MR imaging of congenital or developmental neuropathic strabismus: common and uncommon findings

BACKGROUND AND PURPOSE

High-resolution MR imaging enables direct imaging of the ocular motor nerves. The aim of this study was to assess the various causes of congenital or developmental neuropathic strabismus by using high-resolution MR imaging.

MATERIALS AND METHODS

High-resolution MR imaging was performed to evaluate the ocular motor nerves (CNIII, CNIV, CNVI) in 247 consecutive patients with suspected congenital or developmental neuropathic strabismus. These MR images, along with those obtained from conventional MR imaging of the brain and the orbit, were evaluated.

RESULTS

MR imaging abnormalities were found in 112 patients: ocular motor nerve abnormalities in 98 patients (88%), orbital abnormalities in 9 patients (8%), and brain abnormalities in 5 patients (4%). Ocular motor nerve abnormalities were CNIV aplasia (63%), CNVI aplasia or hypoplasia (21%), CNIII aplasia or hypoplasia (3%), and combined CNIII aplasia and CNVI hypoplasia (1%). Orbital abnormalities were EOM hypoplasia (7%), EOM hypertrophy (1%), and fibrotic mass (1%). Brain abnormalities were periventricular leukomalacia (4%) and periventricular heterotopia (1%).

CONCLUSIONS

Various MR imaging abnormalities were associated with congenital and developmental neuropathic strabismus. The most common abnormality was CNIV aplasia.

Measurement of ocular torsion using iterative optical flow

This work represents a new method for measuring ocular torsion using optical flow. Feature points are obtained from reference and current image, and the relative optical flows of each point are calculated. The feature points are selected according to the strength of corner on the signature of iris. This method is robust and effective in calculation.

Treatment of HIV positive anal cancer patients with chemoradiation

4154

Background: Tolerance and outcomes of HIV+ anal cancer patients are questioned, especially since the emergence of High Active Anti-Retroviral Therapy (HAART) in the mid-1990s. Our experience in treating these patients before and during the HAART era is reported. Methods: From 1987–2003, 19 HIV+ invasive anal cancer patients were treated with: 30–60 Gy pelvic RT (2 Gy/d) + Mitomycin C (10 mg/m2 bolus on d1) + 5-FU (1000 mg/m2/d, continuous infusion d1–4 and 28–31). Results: Mean CD-4 count at cancer diagnosis was 311, with 9 on HAART. Mean CD-4 count for HAART was 383 and 247 for non-HAART. Stage distribution: 1 T1, 9 T2, 9 T3, 18 N0, 1 N3. Mean f/u was 40 months. 79% had complete response after chemoRT. 4 had locally persistent disease. There was 1 loco-regional recurrence and 2 distant metastases. 79% of the cohort is colostomy-free. Median OS has not been reached. OS at 2 and 3 years were: 88%and 79%, with 10 Alive and NED, 1 Alive with disease, 3 Dead of disease, 5 Dead from intercurrent disease (all secondary to AIDS). 1.5 year DFS was 74%. Break and CD-4 count < 200 had a statistically significant negative impact on DFS, but not OS. HAART did not affect either factor. 11 had RT break for median of 17 days. There was no Grade 4 skin toxicity. All completed the 2nd 5-FU cycle: 7 had delay (median 7 days) and 3 had dose decrease. There were 6 hospitalizations: 5 neutropenic fevers and 1 perineal abscess rupture. WBC Toxicity: 6-Grade 3 and 2-Grade 4. Platelet Toxicity: 2-Grade 3. Heme toxicity was not affected by HAART or CD4 count < 200. There were no treatment related deaths. Conclusion: HIV+ anal cancer patients have reasonable tolerance and outcomes with chemoRT. CD-4 count < 200 and break were negative prognostic factors for DFS. Our 79% colostomy free survival is similar to RTOG 9208, where suboptimal control was attributed to mandatory RT break. Factors influencing break include heme and skin toxicity. To improve the therapeutic ratio, substitution of Mitomycin-C with Cisplatin, IMRT, and Ethyol are being explored.

No significant financial relationships to disclose.

Leber's hereditary optic neuropathy mutations in Korean patients with multiple sclerosis

Several different mitochondrial DNA (mtDNA) sites for mutations of Leber's hereditary optic neuropathy (LHON) have been reported to be present in patients with multiple sclerosis (MS). To further study this association of LHON and MS in the Korean population, we tested 20 MS patients for the presence of mtDNA mutations at nucleotide (nt) 11778 in all 20 patients, and at nt 14484, nt 3460 and nt 15257 in 15, 12 and 12 patients, respectively. However, none of the MS patients exhibited any pathogenic LHON mtDNA mutations. In conclusion, we found no evidence for any association between MS and the LHON mutation in the Korean population.

Adult lymphoblastic lymphoma in Taiwan: an analysis of treatment results of 26 patients

Lymphoblastic lymphoma (LBL) frequently affects young adults and usually presents with a mediastinal mass as well as bone marrow involvement. Although the frequency of LBL in the Far East is higher than that of Western countries, no reports regarding treatment of this disease have as yet been reported. We herein report our treatment experience and verify the efficacy of the Stanford/Northern California Oncology Group (NCOG) protocol for this disease and recommend treatment strategies for LBL patients. We retrospectively reviewed the medical records of adult LBL patients treated in our hospital from 1986 to 1996. Twenty-seven patients were diagnosed to have LBL. These patients' ages ranged from 17 to 73 years old with a median of 23. Nineteen patients had an initial stage IV disease. Of the 23 cases in which immunological studies were performed, 20 proved to be of T cell lineage, 1 of B cell type, and the other 2 lacked both T and B markers. Three major chemotherapeutic regimens including prednisone, methotrexate, doxorubicin, cyclophosphamide, etoposide-mechlorethamine, vincristine, procarbazine, prednisone (ProMACE-MOPP), cyclophosphamide, hydroxydaunomycin, vincristine, prednisone (CHOP), and the Stanford/NCOG protocol were used to treat 3, 6, and 15 patients, respectively. Two other patients were treated with two different chemotherapeutic regimens, respectively. One patient was excluded for analysis because of initial treatment by surgery. The complete response (CR) rates with ProMACE-MOPP, CHOP, and the Stanford/NCOG regimens were 0%, 17%, 80% and median overall survival 9, 8.5, and 15 months, respectively. Five patients with stage II-III diseases achieved long-term disease-free survival of 11-36 months with the Stanford/NCOG protocol with a median follow-up of 24 months. Four patients in late stage or relapse received allogeneic bone marrow transplantation (BMT). Two of them obtained long-term disease-free survival. Two other patients in CR were treated with high-dose chemotherapy (HDCT) supported with autologous BMT and peripheral blood stem cell transplantation (PBSCT), respectively. The patient receiving HDCT with autologous PBSCT died of LBL relapse 6 months after transplantation. The other patient undergoing HDCT with autologous BMT died of fulminant hepatitis 5.5 months after transplantation. The median overall survival of all these 26 patients was 12 months. B symptoms and treatment without the Stanford/NCOG protocol were found to have significantly negative impacts on both patients' overall and progression-free survivals. Our results suggest that the Stanford/NCOG protocol may be an effective chemotherapy for adult LBL and may provide long-term remission for patients in an early stage of disease. For those patients with LBL in an advanced stage or in relapse, HDCT with allogeneic or autologous BMT is probably the treatment of choice.

Stromelysin gene transfer into cultured human trabecular cells and rat trabecular meshwork in vivo

PURPOSE

To determine whether stromelysin gene can be introduced into and expressed in the cultured human trabecular cells as well as in the rat eye in vivo through means of a recombinant replication-deficient adenovirus.

METHODS

Stromelysin cDNA was obtained by reverse transcription-polymerase chain reaction with mRNA extracted from the cultured human trabecular cells after induction with interleukin 1alpha. Adenovirus vector that contains stromelysin cDNA was constructed by cotransfection of pJM17 and pDeltaA.CMV-str into the 293 cells. The expression of stromelysin in the cultured human trabecular cells was assayed by Western blot and zymography. The expression of stromelysin in the trabecular meshwork of the rat eyes was detected by in situ hybridization and immunohistochemistry.

RESULTS

The constructed adenovirus vector contained stromelysin cDNA, but no E1 region. Western blot and zymogram revealed that the stromelysin could be expressed and that it possessed enzymatic activity in cultured human trabecular cells. In situ hybridization and immunostaining of the stromelysin showed that the complete form of stromelysin was expressed in the trabecular meshwork, the iris, and the uveoscleral outflow pathway of the rat eye.

CONCLUSIONS

Stromelysin, a functional gene, can be transferred in vivo into rat eyes and in vitro into cultured human trabecular cells using a replication-deficient adenovirus vector. This shows the possibility of gene therapy in glaucoma.

Studies on anthracenes. 2. Synthesis and cytotoxic evaluation of 9-acyloxy 1,8-dichloroanthracene derivatives

The synthesis and cytotoxic evaluation of 9-acyloxy 1,8-dichloroanthracene derivatives are described. The system selectively reduces the carbonyl group flanked by the peri substituents of the anthracenediones to give the corresponding 1,8-dichloro-9(10H)-anthracenone. Simple acylation of anthracenone occurred with appropriate acyl chlorides in CH2Cl2 with a catalytic amount of pyridine to give the 9-acyloxy-1,8-dichloroanthracene derivatives. Considerable interest has developed in the mechanism of how anthracenones achieve this desirable selectivity. These compounds were evaluated in vitro for their ability to inhibit the growth of human oral epidermoid carcinoma cells (KB cell line), human cervical carcinoma cells of ME 180 (GBM 8401) and Chinese hamster ovary (CHO) cells, respectively, as compared to mitoxantrone. The in vitro cytotoxicity evaluation of 9-acyloxy 1,8-dichloroanthracenes against these above cell lines revealed for most of the compounds a cytotoxic potency lower than that of mitoxantrone. The most active compounds were thus selected for further in vitro biological evaluation and structural modification.

Different risks of symptomatic brain necrosis in NPC patients treated with different altered fractionated radiotherapy techniques

PURPOSE

To report our observation of excessive temporal lobe necrosis in nasopharyngeal carcinoma (NPC) patients treated with 160 cGy b.i.d. radiotherapy technique. During the same period, patients treated with 120 cGy b.i.d. have not shown a similar tendency. Our experience may be useful for designing unconventional radiotherapy regimens for NPC patients.

METHODS AND MATERIALS

During the period from October 1991 to January 1998, 81 M0, previously untreated NPC patients completed altered fractionated radiotherapy. Seventy patients were treated with the hyperfractionated technique, and 11 were treated using the accelerated-hyperfractionated scheme. Hyperfractionated radiotherapy was delivered using 120 cGy b.i.d. separated by 6-h intervals throughout the course. A minimum tumor dose of 8000 cGy was the standard dose over an 8-week period. With the accelerated-hyperfractionated scheme, 160 cGy was given twice daily, also with an interval of 6 h. The minimum tumor dose ranged between 6840 and 7640 cGy, with 7 of the 11 patients receiving 7000 cGy. The arrangement of portals was the same for both regimens. The follow-up period for patients alive was from 32 to 102 months with a median of 61 months for the hyperfractionated patients. For the accelerated-hyperfractionated group, it ranged from 67 to 82 months with a median of 72 months. No patient was lost to follow-up.

RESULTS

At the time of analysis, 49 of the 70 patients in the hyperfractionated group were alive. In the accelerated group, 8 of the 11 patients were alive. The estimated radiation dose to the temporal lobe for the hyperfractionated group was 6000-7440 cGy with a median of 7080 cGy. For the accelerated-hyperfractionated group, the dose range was 4480-6700 cGy with a median of 6400 cGy. Of the 70 patients treated with hyperfractionated radiotherapy, none developed symptomatic brain necrosis, despite the higher total dose to the temporal lobe in general. In contrast, 3 of the 11 (27%) patients irradiated using the accelerated-hyperfractionated regimen suffered from temporal lobe necrosis at 16, 19, and 40 months after completion of radiotherapy.

CONCLUSION

An excessive incidence of temporal lobe necrosis was noted when an accelerated-hyperfractionated regimen with 160 cGy b.i.d. was used in NPC patients with a median brain dose of 6400 cGy. There has been no such event in patients treated using a hyperfractionated regimen with 120 cGy and a median brain dose of 7000 cGy. The real causes of this discrepancy are not known. However, a high sensitivity of the human brain to a change in fraction size may play a role.

Studies on anthracenes. 3. Synthesis, lipid peroxidation and cytotoxic evaluation of 10-substituted 1,5-dichloro-9(10H)-anthracenone derivatives

The synthesis of a series of 1,5-dichloro-9(10H)-anthracenones bearing O-linked and N-linked substituents in the 10-position are described. Previous studies have shown that 9-acyloxy 1,5-dichloroanthracenes and 9-acyloxy 1,8-dichloroanthracenes displayed a potential cytotoxic effect. These results have encouraged us in further investigation of potential anthracenone derivatives. Therefore, a series of 10-substituted 1,8-dichloro-9(10H)-anthracenone derivatives were synthesized. These compounds were evaluated for their ability to inhibit the growth of human oral epidermoid carcinoma cells (KB cell line), human cervical carcinoma cells of ME 180 (GBM 8401) and Chinese hamster ovary (CHO) cells, respectively. Compounds 3c and 4c of this series compare favorably in the KB cellular assay with mitoxantrone. Compound 4c showed combined inhibitory action against KB, GBM and CHO cell growth, respectively. In addition, redox property of the compounds for the inhibition of lipid peroxidation in model membranes was determined. Compounds 4b and 4d exhibited stronger antioxidant activity than ascorbic acid, (+)-alpha-tocopherol and mitoxantrone, respectively.

Comparison between anisometropic and strabismic amblyopia using functional magnetic resonance imaging

AIMS

To assess calcarine activation with functional magnetic resonance imaging (fMRI) in patients with anisometropic and strabismic amblyopia.

METHODS

14 amblyopes (eight anisometropic and six strabismic) were studied with fMRI using stimuli of checkerboards of various checker sizes and temporal frequencies. While T2* weighted MRI were obtained every 3 seconds for 6 minutes, patients viewed the stimuli monocularly with either the amblyopic or sound eye.

RESULTS

Amblyopic eyes showed reduced calcarine activation compared with contralateral sound eyes in fMRI in all subjects. The calcarine activation from amblyopic eyes in anisometropic amblyopes was more suppressed at higher spatial frequencies, while that from amblyopic eyes in strabismic amblyopes was more suppressed at lower spatial frequencies.

CONCLUSION

These results suggest that fMRI is a useful tool for the study of amblyopia in humans. The calcarine activation via amblyopic eyes because of anisometropia or strabismus has different temporospatial characteristics, which suggests differences in the neurophysiological mechanisms between two types of amblyopia.

Studies on anthracenes. 1. Human telomerase inhibition and lipid peroxidation of 9-acyloxy 1,5-dichloroanthracene derivatives

The synthetically useful approaches to 9-acyloxy 1,5-dichloroanthracene derivatives are reported. The system selectively reduces the carbonyl group flanked by the peri substituents of the anthracenediones to give the corresponding 1,5-dichloro-9(10H)-anthracenone. Simple regioselective acylation of anthracenone is applied with appropriate acyl chlorides in CH2Cl2 with catalytic amount of pyridine to give the novel 9-acyloxy 1,5-dichloroanthracene derivatives. Considerable interest has developed in the mechanism of how anthracenone achieves this desirable selectivity. In an attempt to understand the mechanism of this reaction, solid-state structures of anthracene derivatives have been obtained. In addition, the inhibition of lipid peroxidation in model membranes was determined as was their ability to inhibit the telomere-addition function of the human telomerase enzyme together with their inhibition of the Taq polymerase enzyme. In contrast to (+)-alpha-tocopherol, 3b, 3c, 3d, 3g, and 3i do not enhance lipid peroxidation in model membranes. Implications for 9-acyloxy 1,5-dichloroanthracene analogues as potential anticancer agents are discussed.

Binocularity and spatial frequency dependence of calcarine activation in two types of amblyopia

OBJECTIVE AND BACKGROUND

Strabismus and anisometropia early in life frequently causes monocular amblyopia. Activation of the visual cortex is compared between the two types of amblyopia to elucidate differences in the pathogenetic mechanism of the disease.

METHODS

Using an EPI gradient echo sequence in 1.5T MRI, calcarine activation by monocular viewing of checkerboard patterns with reversal was examined in terms of binocularity of the activation and dependence on the spatial frequency of the stimuli.

RESULTS

First, the proportion of voxels activated by both normal and amblyopic eye monocular stimulations is lower in the strabismic group than in the anisometropic group. Second, the activation by higher-spatial-frequency stimuli is reduced in the anisometropic group, but not in the strabismic group.

CONCLUSIONS

These findings from the human visual cortex are consistent with the view proposed based on animal research that the loss of binocular interaction and the undersampling of high-spatial-frequency components of visual stimuli are each one of the underlying changes in strabismic and anisometropic amblyopia, respectively.

A randomized comparison of prism adaptation and augmented surgery in the surgical management of esotropia associated with hypermetropia: one-year surgical outcomes

OBJECTIVE

To compare motor and sensory 1-year surgical outcomes in patients with hypermetropic esotropia, managed with either augmented surgery based on the average of the near deviation with and without correction or preoperative prism adaptation.

METHODS

Forty-three patients with hypermetropic esotropia without distance-near disparity entered a randomized prospective evaluation of augmented surgery (group A, 27 patients) versus prism adaptation (group P, 16 patients). The formula for augmenting the amount of the rectus muscle recession was based on the average of the near deviation with and without correction in group A and the prism-adapted angle of deviation in group P. During prism adaptation, 9 of 16 patients in group P responded to prism. Motor and sensory outcomes of the Worth 4-dot test at 6 and 0.33 m and the Titmus stereotest were evaluated 1, 3, 6, and 12 months after surgery.

RESULTS

Postoperative deviations of 8 PD or less at distance were achieved in 24 of 27 patients (89%) of group A and in 7 of the remaining 8 patients (88%) of prism responders and in all 7 prism nonresponders (100%) in group P. No significant difference existed between groups A and P, as well as between the prism responders and prism nonresponders in group P in terms of near and distance deviation 1 year after surgery. The sensory outcomes improved over time in group A and prism responders.

CONCLUSION

There were no significant differences in the surgical outcomes between each group. However, the small sample size may limit the power to detect any statistically significant differences.

Spontaneous resolution of infantile esotropia

PURPOSE

To report the spontaneous resolution of infantile esotropia in 3 patients.

METHODS

The clinical histories and the results of ophthalmologic examinations in 3 patients with infantile esotropia were reviewed and analyzed with reference to the literature.

RESULTS

All 3 patients with infantile esotropia were diagnosed with 25 to 30 PD of esotropia before the age of 6 months. All of them had insignificant refractive errors. Against medical advice, they were not brought in for follow-up examinations. At the age of 34 months to 59 months, the esotropia of the patients had changed into exophoria, esophoria less than 4 PD, or orthophoria. All patients eventually showed dissociated vertical deviation and overaction of the inferior oblique muscles. Of the 2 cooperative patients, 1 consistently identified Titmus stereograms with 3000 seconds of arc and fused Worth 4 dots at near and at distance. The other patient could not identify stereo targets and suppressed one eye on Worth 4 testing at distance, though she showed no suppression at near.

CONCLUSION

In these cases, infantile esotropia with a relatively small angle may spontaneously resolve without any treatment. However, all these patients showed poor stereoacuity, dissociated vertical deviation, and overaction of the inferior oblique muscles.

A case of Marcus Gunn jaw winking and pseudo inferior oblique overaction

PURPOSE

To report the association of Marcus Gunn jaw-winking phenomenon and pseudo inferior oblique overaction.

METHODS

Case report.

RESULTS

A 21-year-old woman presented with right eyelid elevation on the chewing movement since infancy. Examination showed that both Marcus Gunn jaw-winking phenomenon and pseudo inferior oblique overaction coexist in this patient.

CONCLUSION

The association of Marcus Gunn jaw winking and pseudo inferior oblique overaction in one patient is reported. This coexistence in our case may provide some support to the existing concept that both phenomena are caused by an ocular aberrant innervation.

Complete visual recovery in osteopetrosis by early optic nerve decompression

Visual loss with optic atrophy is common in osteopetrosis. The efficacy of optic nerve decompression in patients with osteopetrosis is still controversial. The purpose of this study is to report that visual deterioration in osteopetrosis can be completely reversed by early optic nerve decompression. An 8-year-old female patient with osteopetrosis was found to have reduced visual acuity on routine ophthalmologic examination. Extensive optic nerve decompression was performed. It not only included unroofing the optic canal, but also drilling away bone on both sidewalls of the optic nerve. Both optic nerves were decompressed during the same surgical procedure. Progressive loss of vision associated with osteopetrosis can be prevented by optic nerve decompression in the early stage of visual deterioration. When managing patients with osteopetrosis, the importance of careful and regular assessment of visual function should be stressed.

Inhibitory effect of esculetin on oxidative damage induced by t-butyl hydroperoxide in rat liver

Increasing evidence regarding free radical-generating agents and inflammatory processes suggests that accumulation of reactive oxygen species can cause hepatotoxicity. A short-chain analog of lipid hydroperoxide, t-butyl hydroperoxide (t-BHP), can be metabolized to free radical intermediates by cytochrome P-450 in hepatocytes, which in turn can initiate lipid peroxidation, affect cell integrity and result in cell injury. In this study, we used t-BHP to induce hepatotoxicity in vitro and in vivo and determined the antioxidative bioactivity of esculetin, a coumarin compound. Our investigations showed that pretreatment with esculetin (5-20 microg/ml) significantly decreased the leakage of lactate dehydrogenase (LDH) and alanine transaminase (ALT), and also decreased the formation of malondialdehyde (MDA) in primary cultured rat hepatocytes induced by a 30-min treatment with t-BHP. An in vivo study in rats showed that pretreatment with esculetin (i.p.) at concentrations of 0.5 and 5 mg/kg for 5 days before a single i.p. dose of t-BHP (0.1 mmol/kg) significantly lowered the serum levels of the hepatic enzyme markers (ALT and AST) and reduced oxidative stress in the liver. Histopathological evaluation of the rat livers revealed that esculetin reduced the incidence of liver lesions induced by t-BHP, including hepatocyte swelling, leukocyte infiltration, and necrosis. Based on the results described above, we speculate that esculetin may play a chemopreventive role via reducing oxidative stress in living systems.

A family with Leber's hereditary optic neuropathy with mitochondrial 11778/ND4 and 4216/ND1 mutations

Leber's hereditary optic neuropathy (LHON) is caused by a point mutation in the mitochondrial deoxynucleic acid (mtDNA) and accounts for 30% of bilateral optic atrophy of unknown etiology. The authors found a Korean family with mtDNA mutations in the nucleotide positions (np) 11778 and np 4216. This is the first report confirming a secondary mtDNA np 4216 mutation in Koreans, as well as the first report of a Korean family harboring both primary and the secondary mutations that the authors are aware of.

Combined effect of polytetrafluoroethylene and 5-fluorouracil on delayed adjustable strabismus surgery

PURPOSE

To determine a more reliable method for performing delayed suture adjustment to prevent the formation of postoperative adhesions and delay the time of adjustment.

METHODS

Thirty-two rabbit eyes were divided into three groups. After recession of the superior rectus muscle, 5-fluorouracil (5-FU) was administered beneath and over the superior rectus muscle in group 5-FU (12 eyes); polytetrafluoroethylene (PTFE) and 5-FU were administered in group P-f (10 eyes); and PTFE, 5-FU, and Viscoat (chondroitin sulfate, sodium hyaluronate, Alcon Laboratories Inc, Fort Worth, Tex) were administered in group P-fv (10 eyes). Delayed adjustment was performed once on each superior rectus muscle at 1, 2, and 3 weeks postoperatively in group 5-FU and at 2 and 4 weeks postoperatively in groups P-f and P-fv. The length and force for the adjustment and the degree of adhesions were recorded.

RESULTS

The use of fluorouracil allowed adjustment to be delayed up to 1 week after surgery in three of four eyes. The combined use of PTFE and 5-FU or addition of Viscoat allowed adjustment to be delayed for up to 4 weeks after surgery in four of five eyes.

CONCLUSION

The combined use of PTFE, 5-FU and Viscoat is useful for delaying suture adjustment in rabbit eyes.

Cloning and functional characterization of a Caenorhabditis elegans muscarinic acetylcholine receptor

A cDNA clone encoding a muscarinic acetylcholine receptor (mAChR) has been isolated from the nematode Caenorhabditis elegans. The nematode mAChR, consisted of 585 amino acids, displays a high degree of amino acid sequence homology to other invertebrate and vertebrate mAChRs. Excluding a highly variable middle portion of the third intracellular loop, the C. elegans mAChR shares about 51% amino acid sequence identity with a Drosophila mAChR and 42-44% identity with human m1-m5 mAChR subtypes. Comparison of the cDNA sequence with the corresponding genomic sequence reveals that the C. elegans mAChR gene contains ten introns, eight of them in the coding region. Pharmacological profiles of the C. elegans mAChR expressed in Chinese hamster ovary (CHO) cells were shown to be similar to those of mammalian counterparts, indicating that ligand binding domains of the receptor have been conserved during evolution. When this cloned receptor was expressed in Xenopus oocytes, acetylcholine evoked a transient Cl- current. Furthermore, activation of the receptor with oxotremorine, acetylcholine or carbachol resulted in the stimulation of phosphatidylinositol metabolism in CHO cells, suggesting that the receptor is coupled to phospholipase C activation.

Inhibitory effect of 12-O-tetradecanoylphorbol-13-acetate-caused tumor promotion in benzo[a]pyrene-initiated CD-1 mouse skin by baicalein

The effects of topical application of baicalein on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced promotion of skin tumors, hyperplasia, ornithine decarboxylase activity, and inflammation were evaluated in female CD-1 mice. Topical application of baicalein (0.08, 0.16, or 0.2 mumol) with TPA (5 nmol) twice weekly for 24 weeks to mice previously initiated with benzo[a]pyrene inhibited the number of TPA-induced tumors per mouse significantly. Preapplication of the same amount of baicalein also afforded significant protection against TPA-induced hyperplasia in the ear skin. Topical application of baicalein inhibited tumor promoter-caused induction of epidermal ornithine decarboxylase activity by TPA (5 nmol). The topical application of baicalein (0.008, 0.016, or 0.02 mumol) inhibited TPA-induced edema of mouse ears by 88%, 96%, or 97%, respectively. Pretreatment of mouse skin with various amounts of baicalein caused inhibition of H2O2 and myeloperoxidase formation by TPA. These results indicate that baicalein can be a potential cancer-chemopreventive agent against tumor promotion.

The relationship between stereopsis and monocular optokinetic optokinetic nystagmus after infantile cataracts

PURPOSE

Visual deprivation disrupting binocular development, such as that occurring with congenital cataract, is reported to cause asymmetric monocular optokinetic nystagmus (MOKN), as well as poor sensory and motorfusional outcome. We wanted to determine if symmetric MOKN could develop in cases of congenital cataract with good fusional outcome.

METHODS

We tested MOKN (with video and electro-oculographic recordings) and stereoacuity on 5 patients with good visual acuity and satisfactory ocular alignment after surgery for congenital cataract.

RESULTS

Stereoacuity was better than 50 seconds of arc in 1 case of monocular cataract and 2 cases of bilateral cataract. These case patients had symmetric MOKN. In a monocular cataract case, symmetric MOKN was observed in spite of questionable stereoacuity (at least 500 arc/s). One patient showed asymmetric MOKN, despite good visual acuity, and stereoacuity of 200 arc/s.

CONCLUSIONS

Patients with congenital cataract can have symmetric MOKN and good stereopsis. These cases suggest that MOKN symmetry develops along with good stereopsis, but the quality of stereopsis necessary for development of MOKN symmetry remains unclear.

A randomized comparison of prism adaptation and augmented surgery in the surgical management of esotropia associated with hypermetropia

OBJECTIVE

To compare both motor and sensory surgical outcomes for patients with esotropia associated with hypermetropia managed with an augmented surgery based on the average of the near deviation with and without correction vs preoperative prism adaptation.

METHODS

Forty-three patients with esotropia associated with hypermetropia entered a randomized prospective evaluation of augmented surgery (group A, 27 patients) versus prism adaptation (group P, 16 patients). The formula for augmenting the amount of the rectus muscle recession was based on the average of the near deviation with and without correction in group A, and the prism-adapted angle of deviation in group P.

RESULTS

In group A, postoperative deviations of 8 prism diopters (delta) or less at distance and at near were achieved in 24 patients (88%), and in 22 patients (81%), respectively. In nine prism responder patients, postoperative deviations of 8 delta or less at distance and at near were achieved in eight patients (89%). In seven nonresponder patients, postoperative deviations of 8 delta or less at distance and at near were achieved in six patients (86%). No significant difference between the two groups in terms of near and distance deviation at 1 and 3 months postoperatively were noted.

CONCLUSION

No significant difference existed in the motor outcomes between the two groups, or between the prism responder and prism nonresponder groups. Further detailed studies must be made in a large number of patients.

Combined effect of Interceed and 5-fluorouracil on delayed adjustable strabismus surgery

AIMS/BACKGROUND

To discover a more reliable method of performing delayed suture adjustment as a basis to investigate whether delayed adjustment actually provides more stable results. In order to prevent the formation of postoperative adhesions and delay the time of adjustment, an animal study was performed to determine the combined effect of physical barriers, Viscoat and Interceed, and a pharmacological agent, 5-fluorouracil (5-FU).

METHODS

38 rabbit eyes were divided into three groups. After recession of the superior rectus muscle (SRM), 5-FU was applied beneath and over the SRM in group 5-FU. Group I-f had Interceed and 5-FU and group I-fv, Interceed, 5-FU, and Viscoat. Delayed adjustment was performed once on each SRM at 1, 2, and 3 weeks postoperatively. The possible length and the necessary force to adjust as well as the degree of adhesions were recorded.

RESULTS

5-FU delayed the adjustment for up to 1 week after surgery in three out of four eyes. Combined use of Interceed and 5-FU could delay the adjustment for up to 1 week after surgery in three out of five eyes. Addition of Viscoat could delay the adjustment for up to 1 week after surgery in four out of five eyes. Adjustment was possible on only one of four eyes thereafter.

CONCLUSIONS

Combined use of Interceed, 5-FU, and Viscoat could delay the adjustment in rabbits until 1 week postoperatively.

Protective effects of capillarisin on tert-butylhydroperoxide-induced oxidative damage in rat primary hepatocytes

Capillarisin (Cap), a main constituent of Artemisia capillaris (Compositae), was studied for its antioxidant bioactivity. In the preliminary study, Cap expressed a antioxidant property by its capacity for quenching the free radicals of 1,1-diphenyl-2-picrylhydrazyl (DPPH). This antioxidant bioactivity of Cap was investigated further using a model of t-butylhydroperoxide (t-BHP)-induced cytotoxicity and genotoxicity in rat primary hepatocytes. Results presented here demonstrate that Cap, at concentrations of 0.01-1.00 mg/ml, significantly decreased the leakage of lactate dehydrogenase (LDH) and alanine aminotransferase (ALT) and the formation of malondialdehyde (MDA) induced by 30 min treatment of t-BHP (1.5 mM) in primary cultured rat hepatocytes. Cap also attenuated the t-BHP-induced diminution of glutathione (GSH) and high level of DNA repaired synthesis. These results lead to speculation that Cap presents inhibitory effects against t-BHP-caused cytotoxicity and genotoxicity in rat primary hepatocyte cultures at least via two distinct pathways, stabilizing the GSH system and quenching free radicals.

The Lancaster red-green test before and after occlusion in the evaluation of incomitant strabismus

BACKGROUND

Patients with incomitant strabismus can often fuse in a limited area of gaze. Prolongation of neurologically learned fusional vergence tone ("vergence adaptation") in and near this area can result in misleading measurements with standard clinical measures of strabismus. Monocular occlusion for at least 30 minutes eliminates most of the effect of vergence adaptation. The Lancaster red-green test provides an elegant and convenient map of incomitant strabismus. We investigated the efficacy of the Lancaster red-green test before and after monocular occlusion for the investigation of incomitant strabismus.

METHODS

We retrospectively studied the results of the Lancaster red-green test in 6 patients with incomitant vertical strabismus in whom we suspected that vergence adaptation might be distorting the pattern of deviation. The test was performed before and after monocular occlusion for 30 to 60 minutes, and the preocclusion and postocclusion results were compared.

RESULTS

In the 6 cases studied, the Lancaster red-green test showed at least a 5-PD increase in the hyperdeviation, after monocular occlusion. The increases were mostly in primary gaze and downgaze, which tended to regularize the pattern of deviation.

CONCLUSIONS

The combination of monocular occlusion and the Lancaster red-green test is useful for uncovering the effect of vergence adaptation. Such results may often simplify the planning of surgical correction because the incomitance usually decreases after monocular occlusion, making it less likely that surgery will worsen the alignment in the area previously fused. We recommend that monocular occlusion should be considered when planning surgery or even prism correction for incomitant deviations, especially when the initial Lancaster red-green test shows an unexpected incomitant pattern where there is fusion in 1 direction of gaze but not in others.

Cloning and expression of a G protein-linked acetylcholine receptor from Caenorhabditis elegans

We have isolated a cDNA clone from the nematode Caenorhabditis elegans that encodes a protein of greatest sequence similarity to muscarinic acetylcholine receptors. This gene codes for a polypeptide of 682 amino acids containing seven putative transmembrane domains. The amino acid identities, excluding a highly variable middle portion of the third intracellular loop, to the human m1-m5 receptors are 28-34%. When this cloned receptor was coexpressed with a G protein-gated inwardly rectifying K+ channel (GIRK1) in Xenopus oocyte, acetylcholine was able to elicit the GIRK current. This acetylcholine-induced current was substantially inhibited by the muscarinic antagonist atropine in a reversible manner. However, another muscarinic agonist oxotremorine and antagonists scopolamine and pirenzepine had little or negligible effects on this receptor. Taken together, these results suggest that the cloned gene encodes a G protein-linked acetylcholine receptor that is most similar to but pharmacologically distinct from muscarinic acetylcholine receptors.

Bilateral ocular ischemic syndrome secondary to giant cell arteritis progressing despite corticosteroid treatment

PURPOSE

To report the development of a bilateral ocular ischemic syndrome despite corticosteroid treatment in a patient with giant cell arteritis.

METHOD

Case report.

RESULTS

Despite receiving high-dose intravenous methylprednisolone and oral prednisone for biopsy-proven giant cell arteritis that presented as a severe anterior ischemic optic neuropathy in the right eye, a patient developed progressive ocular ischemia in that eye as well as an ocular ischemic syndrome in the fellow eye.

CONCLUSIONS

Some patients with giant cell arteritis, possibly patients with other underlying systemic vasculopathies, are refractory to what should be adequate treatment with systemic corticosteroids and may develop a bilateral ocular ischemic syndrome.

Results and prognostic factors in the retreatment of locally recurrent nasopharyngeal carcinoma

PURPOSE

To review the results and evaluate the prognostic factors in the retreatment of locally recurrent nasopharyngeal carcinoma.

METHODS AND MATERIALS

We reviewed the records of 74 patients with locally recurrent nasopharyngeal carcinoma treated at the University of California, San Francisco between 1957 and 1995. The histologic types included squamous cell carcinoma in 6 (8.1%), nonkeratinizing carcinoma in 48 (64.9%), and undifferentiated carcinoma in 20 (27%) cases. The site of recurrence was in the primary in 46 (62.2%), in the neck nodes in 20 (27%), and in both sites in 8 (10.8%) patients. The recurrent disease was Stage I in 10 (13.5%), Stage II in 16 (21.6%), Stage III in 20 (27%), and Stage IV in 28 (37.9%) patients. Thirty-seven (50%) patients developed recurrence within 2 years and 58 (78.4%) within 5 years after initial treatment. Radiotherapeutic techniques used in the retreatment of primary recurrence consisted of external beam radiotherapy (EBRT), intracavitary brachytherapy, heavy-charged particle beam, and gamma knife, alone or in combination. Reirradiation doses ranged from 18 to 108 Gy, with a median dose of 60 Gy. Treatment of recurrent neck nodes consisted of radical neck dissection (RND) +/- intraoperative radiotherapy (IORT), or EBRT +/- hyperthermia, or chemotherapy +/- hyperthermia. Chemotherapy was used in 22 (30%) patients. Median follow-up was 20 months (range: 2 to 308 months).

RESULTS

The 3-, 5-, and 10-year actuarial overall survival following retreatment were 49, 37, 18%, respectively. Thirty-six patients (49%) were free of further local-regional recurrence after retreatment. The 3-, 5-, and 10-year local-regional progression-free rates were 52, 40, and 38%, respectively. On univariate analysis, histologic type (p < 0.0001), interval to recurrence (p = 0.034), and treatment modality for early-stage disease (p = 0.01) were significant prognostic factors for overall survival, with age being marginally significant (p = 0.053). For local-regional progression-free rate, only histology was significant (p = 0.035). On multivariate analysis, age (p = 0.026), histology (p = 0.015), and interval to recurrence (p = 0.030) were significant for overall survival, and only histology (p = 0.002) and presence of complications (p = 0.016) were significant for local-regional progression-free rate. Of the 64 reirradiated patients, late complications were documented in 29 (45%) patients. The late complications were permanent in 21 (33%) and severe in 15 (23%) patients.

CONCLUSION

Retreatment using radiotherapy alone or in combination with other treatment modalities can achieve long-term local-regional control and survival in a substantial proportion of patients with locally recurrent nasopharyngeal carcinoma. Age, histology, and interval to recurrence were independent prognostic factors for overall survival, but only histology and presence of complications were significant for local-regional progression-free rate.

Optic neuropathy associated with ethambutol in Koreans

Ethambutol is a useful first line antituberculous drug, but can cause significant visual impairment. In order to determine the clinical manifestations of optic neuropathy associated with ethambutol, and the margin of drug safety in Koreans, we investigated ten men and four women, diagnosed between 1995 and 1997 at Seoul Municipal Boramae Hospital as suffering from ethambutol toxicity. After determining their history, including the period during which ethambutol had been administered, and its dose, a complete eye examination was performed, including measurement of best-corrected visual acuity, pupillary examination, color vision, fundus examination and a test of visual field. Ocular ethambutol toxicity was observed at a dose as low as 12.3 mg/kg. Abnormal ophthalmic findings include decreased visual acuity and abnormal visual field, especially in the central scotoma, and abnormal color perception. In conclusion, ethambutol at a low dose can cause optic neuropathy, and for the early detection of this, a color vision test is important.

Optic neuropathy associated with mitochondrial tRNA[Leu(UUR)] A3243G mutation

PURPOSE/BACKGROUND

To report the association of optic neuropathy and mitochondrial tRNA[Leu(UUR)] A3243G mutation which is known to be responsible for MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes), diabetes mellitus with deafness, and progressive external opthalmoplegia. Pigmentary retinopathy, opthalmoparesis, and ptosis have been relatively frequently reported to be associated with the mutation in the literature. However, optic atrophy has rarely been reported to be associated with the mutation.

METHODS

Analyses including measurement of the corrected visual acuity, color vision, pupillary examination, funduscopic examination, visual field, visual evoked potential, and brain imaging study were performed in our two patients with the mutation.

RESULTS

In disagreement with previous reports, this study revealed the association between optic neuropathy and the mutation in the two patients.

CONCLUSION

There might be some degree of optic neuropathy related to the tRNA[Leu(UUR)] A3243G mutation. Thus more detailed ophthalmologic examination should be done to detect optic neuropathy.

Nucleotide sequence and phylogenetic analysis of Newcastle disease virus isolates from recent outbreaks in Taiwan

Portions of the hemagglutinin neuraminidase (HN) gene of Newcastle disease virus (NDV) isolates from two recent outbreaks were sequenced to investigate epidemiology of this disease in Taiwan. These NDV isolates were all viscerotropic velogenic according to the clinical lesions produced in chickens. Sequence data were obtained from 14 NDV isolates (12 from 1995 and 2 from 1984). All isolates differed in their nucleotide sequences (from 0.3 to 15.3%), and represented potentially different strains of NDV. Phylogenetic analysis revealed that these isolates are closely related to viruses isolated from Japan and Malaysia. Some viruses isolated in 1995 appeared to evolve from viruses isolated in 1984. The results suggest that the 1995 outbreak of Newcastle disease (ND) in Taiwan may have been caused by multiple strains of velogenic NDV that have cocirculated in Taiwan for some time. Moreover, NDV isolates from racing pigeons were very similar to isolates from chickens in the same period, suggesting that both domestic and free-living birds were involved in the spread of ND in Taiwan.

The microevolution of mouse salivary androgen-binding protein (ABP) paralleled subspeciation of Mus musculus

Mouse salivary androgen-binding protein (ABP) is a major secretory product of the submaxillary glands. Although it is a common salivary protein among rodents generally, the function of ABP has yet to be determined. Here we report a comparison of the DNA coding sequences and putative amino acid sequences they determine for the three common alleles of the Alpha subunit gene (Abpa), alleles that appear to be diagnostic for the three subspecies of Mus musculus. Three other unique sequences were found in the species M. caroli, M. spretus, and M. spicilegus. Comparison of the six sequences shows that 8 of the 20 base substitution sites produce a high degree of variability in amino acids 32, 33, 36, and 39, a variability that creates unique sequence combinations in each species and subspecies. We compare the possibilities that selection or genetic drift caused this unusual microevolution and argue that selection is the more likely explanation. We speculate on the potential significance of this with respect to the proposal that ABP is involved in assortive mate kin selection.

Delayed reattachment of extraocular muscles in rabbits using thin polytetrafluoroethylene

BACKGROUND AND OBJECTIVE

The authors attempted to find a way to perform reliable delayed suture adjustment so that surgeons can investigate whether delayed adjustment actually gives more reliable and stable results. To prevent the formation of postoperative adhesions and delay the time of adjustment, the authors used polytetrafluoroethylene (PTFE) as a mechanical barrier.

MATERIALS AND METHODS

PTFE was placed between the free muscle end and the sclera as a physical barrier in 16 rabbits.

RESULTS

PTFE could delay the adjustment for up to 4 weeks after surgery in 4 of 10 eyes in each group. After removal of PTFE, adjustment was possible up to 12 weeks because there was no adhesion between the muscle and the PTFE.

CONCLUSION

Adjustment could be delayed up to 4 weeks in 40% of the experimental eyes using PTFE as a physical barrier.

Carbon monoxide poisoning as an epigenetic factor for Leber's hereditary optic neuropathy

A 45-year-old Korean woman visited our hospital complaining of poor vision after carbon monoxide (CO) poisoning. We have confirmed the presence of a point mutation at position 11778 in the ND4 gene of mitochondrial DNA. This case suggests that CO poisoning may precipitate the clinical expression of Leber's hereditary optic neuropathy (LHON). To our knowledge, this would be the first case report of clinical expression of LHON precipitated by CO poisoning.

Inhibitory effect of atractylon on tert-butyl hydroperoxide induced DNA damage and hepatic toxicity in rat hepatocytes

Atractylon, a main sesquiterpenic constituent of Atractylodes rhizomes, was studied for the mechanism of its inhibitory effects on the tert-butyl hydroperoxide (t-BHP)-induced cytotoxicity and lipid peroxidation in primary culture of rat hepatocytes. In the preliminary study, atractylon showed an effective antioxidant property tested by its capacity for quenching 1,1-diphenyl-2-picrylhydrazyl radical (DPPH). Further investigations showed that atractylon at the concentrations of 0.01, 0.1 and 1.0 mg/ml decreased the formation of malondialdehyde (MDA), leakage of lactate dehydrogenase (LDH) and alanine aminotransferase (ALT) and repair synthesis of DNA induced by 30-min treatment of t-BHP (1.5 mM) in primary cultured rat hepatocytes. Addition of atractylon also attenuated the genotoxicity of t-BHP evaluated by unscheduled DNA synthesis. The sum of the results suggested that the protective effect of atractylon against oxidative stress induced by t-BHP is via its ability to quench free radicals.

Use of physical barriers for delayed adjustable strabismus surgery: the effect of interceed and polyglactin 910 mesh

AIMS/BACKGROUND

In the course of adjustable strabismus surgery there is only a limited period after surgery before the formation of firm adhesions prevents successful adjustment. To determine if this period could be increased by the interposition of suitable physical barriers, the use of Interceed and polyglactin 910 mesh was investigated in an animal model.

METHODS

A total of 39 rabbit eyes were divided into three groups. After recession of the superior rectus muscle (SRM), balanced salt solution was applied to the control group between the free muscle end and the sclera; in each of the two experimental groups, Interceed and polyglactin 910 mesh were applied. Delayed adjustment was performed once on each SRM at 1, 2, or 3 weeks postoperatively. The length and force of the adjustment, the degree of adhesions, and the degree of fibrous proliferation were recorded.

RESULTS

Adjustment was not possible in any of the eyes in the control group. At 1 week postoperatively, adjustment was possible in four out of five eyes with Interceed and in three out of five eyes with polyglactin 910 mesh as a physical barrier.

CONCLUSIONS

Interceed may be clinically useful in delaying the timing of adjustment up to 1 week. Further study of the use of other materials could be carried out to see if it was possible to delay the timing of adjustment for more than 1 week.

Concurrent 5-fluorouracil, daily low-dose cisplatin, and radiotherapy in stage IIIB cervical cancer. A phase II prospective study

Between June 1987 and May 1991, 30 patients with Stage IIIB cervical cancers were treated using synchronous radiotherapy, 5-fluorouracil (5-FU), and daily low-dose cisplatin. External radiotherapy (3,600-3,960 cGy) was given to the whole pelvis in 4 weeks. Two courses of intracavitary brachytherapy were given 2 weeks later. Parametrial boost was then given. Continuous infusion of 5-FU 750 mg/m2 was given for 5 days during the first and third week of pelvic irradiation. Cisplatin (6 mg/m2) was given 30 min before every irradiation in the second and fourth week. The complete response rate was 87%. The 3-year local control rate was 77%. The 3-year overall and disease-free survival rate was 66% and 56%, respectively. Distant metastases were the major causes of treatment failure. Toxicities were acceptable. Our preliminary results indicate that this synchronous combination treatment is feasible. Further follow-up is required to determine whether this regimen has a genuine favorable impact on survival and chronic toxicity.

Complete nucleotide sequence, structural organization, and an alternatively spliced exon of mouse h1-calponin gene

From a CC1.2 embryonic stem cell genomic library, we isolated and sequenced a 10.4-kb DNA segment (GenBank/EMBL Data Bank accession number L49022) containing the entire gene encoding mouse h1-calponin, an actin-associated smooth muscle-specific protein and a potential modulator of contraction. Sequence data revealed that there are seven exons and six introns in the h1-calponin gene. Determined by primer extension mapping of the RNA transcripts, the transcription of h1-calponin gene initiates at the same site in stomach, urinary bladder and pregnant uterus smooth muscles. The genomic organization suggests that the previously identified alpha- and beta-calponin isoforms are produced by splicing of exon 7 at two alternative acceptor sites. Isolation and structural characterization of the h1-calponin gene provides information to further investigate the expression regulation of this smooth muscle-specific gene.

Combined study on the causes of strabismus after the retinal surgery

Extraocular muscle imbalance and diplopia after retina surgery have been previously reported, but the etiology is still controversial. In order to better understand the cause of strabismus after retinal surgery, the authors retrospectively studied 30 patients with persistent strabismus following retinal surgery and combined the result about seven patients of strabismus after retinal surgery in the previous report. Results showed multiple etiologies for the strabismus. Causes of strabismus included fat adherence syndrome (14 patients), non-specific restrictive adhesion (11), displacement of superior oblique tendon (2), scleral explant interfering with ocular motility (1), lost or slipped muscle with adhesion (2), sensory strabismus (2), macular pucker causing ectopic fovea (2), and previous strabismus before the retinal surgery (3). Knowledge of the varieties of abnormalities that can cause strabismus and diplopia will help both the retina and strabismus surgeon prevent and treat strabismus after retinal surgery.

Surgical techniques of strabismus

Improvements in the management of strabismus are largely dependent on making the specific diagnosis and differentiating patterns of strabismus. This finding is especially true in the management of superior oblique paresis because there are various types. Recent observation suggests that superior oblique paresis may be associated with a lax superior oblique tendon and that the cause of the paresis is not always neurogenic. Some authorities have suggested using the traction test of the superior oblique to determine whether the superior oblique tendon is lax. If it is lax, the treatment of choice would be a tightening procedure of the superior oblique such as the superior oblique tuck. Adjustable-suture strabismus surgery has reduced the incidence of repeat operations; however, adapting the procedure to the fornix incision has been difficult. The use of a scleral traction suture that retracts the conjunctiva to expose the muscle suture area has been useful for fornix surgery. The rectus muscles supply circulation to the anterior segment via the anterior ciliary vessels, which are routinely interrupted during strabismus surgery. Various procedures have recently been described to preserve the anterior ciliary vessels, and these procedures will be useful in patients who are predisposed to anterior segment ischemia. In the 1950s, inferior oblique weakening procedures were deemed dangerous and unpredictable. Recent advances in the understanding of inferior oblique physiology and fascial relationships have inspired the development of a new inferior oblique weakening strategy--the anteriorization procedure.(ABSTRACT TRUNCATED AT 250 WORDS)