Photonic crystal waveguides utilizing a modulated lattice structure

We experimentally demonstrate a new class of optical waveguide consisting of a-Si/SiO(2) autocloned photonic crystals with modulated lattice structure. The waveguide utilizes the macroscopic form birefringence of photonic crystals and confines light by the difference in the effective refractive index. A monopole modal field with spot diameters of 6.9 micromx6.5 microm was observed at a wavelength of 1.55 microm. The propagation loss of the waveguide at the wavelength was found to be ~4.2 dB/mm at most.

Differential regulation of porcine hepatic IGF-I mRNA expression and plasma IGF-I concentration by a low lysine diet

The influence of dietary lysine on hepatic insulin-like growth factor-I (IGF-I) gene expression and plasma IGF-I level was investigated. Two male 6-wk-old pigs from each of six litters were used. Each littermate was assigned to one of two diets, control or low lysine (LL), that were isoenergetic and similar in protein content and provided 14.3 MJ digestible energy/kg for both diets, 185 g protein/kg for the control diet and 180 g protein/kg for the LL diet. The control diet contained all essential amino acids in the recommended amounts, including 11.5 g lysine/kg. The LL diet was similar but contained only 7 g lysine/kg. Pigs were pair-fed these diets for 3 wk. Growth rates and feed efficiencies of pigs fed the LL diet were significantly lower than those of pigs fed the control diet (P < 0.01). Plasma IGF-I levels in pigs fed the LL diet were 52% lower than in those fed the control diet (P < 0.01), and the LL group also had lower plasma IGF-binding protein-3 (IGFBP3) levels (P < 0.05). Despite the strikingly lower plasma IGF-I in pigs fed the LL diet, hepatic IGF-I mRNA abundance did not differ between the two treatment groups. We conclude that the reduction in plasma IGF-I caused by reduced dietary lysine may have been due in part to suppression of post-transcriptional events in IGF-I expression. The lower plasma IGFBP3 in pigs fed the LL diet suggests that increased clearance rates of circulating IGF-I may have been involved in this response.

Ocular absorption behavior of palmitoyl tilisolol, an amphiphilic prodrug of tilisolol, for ocular drug delivery

The objective of this study was to examine the ocular absorption behavior of an amphiphilic prodrug after instillation onto the cornea of rabbits. A micellar solution of O-palmitoyl tilisolol (PalTL), an amphiphilic prodrug, was prepared. After instillation of tilisolol (TL) and PalTL, the drug concentrations in the tear fluid, cornea, aqueous humor, iris-ciliary body, vitreous body, and blood were measured. In addition, in situ ocular absorption behavior was also evaluated. After instillation of TL, the concentration of TL in the tear fluid quickly decreased. After instillation of PalTL, prolonged retention and high concentrations of PalTL in tear fluid and the cornea were observed. In addition, more prolonged retention of the TL concentration after instillation of PalTL than after instillation of TL was observed in the cornea, aqueous humor, and iris-ciliary body. In situ experiments demonstrated that PalTL was mainly absorbed by the corneal route and the improvement effects of PalTL under in vivo conditions was due to an enhanced transit time of PalTL in ocular tissues. PalTL, an amphiphilic prodrug, exhibited increased retention in the precorneal area compared with the parent drug, TL, resulted in improved ocular absorption of the parent drug.

Serum progesterone and estradiol-17beta concentrations, and lapaloscopic observations of the ovary in the cheetah (Acinonyxjubatus) with pregnant mare serum gonadotropin and human chorionic gonadotropin treatments

In 3 adult female cheetahs, induced-superovulation treatment was conducted, by means of 200 IU of pregnant mare serum gonadotropin (PMSG) and 100 IU of human chorionic gonadotropin (hCG) 80 hr after PMSG. The administration of PMSG created a sharp increase in the estradiol-17beta concentration, resulting in 232 pg/ml 8 hr later in one specimen out of three. The hCG administration showed an increase in the progesterone concentration of 2.29 ng/ml 46 hr later. In addition, after direct observation of the ovary surface by laparoscopy, 5 follicles in the right ovary over 2 mm in diameter, and 7 corpora lutea (5 in the right ovary and 2 in the left) were found. It is assumed that ovulation can be induced with hCG after 80 hr on PMSG during a cheetah's diestrus or proestrus.

[Efficacy of a single-day administration of levofloxacin for the prevention of urinary tract infections after urogenital examinations and treatments for outpatients]

The clinical efficacy of a single-day oral administration of levofloxacin (LVFX) for the prevention of urinary tract infections (UTI) after urogenital examinations and treatments for outpatients was assessed. A single-day oral administration of LVFX, 100 mg three times a day, was compared to a single dose intra-muscular injection of 100 mg netilmicin sulfate or 100 mg dibekacin sulfate. Three of 219 cases (1.4%) and 7 of 304 cases (2.3%) contracted UTI in the single-day oral administration group and the single dose intra-muscular injection group, respectively. Adverse reactions were observed in 3 of 219 cases (1.4%) and 27 of 304 cases (8.8%) in the single-day oral administration group and the single dose intra-muscular injection group, respectively. In the single dose intra-muscular injection group, UTI and adverse reactions were more severe than in the single-day oral administration group. Therefore, a single-day oral administration of LVFX was superior to a single dose intra-muscular injection of netilmicin sulfate or dibekacin sulfate in the prevention of UTI with less probability of the adverse effects. A single-day oral administration of LVFX was concluded to be sufficient for the prevention of UTI caused by examinations and treatments for outpatients.

Controlled release and ocular absorption of tilisolol utilizing ophthalmic insert-incorporated lipophilic prodrugs

To control ocular drug delivery, the O-butyryl ester prodrug of tilisolol (BUTL) and the O-palmitoyl ester prodrug of tilisolol (PalTL) were incorporated into an ophthalmic insert. The released TL from BUTL inserts and PalTL inserts in pH 7.4 phosphate-buffered saline until 5 h were approximately 25% and 3% of that from TL inserts, respectively. In addition, BUTL was also released from BUTL inserts. However, PalTL was not released from the PalTL insert. The release of drugs from TL inserts and BUTL inserts was little affected by the addition of bovine serum albumin (BSA) in pH 7.4 phosphate-buffered saline. In contrast, the release of drugs from PalTL inserts were enhanced by the addition of BSA. After application of TL, BUTL, and PalTL inserts to the rabbit eye, the aqueous humor concentration of TL was prolonged compared with TL instillation, and the plasma concentration of TL was much lower than that of TL instillation. The ratios of the area under the TL concentration-time curve (AUC) in the aqueous humor to AUC in the plasma (AUC(aqueous)/AUC(plasma)) after application of BUTL until 8 h were 3.1-fold and 3.8-fold higher than those of the TL insert and PalTL insert, respectively.

Effect of instillation method on the absorption of phenolsulphonphthalein as a model drug from the liver and small intestinal serosal surface in rats

We have examined the effect of the instillation method on the absorption of a drug from the liver and the small intestinal serosal surface in rats. We performed continuous microinstillation via an infusion pump and bolus instillation via a syringe, using phenolsulphonphthalein (phenol red) as the model drug. After continuous microinstillation of phenolsulphonphthalein 2.35 mg in 235 microL for 5 min on the liver and small intestinal serosal surface in rats, the AUC (area under the curve) of the plasma concentration profile up to 60 min was significantly higher compared with bolus instillation. A similar trend was observed after continuous microinstillation of phenolsulphonphthalein 2.35 mg in 117.5 microL for 2.5 min. The calculated absorption rate constants (Ka) after continuous microinstillation of phenolsulphonphthalein based on a two-compartment model with first-order absorption were higher than those after bolus instillation on the liver and small intestinal serosal surface at either instillation concentration. Moreover, Ka was increased after continuous microinstillation of 2.35 mg in 117.5 microL at either instillation site. Instillation of phenolsulphonphthalein on the liver surface resulted in a 1.2- to 2.3-fold higher Ka compared with the small intestinal serosal surface. This tendency was marked after continuous microinstillation of 2.35 mg in 117.5 microL. In conclusion, absorption could be enhanced by instilling a small amount of drug solution on the liver surface gradually and continuously, suggesting a promising approach for instillation site-selective drug delivery in the peritoneal cavity.

Tracheal invasion by thyroid carcinoma: prediction using MR imaging

OBJECTIVE

The purpose of this study was to evaluate the accuracy of MR imaging in predicting tracheal invasion by thyroid carcinomas and to determine MR imaging criteria for diagnosing tracheal invasion.

MATERIALS AND METHODS

MR imaging was performed on the normal trachea of one cadaver and 30 healthy subjects as a standard of reference. Then, MR imaging findings in 67 patients with thyroid carcinoma were reviewed and correlated with surgical and pathologic findings. A logistic regression model was used to determine which MR imaging features were significant for predicting tracheal invasion.

RESULTS

Twenty-three (34%) of the 67 patients had tracheal invasion. Logistic regression model analysis revealed that significant MR characteristics for determining tracheal invasion included soft-tissue signal in the tracheal cartilage (p < 0.001), intraluminal mass (p < 0.001), and degree of tumor circumference around the trachea (p = 0.001). The highest accuracy (90%) for determining tracheal invasion was achieved using a combination of findings. A case was considered positive for tracheal invasion if there was soft-tissue signal in the cartilage, an intraluminal mass, or a tumor that abutted a circumference of the trachea of 180 degrees or greater. Using these factors resulted in seven false-positive diagnoses because soft-tissue signal in the cartilage was sometimes seen in healthy trachea. Although intraluminal mass invariably reflected deep tracheal invasion, soft-tissue signal in the cartilage rarely indicated actual cartilage invasion but rather indicated tumor extension between the cartilaginous rings.

CONCLUSION

Tracheal invasion by thyroid carcinomas can be accurately diagnosed with MR imaging, and using a combination of criteria is the most accurate method of predicting this phenomenon.

SPARC expression in primary human renal cell carcinoma: upregulation of SPARC in sarcomatoid renal carcinoma

SPARC (secreted protein acidic and rich in cysteine, also called osteonectin, BM-40, and 43K protein) is a matricellular protein and is associated with cell-matrix interactions during cell proliferation and extracellular remodeling. It is also implicated in the neovascularization, invasion, and metastasis of human malignancies. To investigate a potential role of the SPARC in renal tumorigenesis, we examined primary renal cell carcinomas (RCCs) for SPARC expression by Northern blot analysis and for protein distribution by immunohistochemistry. We found that 6 (100%) of 6 sarcomatoid and 25 (70%) of 36 clear-cell carcinomas had enhanced SPARC transcription compared with that of the corresponding normal kidney tissue. In contrast, papillary and chromophobe RCCs characterized by a hypovascular or avascular tumor phenotype had undetectable SPARC expression. Immunohistochemical analysis showed that SPARC was strongly stained in the cytoplasm of the sarcomatoid neoplastic cells in sarcomatoid RCCs, whereas it was expressed only in the vascular endothelial cells and fibroblasts in clear-cell RCCs. SPARC staining intensity in the stromal cells was increased in the invading portion in some clear-cell RCCs. These findings suggest that tumor development, including neovascularization and invasion in clear-cell RCCs, might be regulated by SPARC from stromal endothelial cells and fibroblasts and that sarcomatoid transformation from common-type RCCs is associated with upregulation of SPARC expression; SPARC may contribute to its aggressive tumor phenotype.

Lingual calcinosis circumscripta in a captive sitatunga

Calcinosis circumscripta (CC) was found in a 10-yr-old female sitatunga (Bovidae; Tragelaphus spekei). At necropsy, there were two white coalescing nodules (3 x 5 x 2 cm, 2 x 2 x 1.5 cm) on the ventral side of the tongue. The cut surface of the nodules had multiple, well-circumscribed loculi with chalky appearance and gritty consistency, separated by thin strands of connective tissue. Histologically, the nodules contained multiple loculi of various sizes and shapes, which consisted of amorphous material that was pale basophilic with H&E stain, surrounded by fibrous connective tissue. Around the loculi were numerous foreign body giant cells and epithelioid macrophages; occasional lymphocyte aggregations also were seen. The amorphous material was positive for PAS and von Kossa's stain. Calcinosis circumscripta is rare in the Bovidae.

Malignant melanoma of the palpebral conjunctiva in a captive fallow deer

A case of malignant melanoma in the conjunctiva of the eyelid of a captive 13-yr-old female fallow deer (Dama dama) was studied. The black tumor that protruded to the palpebral conjunctiva of the right lower eyelid consisted of an infiltrative growth of melanin-containing neoplastic cells with marked cytological atypia. The tumor involved the conjunctiva of the right lower eyelid and infiltrated to the conjunctival epithelial layer, but did not reach the palpebral skin. Numerous mitotic figures and lymphatic invasions were observed. This is a very rare case of a malignant melanoma arising from the palpebral conjunctiva in a wild ruminant.

Successful treatment of metastatic adenocarcinoma of the urachus: report of 2 cases with more than 10-year survival

Metastatic urachal cancer is often considered lethal. We report 2 cases of metastatic urachal carcinoma successfully treated with surgical excision followed by combinations of surgery, radiation, and chemotherapy against local recurrence and/or distant metastases, with a recurrence-free survival period of more than 10 years. These cases provide support for multimodal treatments of metastatic urachal cancer.

Head and neck lesions: characterization with diffusion-weighted echo-planar MR imaging

PURPOSE

To evaluate whether apparent diffusion coefficients (ADCs) calculated from diffusion-weighted echo-planar magnetic resonance (MR) images can be used to characterize head and neck lesions.

MATERIALS AND METHODS

Diffusion-weighted echo-planar MR imaging was performed with a 1.5-T MR unit in 97 head and neck lesions in 97 patients. Images were obtained with a diffusion-weighted factor, factor b, of 0, 500, and 1,000 sec/mm(2), and an ADC map was constructed. The ADCs of lesions, cerebrospinal fluid, and spinal cord were calculated.

RESULTS

Acceptable images for ADC measurement were obtained in 81 (84%) patients. The mean ADC of malignant lymphomas, (0.66 +/- 0.17[SD]) x 10(-3) mm(2)/sec (n = 13), was significantly smaller (P <.001) than that of carcinomas. The mean ADC of carcinomas, (1.13 +/- 0.43) x 10(-3) mm(2)/sec (n = 36), was significantly smaller (P =.002) than that of benign solid tumors. The mean ADC of benign solid tumors, (1.56 +/- 0.51) x 10(-3) mm(2)/sec (n = 22), was significantly smaller (P =.035) than that of benign cystic lesions, (2.05 +/- 0.62) x 10(-3) mm(2)/sec (n = 10). No significant differences were seen in the mean ADC of cerebrospinal fluid and of spinal cord among four groups of lesions. When an ADC smaller than 1.22 x 10(-3) mm(2)/sec was used for predicting malignancy, the highest accuracy of 86%, with 84% sensitivity and 91% specificity, was obtained.

CONCLUSION

Measurement of ADCs may be used to characterize head and neck lesions.

Sustained ocular delivery of tilisolol to rabbits after topical administration or intravitreal injection of lipophilic prodrug incorporated in liposomes

To improve the retention time of tilisolol in the precorneal area or vitreous body, we prepared liposomes incorporating the O-palmitoyl prodrug of tilisolol. O-Palmitoyl tilisolol was completely incorporated in the liposomes. After topical administration of O-palmitoyl tilisolol liposomes to the rabbit eye, O-palmitoyl tilisolol rapidly disappeared from the tear fluid. The inclusion of 2% carmellose sodium slightly prolonged the retention of O-palmitoyl tilisolol in the tear fluid. After intravitreal injection of O-palmitoyl tilisolol liposomes, there was a relatively prolonged retention of O-palmitoyl tilisolol in the vitreous body. At 24 and 48 h after intravitreal injection of O-palmitoyl tilisolol liposomes, the tilisolol concentration in the vitreous body was significantly higher compared with the concentration after intravitreal injection of tilisolol liposomes.

Physician's attitudes towards disclosure of cancer diagnosis to elderly patients: a report from Tokyo, Japan

Physicians' attitudes towards the disclosure of a cancer diagnosis to 114 consecutive patients (age range, 65-93 years; median 78 years) admitted to the Tokyo Metropolitan Tama Geriatric Hospital from April 1994 to May 1995 were analyzed utilizing a questionnaire administered to the attending physicians. Eighty-seven patients (76%) had been informed of their diagnosis before the initiation of cancer treatment, while 27 patients (24%) were not told. 'To carry out the treatment under patient's understanding' and 'consideration for patient's quality of life' were the major reasons for diagnosis disclosure, while 'lack of patient's ability to understand the information' and 'family's wish that the patient not be informed of the truth' were the major reasons for non-disclosure. Dementia, deteriorated performance status, and non-curability were major factors related to non-disclosure. Even with decisional ability, 15% of patients were not told their cancer diagnosis because wishes of their families were preferred. The current results suggest that telling cancer diagnosis to the elderly patients will not yield negative attitude of the patients and that there is no rationale for physicians to hesitate to disclose cancer diagnosis merely because of patient's high age.

Suppression of spermatogenesis in ipsilateral and contralateral testicular tissues in patients with seminoma by human chorionic gonadotropin beta subunit

OBJECTIVES

The pathologic complexity of the testicular tumor makes it difficult to demonstrate exactly the relationship between the impaired spermatogenesis in patients with a testicular tumor and the serum level of the human chorionic gonadotropin beta subunit (beta-hCG). Therefore, we performed quantitative evaluation of spermatogenesis in ipsilateral and contralateral testicular tissues of seminoma to simplify the relation pathologically and endocrinologically and to demonstrate the exact correlation between spermatogenesis and serum beta-hCG levels.

METHODS

Fifty-three biopsy specimens from ipsilateral and contralateral testicular tissues of seminoma were analyzed histologically. The quantitative evaluation of spermatogenesis was performed by the mean Johnsen's score count (MJSC). Beta-hCG expression in seminoma was examined immunohistochemically. Serum beta-hCG, testosterone, estradiol, luteinizing hormone, and follicle-stimulating hormone levels were analyzed before orchiectomy.

RESULTS

A significant linear relationship (r = -0.82; P <0.005) was found between the serum level of beta-hCG and the MJSC in contralateral testicular tissues but not in ipsilateral ones, although the suppression of spermatogenesis was observed in both sides without suppression of luteinizing hormone and/or follicle-stimulating hormone production.

CONCLUSIONS

A clearcut fall in the MJSC with an associated rise in the serum level of beta-hCG was demonstrated in the contralateral testicular tissues but not in the ipsilateral ones of seminoma. It seems most likely that serum beta-hCG suppresses spermatogenesis in both ipsilateral and contralateral testicular tissues without the suppression occurring through the hypothalamus-pituitary-gonadal system, and also that some less well recognized factors affect spermatogenesis, making the relation between serum beta-hCG and MJSC obscure in ipsilateral testicular tissues.