Eye injuries in a terrorist bombing: Dhahran, Saudi Arabia, June 25, 1996

OBJECTIVE

We report the experience of our institution in the evaluation and care of multiple simultaneous ocular trauma patients after a terrorist bomb attack on a United States military base in Saudi Arabia.

DESIGN

Retrospective, noncomparative small case series.

PARTICIPANTS

Three patients who received severe ocular injuries after a terrorist bombing.

INTERVENTION

All patients underwent surgical repair of the injuries that were inflicted as a result of the terrorist bombing.

MAIN OUTCOME MEASURES

Baseline ocular characteristics, intraoperative findings, surgical procedures, and final (3 years after injury) anatomic and visual outcomes were noted.

RESULTS

Glass fragments caused by the blast were the mechanism of all the ocular injuries in these patients. All patients had primary repair of the injuries done in Saudi Arabia and were sent to our institution for tertiary care. Three of the four eyes injured had stable or improved visual acuity and one eye was enucleated. Two patients had no serious injury other than the globe trauma. One patient had extensive eyelid trauma and required serial procedures to allow fitting of a prosthesis.

CONCLUSIONS

Blast-injury patients are at risk for open globe injury as a result of glass fragments. The types of injury that can occur from terrorist blasts can be extensive and involve all the tissues of the eye, the ocular adnexa, and the orbit.

Posterior chamber intraocular lens use in children

PURPOSE

The authors report on the efficacy of intraocular lens implantation during pediatric cataract surgery and the results of a consecutive series of intraocular lens implantation in children.

METHODS

Twenty-one children underwent implantation of intraocular lenses in 23 eyes. Twenty-one surgeries were primary implantation immediately following anterior lensectomy. Two surgeries were secondary implantations. Primary posterior capsulectomy was performed in 18 of 21 primary implantations. All but two eyes underwent a primary anterior vitrectomy. Topical prednisolone acetate was administered in all cases. Oral prednisone was administered in 17 of 23 cases. Pre- and postoperative visual acuity, cycloplegic refraction, and postoperative complications related to inflammation such as intraocular lens (IOL) capture, IOL decentration, and posterior capsule opacification were examined.

RESULTS

Eighteen of 23 eyes have achieved a visual acuity of 20/40 or better. None of the cases in which oral prednisone was used developed complications related to postoperative inflammation. One of the six cases (17%) in which oral prednisone was not used developed such complications.

CONCLUSION

Intracular lens implantation accompanied by primary posterior capsulectomy, anterior vitrectomy, and management of postoperative inflammation appears to provide appropriate and safe optical rehabilitation in children.

Treatment of Nocardia asteroides keratitis with polyhexamethylene biguanide

PURPOSE

Polyhexamethylene biguanide (PHMB) is a polymeric biguanide disinfectant that has been used previously in the treatment of Acanthamoeba keratitis. The authors report the first case of Nocardia asteroides keratitis treated successfully with PHMB. Further studies documenting the efficacy of PHMB against N. asteroides in vitro also are presented.

METHODS

A soft contact lens wearer presented with an infectious keratitis. Cultures from the cornea grew N. asteroides. The infection resolved with the treatment with PHMB 0.02%. Serial dilutions of PHMB were performed against N. asteroides in culture.

RESULTS

In vitro dilution studies determined that the minimal inhibitory concentration for PHMB against the tested isolate of N. asteroides was 0.01%. This is a concentration that has been shown to be well tolerated by the cornea in vivo.

CONCLUSIONS

Polyhexamethylene biguanide is effective against both Acanthamoeba and Nocardia and may have a wider range of usefulness than that currently recognized. Further testing, both in vitro and in vivo, is required.

Induction of metallothionein mRNA and protein in primary murine neuron cultures

Metallothionein (MT)-I and -II are present in most if not all cells of the body and are readily inducible both in vivo and in vitro. MT-III is present only in brain, primarily in neurons, and is seemingly not inducible. Because it is difficult to determine whether inducing agents reach neurons (in vivo) in sufficient concentrations, it was of interest to directly test the inducibility of MT-III in vitro. A further objective was to examine the inducibility of MT-I and -II so that comparisons could be made to responses in glial cells. Cultures were established from fetal (Days 14-17) CF-1 mice. Cells were treated after they achieved a mature phenotype (around 6 days) with various concentrations of the following MT inducers: dexamethasone (Dex), cadmium (Cd), zinc (Zn), or inorganic mercury (Hg). MT protein was quantified by the Cd-hemoglobin assay at 24, 48, 72, 96, and 120 hr. All inducers produced significant increases in MT protein between 24 and 96 hr. MT protein increased in a dose-dependent manner, and maximum (up to 6-fold over controls) increases were seen at 3, 30, 100, and 1000 microM for Cd, Hg, Zn, and Dex, respectively. The expression of MT-I, -II, and -III mRNA was examined by dot-blot analysis 6 hr following the addition of inducers at concentrations known to maximally stimulate the induction of MT protein. Zinc and Cd produced 2.5 to 3.5-fold increases in MT-I and -II mRNA, whereas Dex and Hg produced 1.5- to 2.5-fold increases. However, all inducers assayed decreased MT-III mRNA about 30-60%. The present results indicate that MT-I and -II are inducible in neurons as they are in astrocytes, but the basal level and induced level of MT protein is about one-third in neurons as in astrocytes. Unlike MT-I and -II, MT-III is apparently not inducible under the present experimental conditions.

Induction of metallothionein mRNA and protein in murine astrocyte cultures

Astrocytes are known to express metallothionein (MT) and were studied in culture to determine whether MT could be directly induced and which isoforms are induced. Primary astrocyte cultures were established from neonatal CF-1 mice. Both concentration-response and time-course analyses for MT induction at the protein level were determined. At the mRNA level, induction of MT-I, -II, and -III was examined 6 hr following the addition of the inducing agents. Dexamethasone (Dex), cadmium (Cd), mercury (Hg), or zinc (Zn) increased (three- to fourfold) MT protein in the astrocytes, whereas methyl mercury, lead, and interleukin-1 and -6 were ineffective. Cadmium was the most potent inducer, but was not more effective than Hg or Zn in inducing MT protein. All effective inducers increased MT protein by 24 hr. After 48 hr, Hg caused cell death, but all other effective inducers increased the MT protein examined over the 5 days. Cadmium induction of MT protein reached a peak at 96 hr, whereas the other effective inducers stimulated maximal MT protein at 24-48 hr. The effects of Dex, Cd, and Zn, on MT-I, -II, and -III mRNAs were also examined. Cadmium, Zn, and Dex stimulated increases in both MT-I and MT-II mRNA, with Dex producing the greatest effect (2.0- and 3.5-fold for MT-I and -II mRNA, respectively). Metallothionein-III mRNA was relatively unresponsive to induction. Therefore, Cd, Zn, and Dex induced MT-I and -II mRNA but not MT-III mRNA in astrocytes. These results demonstrate that MT-I and -II are directly induced in mouse astrocyte primary cultures.

Constitutive expression of metallothionein genes in mouse brain

Metallothioneins (MTs) are ubiquitous low-molecular-weight proteins that are induced by a variety of inducers, including metals, lipopolysaccharides (LPS), cytokines, oxidative stress, etc., and are thought to play a protective role against various toxic insults. The constitutive level of metallothionein is an important determinant of a tissue's susceptibility to toxic insults. In the present study, we report the constitutive expression of MT mRNAs in adult mouse brain. Analysis of total RNA from whole brain by Northern blot and solution hybridization showed that mRNAs for all three MT isoforms (I, II, III) were constitutively expressed in mouse brain, and there was no remarkable difference in their expression. However, in quantitative terms the order of expression was MT-I > MT-III > MT-II. The expression of MT-III and MT-II was about 70 and 50% of that of MT-I, respectively. Examination of their constitutive expression in different brain regions revealed that the three isoforms were expressed in all seven brain regions studied (olfactory bulb, cortex, caudate, hippocampus, thalamus, cerebellum, and brain stem), and there was only about a twofold difference in MT mRNA expression from one region of the brain to another. However, olfactory bulb had the highest mRNA expression for all three isoforms, as revealed by slot blot analysis. Constitutive expression of MT-I and -II mRNA, but not MT-III mRNA, was high in cerebellum. In order to study the cellular localization of MT mRNA, in situ hybridization of MT-I and MT-III mRNA was performed. For comparison, LPS was used to enhance MT-I mRNA signal because LPS is a good inducer of MT-I mRNA expression in mouse brain. In situ hybridization revealed that certain brain regions had distinctly localized high levels of expression of MT mRNAs. In brains of untreated mice, the constitutive expression of MT-I mRNA was high in the ependymal cell layer lining the lateral ventricles and in the Purkinje cell layer of cerebellum. The signal in the Purkinje cell layer was not on the Purkinje cells themselves, but was on locations consistent with that of glial cells. In LPS-treated mice, the signal in cerebellum was higher, and distinct signal appeared in the choroid plexus. However, signal in ependyma was similar to that in untreated mice. Pia mater in LPS-treated, but not in untreated, mouse brain showed enhanced signal for MT-I mRNA.(ABSTRACT TRUNCATED AT 400 WORDS)

Intraocular irrigating solutions. A randomized clinical trial of balanced salt solution plus and dextrose bicarbonate lactated Ringer's solution

BACKGROUND

Two intraocular irrigating solutions which differ principally by the presence of oxidized glutathione were compared in this randomized, masked, prospective study to discern differences in preservation of endothelial cell size.

METHODS

Sixty-four patients undergoing extracapsular cataract extractions were randomized between two irrigating solution groups, Balanced Salt Solution (BSS) Plus (n = 30) and dextrose bicarbonate lactated Ringer's solution (n = 34). Preoperative and postoperative endothelial specular photomicrographs were analyzed for cell size and hexagonality, and the two groups were compared using repeated measures analysis of variance.

RESULTS

Fifty-eight subjects (91%) completed the 2-month study. Change in cell size for the BSS Plus group (n = 28) (mean +/- standard error, 29.4 +/- 12.3 microns2) was not significantly different from the dextrose bicarbonate lactated Ringer's solution group (n = 30) (27.5 +/- 12.9 microns2) (P = 0.92). Groups did not differ significantly in percent hexagonality (P = 0.57) or in the variability of cell size (P = 0.61).

CONCLUSION

The presence of glutathione in BSS Plus and other minor electrolyte differences between the solutions is not more advantageous with regard to endothelial cell size than dextrose bicarbonate lactated Ringer's solution for standard extracapsular cataract surgery. Cost per 500-microliters bottle of BSS plus is $62 compared with $9.80 for dextrose bicarbonate lactated Ringer's solution.

Selective cloning of cDNA for secretory proteins of early embryos. Identification of a transiently expressed kunitz domain protein from preimplantation sheep trophoblast

The preimplantation ovine conceptus transiently secretes several proteins, including a type I interferon (IFN-tau), that are likely involved in establishment of pregnancy. A method has been developed to identify proteins produced simultaneously with IFN-tau. An antiserum against total ovine conceptus secretory proteins, from which IFN-tau and proteins common to maternal uterine tract secretions had first been removed, was used to immunoscreen cDNA libraries created from mRNA of days 13 and 15 ovine conceptuses. This approach has allowed several unique cDNA to be identified, including one particularly abundant transcript for a novel member of the Kunitz family of serine protease inhibitors. This cDNA encodes a 265-amino acid protein with a 20-amino acid signal sequence. A 64-amino acid Kunitz domain occupies the carboxyl terminus. It is preceded by two similar repeats of 84 residues that bear no obvious similarity to any sequences present in the protein data banks. The protein present in conceptus secretions (M(r) of approximately 14,000) represents only the carboxyl terminus of the molecule. The mRNA for this putative proteinase inhibitor was confined to trophectoderm and was highly expressed for only a few days (approximately 13-18) of development. A similar transcript was detected during the days 17-21 period in cattle embryos. Despite their high expression, no proteinase-inhibitory activity can so far be ascribed to either the ovine or bovine proteins. The P1 residue, an asparagine, is not represented in any other known Kunitz inhibitors.

Identification of the major pregnancy-specific antigens of cattle and sheep as inactive members of the aspartic proteinase family

Pregnancy in cattle and sheep can be diagnosed by the presence of a conceptus-derived antigen in maternal serum that is secreted by trophoblast and placental tissue primarily as an acidic component of Mr 67,000. Molecular cloning of its cDNA reveals that the antigen belongs to the aspartic proteinase family and has greater than 50% amino acid sequence identity to pepsin, cathepsin D, and cathepsin E. The inferred sequences of the ovine and bovine polypeptides show approximately 73% identity to each other. Critical amino acid substitutions at the active site regions suggest that both proteins are enzymatically inactive. The antigen is a product of trophoblast binucleate cells that invade maternal endometrium at implantation sites.

The retinol-binding protein of the expanding pig blastocyst: molecular cloning and expression in trophectoderm and embryonic disc

Retinol-binding protein (RBP) is a major secretory product of the porcine conceptus. Using an oligonucleotide probe corresponding to a highly conserved region of all known mammalian RBP, we have isolated an apparently full-length cDNA clone for porcine conceptus RBP from a cDNA library constructed from pig conceptuses collected between days 13-17 of pregnancy. The cDNA was 937 base-pairs in length and coded for a protein whose inferred amino-terminal sequence was identical to that reported for both porcine conceptus RBP and porcine serum RBP. Its length was consistent with the size (approximately 1 kilobase) of the RBP message in porcine conceptuses. Porcine conceptus RBP and human serum RBP share 91% amino acid sequence identity. The inferred differences in sequence were evenly distributed throughout the length of the polypeptide. RBP mRNA was detectable within the trophoblast of day 11 porcine conceptuses by in situ hybridization with a 618-basepair 35S-labeled probe corresponding to the 3' end of porcine RBP. Silver grain density was distributed relatively uniformly over the trophoblast and the inner cell mass. Western blot analysis of conceptus culture medium demonstrated that the conceptuses of cattle (on day 19) and sheep (on day 15) as well as pigs secrete RBP during early pregnancy. Secretion of large quantities of RBP by the trophoblast of preimplantation pig conceptuses suggests important roles for vitamin A and RBP near the time of conceptus elongation.

The effect of rapid freezing on uveal melanomas

We studied the immediate effects of rapid freezing on 19 variously sized uveal melanomas that were subjected to cryoenucleation using liquid nitrogen and a cryoring by light and electron microscopy and tissue culture. The freezing time and the temperature of 11 lesions were recorded. The light microscopic finding of an intranuclear clear center with peripheral displacement of clumped chromatin against the nuclear membrane was suggestive of intranuclear ice crystal formation but did not indicate cellular death of the tumors. The major ultrastructural changes, including plasmalemmal breaks, dissolution of cytoplasmic matrix, and damage to various organelles, however, suggested acute necrosis in tumors not exceeding 7 mm in elevation. Failure of the melanoma cells to grow in tissue culture and positive staining with trypan blue support the contention of tumor death. The late effects of rapid freezing were also evaluated in another case of uveal melanoma. The eye was enucleated six months after cryopexy. Histopathologic findings showed that the tumor was necrotic. Failure of the neoplasm to regress (noted clinically) was related to edema and inflammatory infiltrates.

A light-emitting diode array globe protector photostimulator

Intraoperative visual-evoked potential recording has been a potentially useful procedure for monitoring the functional status of the visual pathways during certain neurosurgical procedures. Technical problems have limited its adoption. We report a light-emitting diode array globe protector photostimulator which enhances the stimulation component of the visual-evoked potential recording technique.

Enucleation with stabilization of intraocular pressure in the treatment of uveal melanomas

The standard surgical technique for enucleation of an eye containing a malignant melanoma of the uvea elevates intraocular pressure markedly and may thereby disseminate tumor cells and cause death. It is possible to enucleate an eye bear a malignant melanoma of the choroid without elevating intraocular pressure to more than 27 mm/Hg by employing a manometric intraocular pressure regulating system and the adjustable cryo-ring. The value of this method of enucleation in diminishing tumor deaths remains unknown.

Ocular malingering and hysteria: diagnosis and management

Confronted with a claim of poor vision in the absence of any apparent pathology, the ophthalmologist must consider the possibility that the patient is malingering or hysterical. The authors define four categories of such patients, and recommend diagnostic approaches for each. Specific diagnostic tests are described, as are methods of managing patients once the diagnosis of malingering or hysteria has been made.

Quantification of intraocular malignant melanoma volume: a preliminary report

Intraocular malignant melanoma size is a significant prognostic indicator. No accurate volume determining technique has been generally utilized. Plastic models and selected geometric formulae were used to demonstrate a technique for volume calculation of intraocular malignant melanomas. The accuracy of geometric analysis is shown to be superior to previous "size" calculations. We believe this increased accuracy would be useful in following patients for tumor growth utilizing A and B scan ultrasonography as well as in quantifying tumor volumes in the histopathology laboratory.