Nostoc commune UTEX 584 gene expressing indole phosphate hydrolase activity in Escherichia coli

A gene encoding an enzyme capable of hydrolyzing indole phosphate was isolated from a recombinant gene library of Nostoc commune UTEX 584 DNA in lambda gt10. The gene (designated iph) is located on a 2.9-kilobase EcoRI restriction fragment and is present in a single copy in the genome of N. commune UTEX 584. The iph gene was expressed when the purified 2.9-kilobase DNA fragment, free of any vector sequences, was added to a cell-free coupled transcription-translation system. A polypeptide with an Mr of 74,000 was synthesized when the iph gene or different iph-vector DNA templates were expressed in vitro. When carried by different multicopy plasmids and phagemids (pMP005, pBH6, pB8) the cyanobacterial iph gene conferred an Iph+ phenotype upon various strains of Escherichia coli, including a phoA mutant. Hydrolysis of 5-bromo-4-chloro-3-indolyl phosphate was detected in recombinant E. coli strains grown in phosphate-rich medium, and the activity persisted in assay buffers that contained phosphate. In contrast, indole phosphate hydrolase activity only developed in cells of N. commune UTEX 584, when they were partially depleted of phosphorus, and the activity associated with these cells was suppressed partially by the addition of phosphate to assay buffers. Indole phosphate hydrolase activity was detected in periplasmic extracts from E. coli (Iph+) transformants.

Infantile exotropia in healthy children

Constant exotropia is uncommon during the first year of life. We retrospectively identified 13 patients with large, constant exotropia during the first year of life which required surgery. Bilateral lateral rectus muscle recessions were done in all 13 cases. Only two patients have required reoperation. The clinical characteristics and management of this unusual condition are similar to those of infantile esotropia.

Astigmatism associated with adnexal masses in infancy

High degrees of astigmatism are common in infants with hemangiomas but have not been well documented with other adnexal masses. We reviewed records of 65 patients (69 eyes) with chalazions, epibulbar or orbital dermoids, hemangiomas, and dacryoceles. Astigmatism greater than +1.25 diopters (as high as +5.50 diopters) was most commonly associated with dacryoceles (eight of 12 eyes) and with hemangiomas (14 of 17 eyes). Plus cylinder axes were consistently oriented toward the lesion, and astigmatism tended to resolve with resolution of the lesions. Only one of the 17 eyes with dermoids and two of the 23 eyes with chalazions had astigmatism. Anisometropic amblyopia has been a prominent concern in the treatment of infants with hemangiomas. Patients with dacryoceles may be at similar risk. Repeated cycloplegic refractions are important in determining appropriate treatment of adnexal masses.

Severe visual loss resulting from occlusion therapy for amblyopia

Two children developed profound visual loss in the eye being patched full time because of strabismic amblyopia in the fellow eye. The first had been patched for 13 days at age 18 months. Complete resolution was noted on the 40th day of reverse occlusion. The second had been patched for 1 month at age 9 months. After 3 months without treatment, reverse occlusion was instituted and was continued for 3 years. Mild amblyopia persists in both eyes of the second child. Although rare, occlusion amblyopia can occur in young children being patched full time. We usually avoid full-time occlusion and monitor patients at intervals at least as frequent as 1 week per year of age.

Congenital esotropia

Congenital esotropia represents the most common type of strabismus. Its pathogenesis, however, remains uncertain. It is typically characterized as a large angle, constant esotropia with onset during the first six months of life. Associated clinical findings include normal refractive errors for age, amblyopia, dissociated vertical deviation, inferior oblique muscle overaction and nystagmus. It must be distinguished from Duane's retraction syndrome, Moebius syndrome, nystagmus blockage syndrome, and early onset accommodative esotropia, as well as other causes of esotropia in infancy. The surgical management may involve recession of both medial recti muscles, unilateral recession of a medial rectus muscle and a resection of a lateral rectus muscle or three or four muscle surgery.

Surgical management of large angle congenital esotropia

Ninety-seven patients with congenital esotropia with deviations of 50 prism dioptres or greater underwent large (6 and 7 mm) bimedial rectus recessions. The overall success rate with one operation was 83.5%. Judgment of final alignment was made at the last follow-up examination, six to 61 months (average 23.4 months) postoperatively. Large bimedial rectus recessions for congenital esotropia are an effective surgical treatment which does not significantly alter adduction.

Preferential looking as a guide for amblyopia therapy in monocular infantile cataracts

Despite recent advances in surgical technique and refractive correction, amblyopia remains a significant problem in the treatment of monocular infantile cataracts. Amblyopia therapy recommended by different authors during the preverbal period has varied from no patching to nearly full-time occlusion of the phakic eye. We measured preferential looking (PL) acuities sequentially in four infants following monocular cataract surgery and contact lens correction. This information was used to adjust occlusion of the phakic eye, which was prescribed 25%-100% of waking hours. Patching schedules were altered, on average, every three to four months in response to changes in PL acuities. Four increases in patching intensity retarded acuity development in the phakic and benefited development in the aphakic eyes. Nine decreases enhanced progress or yielded no change in the phakic and, with two exceptions, impeded progress in the aphakic eyes. Recognition acuities now available for two of the children show continuity with previous PL acuities and confirm useful vision in the aphakic eyes. We describe guidelines for adjusting occlusion based on our experience. We believe that PL modulation of patching therapy may result in more favorable visual outcomes for both eyes of infants with monocular cataracts.

Spontaneous resolution of herpes simplex blepharoconjunctivitis in children

We observed three children, aged 1 year 8 months to 9 years 7 months, in whom herpes simplex blepharoconjunctivitis resolved promptly without treatment. A fourth child, 8 years old, developed probable toxic manifestations from topical vidarabine. These manifestations, as well as the blepharoconjunctivitis, resolved when the medication was discontinued. Herpes simplex ocular infection without corneal involvement in children is usually benign and self-limited.

Heat illness. A report of 45 cases from Hong Kong

During the summer of 1985, 45 soldiers with heat illness were admitted to the British Military Hospital, Hong Kong. Twelve had severe heat stroke, the remainder heat exhaustion. This paper discusses the management and prevention of heat illness in the military context.

Functional visual loss in children

Twenty-three children (16 girls, 7 boys, aged 6-17 years) who presented with the specific complaint of blurred vision were diagnosed as having functional visual loss. Symptoms were intermittent in seven children. Associated signs and symptoms were common and included headaches, visual field loss, diplopia, micropsia, voluntary nystagmus, and spasm of the near reflex. Our treatment consisted of reassurance and follow-up. Resolution of symptoms occurred within 24 hours in one third and within two months in three-quarters of our patients. Parental support and encouragement were associated with more rapid resolution. Recurrence of symptoms and late onset of somatic complaints were rare. Conflicts related to family or school environment were common. Four children had been sexually or physically abused. Our experience suggests that, regardless of the duration or severity of symptoms, functional visual loss in children can usually be treated with reassurance. We believe that psychiatric referral is not necessary for most patients. Sexual or physical abuse should be considered as a possible predisposing factor.

Posttraumatic convergence insufficiency

Convergence insufficiency was encountered following closed head trauma in 23 patients. The most common complaints included difficulty reading and diplopia at near. The severity of the head trauma varied. There was no correlation between the severity of the head trauma and the severity of the convergence insufficiency. A normal near point of convergence was encountered in six of the 23 patients; all six patients had abnormal convergence reserves when measured with prisms. Treatment consisted primarily of convergence exercises and prisms. Bilateral medial rectus resections were required in two patients. Response to therapy was variable and often incomplete. The anatomic localization of convergence insufficiency secondary to head trauma remains unknown, although lesions in the occipital lobe and upper midbrain both seem capable of producing this syndrome.

Athetosis in typhoid fever

A case of typhoid fever with neuropsychiatric features is described. These comprised confusion and delirium, meningism, a single major convulsion and bilateral athetoic movements. Athetosis has not previously been described in typhoid fever and must now be added to the long list of neuropsychiatric manifestations of this disease.

Failure of malaria chemoprophylaxis with a proguanil-chloroquine combination in Papua New Guinea

Proguanil 200 mg daily and chloroquine base 300 mg weekly were used as prophylaxis for 120 British Army soldiers from Hong Kong on a seven-week jungle exercise in the highly malarious Sepik district of Papua New Guinea. Compliance was rigidly enforced. Four men developed falciparum malaria whilst in Papua New Guinea and one within a few days of returning to Hong Kong. After stopping chloroquine four weeks after returning to Hong Kong 11 cases of mixed vivax and falciparum malaria and three cases of falciparum alone occurred within a 16-week period. This proguanil-chloroquine combination allows an unacceptably high level of breakthrough malaria and cannot be recommended for visitors to the highly malarious areas of Papua New Guinea.

Prosthetic treatment of severe microphthalmos in infancy

Four infants with blind, severely microphthalmic eyes have been treated with cosmetic scleral shells. Through periodic refitting, this method has permitted the development of symmetrical ocular appearance without the need for surgery. We recommend that this treatment be initiated in early infancy in appropriate patients.

Further observations on the first documented outbreak of trichinosis in Hong Kong

The first documented report of human trichinosis in Hong Kong is described comprising an outbreak amongst 20 Gurkha soldiers following a barbecue. The cardinal clinical features were fever, myalgia and facial oedema and the most useful laboratory tests were eosinophilia and elevated levels of creatinine phosphokinase. Gastrointestinal symptoms were uncommon. Seven patients who developed electrocardiographic abnormalities are the subject of an ongoing study. Four patients had psychiatric manifestations. Splinter haemorrhages, hypocalcaemia and evidence of renal dysfunction were absent. The parasite was recovered from 13 of patients and the diagnosis confirmed serologically in all. The value of the enzyme-linked immunosorbent assay (ELISA) for IgM and IgE antibodies is emphasized in that it is 100% specific and sensitive. Thiabendazole alone was used in treatment and all patients recovered.

Familial simple ectopia lentis: a case study

Hereditary simple ectopia lentis affected nine patients in three generations of a family. Inheritance appeared to be autosomal dominant. Examination of 12 family members, employing body proportion measurements, chest x-ray, echocardiogram, and urinary cystine or blood methionine levels, revealed no evidence of any systemic disease. In all cases except two, lenses were bilaterally and superiorly dislocated. The degree of dislocation varied considerably among those affected, causing no visual disturbance in some and severely limiting visual acuity in others. Visual deficits were greatest in patients with intermediate degrees of dislocation. To date, the only known complications related to the dislocations have been two cases of bilateral cataracts. The indications for lensectomy in patients with ectopia lentis are reviewed.

A simple grating visual acuity test for impaired children

Twenty-five developmentally delayed or neurologically impaired nonverbal children, aged 2 to 15 years, referred for visual acuity assessment, were beyond the age at which standard preferential-looking techniques are considered to be effective and none could be tested with Snellen letters, illiterate Es, or Allen pictures. Our method, in which the children learn to point to grating stimuli, enabled us to obtain monocular visual acuity estimates in 19 of the 25 patients. When indicated, patching therapy was begun and was monitored with this method. Similar testing of 31 unimpaired children showed good prediction of recognition visual acuities except in patients with visual acuities worse than 20/160. The grating method accurately identified or excluded amblyopia in 26 of 31 children (84%). We consider this a clinically useful test of visual acuity in nonverbal impaired children.

Tick borne relapsing fever imported into the United Kingdom

A case of tick borne relapsing fever contracted in Cyprus and imported into England is reported. This is the first report of the diagnosis being established by finding the organism in the bone marrow.

Reflux and voiding abnormalities in children

Twenty-four patients with vesicoureteral reflux were studied urodynamically because of a history of dysfunctional voiding. Nine patients eventually had antireflux surgery. The remaining 15 patients were followed from two to six years. These patients were managed conservatively with an emphasis on controlling infection and improving voiding habits. Reflux resolved spontaneously in 12 patients and improved in 1 patient. Dysfunctional voiding is a definite cause of childhood reflux. Treatment should be directed at improving voiding patterns. Coordinated voiding may allow a child to "grow out" of his reflux.

Anterior segment ischemia following strabismus surgery

Anterior segment ischemia (ASI) is a potentially blinding complication of extensive eye muscle surgery. Eyes have been described with this complication following surgery on as few as two rectus muscles, especially in patients with thyroid dysfunction or other medical illnesses. In an attempt to assess the risk of ASI, we have reviewed the records of 34 eyes in 26 patients who underwent surgery on three or four rectus muscles. Seven eyes of six patients with thyroid ophthalmopathy which underwent two-or three-muscle surgery were also studied. Evidence of clinically significant ASI was apparent in only one patient during a follow-up period of seven months to eleven years. This case was mild and no visual loss resulted. Our findings suggest that surgery on three or four rectus muscles in healthy patients is probably safe when performed in a staged fashion.