the usefulness of three-dimensional (3D) imaging of pulmonary nodules from helical scan CT images, 3D reconstructions were performed in 23 patients, using a CEMAX VIPstation. These cases included 15 lung cancers, six metastatic lung cancers, an aspergilloma and a tuberculoma. The equipment used was a Toshiba CT system, the X force. Helical scan CT data were acquired using up to 20 continuous 1.5 sec rotations with an X-ray beam width of 5 mm and a couchtop movement speed of 5 mm/1.5 sec, and during a single breath-hold. Axial images were reconstructed at a section interval of 2 mm. Helical scan CT permits axial images to be reconstructed at any desired position within the scanned area, and provides images without interslice gaps caused by respiratory movement. Therefore, high-quality 3D images can be obtained from these data. Concerning the optimum threshold range of CT number of 3D reconstruction, we clarified the lower and upper limits (lower/upper), as follows: 1) Solid pulmonary nodule: (-700-(-)400/-100 HU) 2) Tumor invaded to pleura or chest wall: (-700-(-)400/-200 HU) 3) Pulmonary nodule with cavity: (-700-(-)400/50 HU) 4) Small pulmonary nodule (< 10 mm): (-750-(-)600/-100 HU) In all cases, it was possible not only to demonstrate abnormal findings three-dimensionally, but also to grasp anatomical relationships among the pulmonary nodule, bronchi, vessels and chest wall. In conclusion, it was considered that 3D CT imaging provided additional anatomical information and was very useful.

Evaluation of regional cerebral blood flow changes on perifocal brain tissue SPECT before and after removal of arteriovenous malformations

In fifteen cases of arteriovenous malformation (AVM), serial examinations of regional cerebral blood flow (rCBF) using single photon emission computed tomography (SPECT) and N-isopropyl-(123I)p-iodoamphetamine were performed. On SPECT images, the nidus was visualized as a focal rCBF defect in all cases preoperatively and seven of these cases had abnormal decreased perfusion areas in the tissues adjacent to the nidus. In five cases, the postoperative SPECT images on the day after surgery revealed an abnormal increased perfusion area adjacent to the nidus and in one case the increased perfusion was accompanied by a massive intracerebral haemorrhage detected by brain computed tomography (CT). In seven cases, postoperative SPECT images showed widespread abnormal decreased perfusion areas in the surrounding tissues and brain CT revealed either intracerebral haemorrhage or significant cerebral oedema. In the other three cases, no remarkable rCBF changes were found in comparison with the pre-operative study. There was a tendency for the preoperative abnormal decreased perfusion area adjacent to the nidus to correlate with the postoperative hyperperfusion and for the postoperative abnormal decreased perfusion area to reflect brain damage.

[Clinical evaluation of asymmetric film-screen system for thoracic lesions]

We investigated the clinical usefulness of the asymmetric film-screen system on postero-anterior chest roentgenograms for thoracic lesions. The asymmetric film-screen system, the so-called Kodak Insight thoracic imaging system, records a different image on each side of double-emulsion film. An image displaying the lung field is captured on the anterior side of the film, while one displaying the mediastinal, retrocardiac and retrodiaphragmatic structures is captured on the posterior side. The clinical usefulness of the asymmetric film was evaluated in 20 patients for visibility of the anatomical structures and abnormal lesions in comparison with conventional film. In the asymmetric film-screen system, the front and rear screens were HC (high contrast) and Regular, respectively. Chest radiography was performed at 200mA and 100kVp. As conventional film, we used SRC film (Konica, orthotype film), and chest radiography was performed at 100mA and 130kVp. The chest roentgenograms obtained with the asymmetric film-screen system provided better information on normal structures and abnormal lesions in the lung field, but slightly inferior information on mediastinal structures. In conclusion, it was considered that the asymmetric film-screen system was useful for thoracic lesions.

In vitro phagocytosis of polylactide microspheres by retinal pigment epithelial cells and intracellular drug release

We investigated phagocytosis of biodegradable microspheres containing a drug by retinal pigment epithelial (RPE) cells and drug release within the cells to evaluate the potential usefulness of microspheres for intracellular drug delivery. The biodegradable polymers used were L-lactic acid, and DL-lactic acid with different molecular weights or the copolymers of different monomer compositions. The microspheres containing a non-bioactive fluorescent dye (rhodamine 6GX) as a model drug, were prepared by a solvent evaporation method. The in vitro release of the dye from the microspheres was examined. Phagocytosis of the microspheres by RPE cells was conducted to evaluate the extent of phagocytosis by phase-contrast microscopy and transmission electron microscopy. The RPE cells ingesting the microspheres at different stages were examined by fluorescent microscopy to estimate the intracellular release of the dye. The dye was released with time from every microsphere and the release was controlled by changing the type of polymers constituting microspheres. The microspheres containing the dye were phagocytosed by RPE cells and the dye was released intracellularly with time. The present study indicates that the drug incorporated in the microspheres was delivered into RPE cells by way of phagocytosis and released within the cells. It is concluded that this microsphere system is a promising delivery form capable of drug targeting to RPE cells.

A new vitreal drug delivery system using an implantable biodegradable polymeric device

PURPOSE

The authors evaluated the feasibility of using an implantable biodegradable polymeric device to deliver drugs into the vitreous humor.

METHODS

Two types of devices were prepared by compression-molding polymers of poly(DL-lactic acid) of two different molecular weights. The molecular weights of the poly(DL-lactic acid) used were 5,600 (device-1) and 9,100 (device-2). Sodium fluorescein (NaF) served as a hydrophilic drug marker. The release of the dye from the devices was studied in vitro. The intravitreal kinetics of NaF was evaluated in rabbits in vivo by fluorophotometry. The eyes were evaluated electrophysiologically and histologically to determine if there were toxic effects.

RESULTS

Device-1 and device-2 released NaF for more than 25 and 45 days, respectively, in vitro. Detectable concentrations of NaF were present in the vitreous up to 17 days (device-1) and 28 days (device-2). Both types of devices were well tolerated, with no noted toxic effects.

CONCLUSIONS

These results suggested that this device may be a potentially effective system to deliver drugs in the vitreous.

Sensitive colorimetric assay of serum diamine oxidase

A simple and sensitive colorimetric assay for serum diamine oxidase (DAO) activity was based on a coupled reaction with peroxidase and a new chromogen, 10-(carboxymethyl-aminocarbonyl)-3,7-bis(dimethylamino) phenothiazine sodium salt (DA-67). In the presence of peroxidase and DA-67, peroxidase catalyzes the formation of methylene blue having an absorption maximum at 668 nm. The proposed method eliminates the interferences occurring in serum with use of ascorbate oxidase and stops the reaction with sodium diethyldithiocarbamate, leaving the methylene blue in the reaction mixture stable for about 2 h. Low normal basal values of serum DAO can be determined in the range 2.8-9.0 units/l. Since all reagents are commercially available the method is suitable for the clinical laboratory.

Feasibility of drug targeting to the retinal pigment epithelium with biodegradable microspheres

There are several systems of delivering drugs to cells with phagocytic activity. We studied the possibility of targeting drugs to retinal pigment epithelial (RPE) cells with the use of surface-modified microspheres. A fluorescent dye, 1,4-bis[2-(5-phenyloxazolyl)]-benzene (POPOP), was incorporated into microspheres of poly(lactic acid) for use as a marker to evaluate drug delivery. Phagocytosis of the microspheres, with or without gelatin precoating, was carried out at 37 degrees C and 4 degrees C. The cell-incorporated fluorescence of POPOP was measured, and scanning electron microscopy was used to confirm phagocytosis. At 4 degrees C, no uptake of POPOP was noted; however at 37 degrees C, cell-associated fluorescence was observed to increase for up to 24 hr. In comparison with bare microspheres, gelatin precoating significantly enhanced phagocytosis (P < 0.001) at the same incubation times. These results suggested that drug delivery to RPE cells may be feasible by means of surface-modified polymer microspheres.

[Clinical evaluation of 99mTc-MAG3 renal imaging: comparison with 99mTc-DTPA, 99mTc-DMSA and 131I-OIH]

The newly developed 99mTc-labeled renal imaging agent, mercaptoacetyltriglycine (MAG3), is a tubular secreted compound. It is expected the most suitable agent to measure renal function and image urinary tract because of the excellent imaging properties and availability of 99mTc and preferred biological qualities of radiohippurates. We examined 15 patients (8 males, 7 females, mean age 55 years old) with renal and urinary tract disease. After drinking 400 ml of water, 185, 370 or 555 MBq of 99mTc-MAG3 was injected with the supine position. Dynamic scans were acquired for 20 minutes on a large field of view gamma camera (ZLC-7500 Siemens Medical Inc.) linked to a computer system (Scintipac-2400 Shimadzu Co.) in a 64 x 64 matrix. Regions of interest (ROI) were placed around each kidney. Curves of 12 seconds frame rate were generated from all two ROIs over the 20 minutes study. The time to peak count (Tmax) and time from peak count to a half count (T1/2) were calculated from the curve data. 99mTc-DTPA renal imaging was examined to the same patients with the same method like 99mTc-MAG3. The renogram of 131I-orthoiodohippurate (OIH) was performed with probe method. The excellent quality of the renal image was obtained with 185-555 MBq of 99mTc-MAG3 compared with the same dose of 99mTc-DTPA respectively. The diagnostic value of 99mTc-MAG3 renal imaging was as well as 99mTc-DMSA renal imaging. The Tmax of 99mTc-MAG3 renogram was same value of that of both 99mTc-DTPA and 131I-OIH renogram. The T1/2 of 99mTc-MAG3 renogram was significantly lower than that of 99mTc-DTPA renogram. The T1/2 of 99mTc-MAG3 renogram was slightly higher that of 131I-OIH renogram. We conclude that the renal imaging of 99mTc-MAG3 was able to acquire the most excellent image and the proper renogram pattern as same as 131I-OIH renogram.

Kinetic interaction between theophylline and a newly developed anti-allergic drug, pemirolast potassium

The effect of a newly developed anti-allergic drug, pemirolast potassium (TBX), on the pharmacokinetics and metabolism of theophylline was investigated under steady-state conditions in seven healthy male volunteers. A sustained-release theophylline formulation (100 mg twice daily at 12 h intervals) was given as monotherapy and coadministered with TBX (10 mg twice daily at 12 h). Plasma concentration-time curves and the urinary excretion of theophylline and its major metabolites after administration of theophylline alone and after coadministration with TBX were compared. No significant adverse effects from this study were observed. There were no significant differences in the total body clearance, renal clearance and maximum concentration of theophylline between the two treatments, although coadministration of TBX significantly delayed the time to reach maximum concentration of theophylline. In the case of urinary excretion, no significant changes in the fraction of urinary excretion of theophylline and its metabolites were observed. These results indicate that TBX has little or no effect on the pharmacokinetics and metabolism of theophylline and suggest that TBX is safe for asthma patients receiving theophylline therapy for treatment of chronic obstructive airway diseases.

Foveal thickening in retinitis pigmentosa patients with cystoid macular edema

PURPOSE

Clinical evaluation of cystoid macular edema (CME), known to occur in patients with retinitis pigmentosa (RP), is based on the presence of vascular leakage on fluorescein angiography. Due to an inability to quantitatively assess retinal thickening, the degree of thickening from fluid accumulation and its relation to fluorescein dye leakage into the extravascular retinal space has not been established. The relationship between fluorescein dye leakage and foveal thickening and the effect of methazolamide treatment was studied.

METHODS

The retinal thickness analyzer was used to measure the degree of thickening in six patients with RP and CME. A laser beam was projected at an oblique angle to the retina, and images of the intersection of the laser slit with the anterior and posterior retinal surfaces were recorded. The digitized images were analyzed using a dedicated software program to provide quantitative measurements of retinal thickness. Routine fluorescein angiography was performed.

RESULTS

The amount of fluorescein dye leakage was not indicative of the degree of retinal thickening due to fluid accumulation. Foveal thickening and fluorescein dye leakage were reduced in five of six eyes after methazolamide treatment. Eyes with moderate thickening reversed to normal, whereas eyes with severe thickening showed only a minimal reduction in thickness.

CONCLUSION

Retinal thickness measurement is a useful method of evaluating both the extent of and changes in retinal thickness after carbonic anhydrase treatment.

Poly(vinyl alcohol) hydrogels as soft contact lens material

A new type of soft contact lens was developed from the poly(vinyl alcohol) (PVA) hydrogel prepared by a low temperature crystallization technique using a water-dimethyl sulfoxide mixed solvent. The PVA contact lens materials had a water content of 78% and a tensile strength of 50 kg/cm2, five times as strong as that of commercial poly(2-hydroxyethyl methacrylate) soft contact lens. The amount of proteins adsorbed to the PVA soft hydrogel material was half to one thirtieth of that of conventional soft contact lenses. Histological and scanning electron microscopic observation of rabbit eyes which had worn the PVA soft contact lens for 12 weeks showed no difference in corneal epithelium and cell arrangement in the corneal epithelium from the non-wearing eyes.

[A case of anaphylactic shock following the administration of Gd-DTPA]

We experienced a case of serious adverse reaction following the administration of Gd-DTPA (gadolinium with diethylenetriamine pentaacetic acid). The patient showed sneezing and hoarseness when Gd-DTPA was administered for the first time. At the second injection, when hydrocortisone was used in advance to prevent allergic reaction, she lapsed into a pre-shock state and anaphylactic reaction was strongly suggested by the laboratory data. The possibility that Gd-DTPA may cause the severe side effects must be noted.

Metabolism of 5 beta-cholestane-3 alpha,7 alpha-diol in ileectomized rats

The effect of ileectomy on the composition of biliary bile acids and the metabolism of 5 beta-cholestane-3 alpha,7 alpha-diol was studied in rats. In the ileectomized rats, there was an increase in the percentage of cholic acid group (cholic acid and deoxycholic acid) as compared with the normal rats. After rats with a bile fistula were given intravenously 5 beta-[7 beta-3H] cholestane-3 alpha,7 alpha-diol, there was a 3-fold increase in the percentage of [3H]cholic acid in the ileectomized rats compared to the normal rats. The findings have suggested that an increase in the percentage of cholic acid group in the ileectomized rats is due to the increased formation of cholic acid through an alternative pathway which involves 5 beta-cholestane-3 alpha,7 alpha-diol.