National outcomes of cataract extraction. I. Retinal detachment after inpatient surgery.

Rehospitalization for retinal detachment (RD) was studied in 338,141 Medicare beneficiaries older than 65 years of age who were undergoing inpatient cataract extraction in 1984. Extracapsular cataract extraction (ECCE) was performed in 60% of patients, intracapsular cataract extraction (ICCE) in 31%, and phacoemulsification in 9%. The risk of rehospitalization for RD within 4 years of ICCE was 1.

Risk of cataract and history of severe diarrheal disease in southern India.

A case-control study was carried out in the state of Tamil Nadu, southern India, to examine the association between the risk of visually disabling cataract and a lifetime history of severe diarrhea (including cholera). A series of 421 subjects, aged 35 to 65 years, meeting case (n = 181) and control (n = 240) eligibility criteria were enrolled from 19 rural cataract-screening camps. Ninety case-control pairs were postmatched for (reported) age (+/- 2 years), sex, and area of residence.

Visual parameters in patients with pituitary adenoma before and after transsphenoidal surgery.

Eighty-two patients with pituitary adenoma who underwent transsphenoidal surgery were examined before and after surgery. Nineteen patients had a normal preoperative neuro-ophthalmological examination. All of these patients maintained normal visual parameters postoperatively.

Displacement of the optic nerve head by acute changes in intraocular pressure in monkey eyes.

The authors used the Humphrey Retinal Analyzer to study the effect of acute changes in intraocular pressure (IOP) on the topography of the optic nerve head in normotensive and hypertensive eyes of cynomolgus monkeys. Chronically elevated IOP was produced monocularly in monkeys by argon laser angle treatment. In 8 hypertensive eyes, the mean IOP of 51 mmHg was lowered acutely to 15 mmHg with a needle placed in the anterior chamber.

Long-term survival rate after vitreous surgery for complications of diabetic retinopathy.

The survival rate after vitreous surgery for complications of diabetic retinopathy was studied in 552 consecutive patients who underwent operations between 1979 and 1984. The 5-year postoperative survival rate was 74.7%.

[Snoring: an epidemiological study on 1146 adult subjects].

An epidemiological survey of the prevalence of snoring was performed on 1146 adults consecutively observed in the offices of several practitioners. A reliable, previously assessed snoring questionnaire was given to all patients. Snoring was found as a common sign as 31% of the subjects referred to this symptom.

The relationship of puberty to diabetic retinopathy.

The presence of background and preproliferative retinopathy in 70 patients with type I diabetes was correlated with their pubertal development. Pubertal status was assessed by pediatricians using the sexual maturity ratings of Tanner. In young diabetics with comparable disease duration (5 to 10 years), postpubertal children had a greater prevalence of retinopathy than those who were not sexually mature.

Miosis during vitreoretinal surgery.

Maintenance of wide pupillary dilation during vitreoretinal surgery can be important in successful completion of the operation. This study identified factors associated with intraoperative miosis. Also, flurbiprofen, a topically applied nonsteroidal anti-inflammatory agent, was evaluated for its efficacy in preventing intraoperative miosis in a prospective, randomized study of 99 consecutive patients.

Spin equilibria in human methemoglobin: effects of bezafibrate and inositol hexaphosphate as measured by susceptometry and visible spectroscopy.

The effects of inositol hexaphosphate (IHP) and a second allosteric effector, bezafibrate, on the spin-state equilibria of the mixed-spin derivatives of ferric human hemoglobin A are examined. Changes in spin-state equilibrium are monitored by measuring absorption spectra in the visible region (460-700 nm) as well as by direct measurements of magnetic susceptibility by means of a superconducting fluxmeter. The addition of IHP at pH 6.

Leukemic retinopathy. Relationship between fundus lesions and hematologic parameters at diagnosis.

The authors examined 117 consecutive patients with acute leukemia within a few days of diagnosis. Sixty-six patients had acute nonlymphocytic leukemia, and 51 had acute lymphocytic leukemia. Forty-two percent of the patients had abnormal ocular findings related to leukemia.

Studies on the linkage between spin equilibria and protein structure in carp ferric hemoglobin.

The effects of protein conformation on the spin-state equilibria of several derivatives of carp hemoglobin have been examined. This has been done by measuring the pH dependence of the paramagnetic susceptibilities of these derivatives in the presence and absence of inositol hexakisphosphate, P6-inositol. In all cases the addition of P6-inositol at low pH and the lowering of the pH in the presence of P6-inositol shift the spin-state equilibrium in favor of the high-spin electronic configuration.

Reexamination of the evidence for paramagnetism in oxy- and carbonmonoxyhemoglobins.

Experiments have been carried out in an attempt to confirm previous reports of paramagnetism in the oxy- and carbonmonoxy derivatives of human and carp hemoglobin. When care is taken to ensure complete saturation of the hemoglobins with ligand and the diamagnetic contributions of all of the buffers are carefully evaluated, these hemoglobin derivatives are found to have the same gram susceptibilities as exhibited by a set of metal free proteins, suggesting that they are fully diamagnetic.

Quaternary structure and spin equilibria in ferric hemoglobins. A room temperature study.

The effective magnetic moments for a number of human and carp methemoglobin derivatives were determined in solution at room temperature. The data permit us to confirm the dependence of the spin-state equilibrium of azide methemoglobin on the quarternary state of the hemoglobin and to demonstrate a similar dependence for both human and carp aquomethemoglobin. In addition, the pH dependence of the effective magnetic moment and the Soret spectrum of carp azidemethemoglobin are compared.

Magnetic and spectral properties of carp carbonmonoxyhemoglobin. Competitive effects of chloride ions and inositol hexakisphosphate.

We have extended our studies on the magnetic properties of carp carbonmonoxyhemoglobin and the dependence of these properties upon solution variables. Using an improved version of the superconducting magnetometer, we have found that the magnetic susceptibility of carp carbonmonoxyhemoglobin is sensitive to both inositol hexakisphosphate and chloride ion. The dependence upon chloride ion concentration is complex.

Magnetic equivalence of the hemes in hemoglobin Zürich.

The magnetic susceptibilities of solutions of deoxyhemoglobin Zürich and deoxyhemoglobin A have been found quite close together, in contrast to previous findings. Therefore, any magnetic inequivalence between alpha- and beta-hemes must be confined to finer details.

Variability of the magnetic moment of carbon monoxide hemoglobin from carp.

Deionized carp carbon monoxide hemoglobin in distilled water or in bis(2-hydroxyethyl)imino-tris(hydroxymethyl)methane or Tris buffer exhibits a slight but significant paramagnetism. This is most clearly demonstrated by the decrease in this paramagnetism that is caused by the addition of inositol hexaphosphate to this protein in the former buffer at pH 6.3-6.

Room-temperature magnetic properties of oxy- and carbonmonoxyhemoglobin.

The magnetic susceptibility and the density of human oxy-(HbO(2)) and carbonmonoxyhemoglobin (HbCO) solutions of various concentrations have been measured at room temperature, with pure water used as a calibrant. Solutions of unstripped and stripped HbO(2) at pH 7.2 in unbuffered water solvent were always found to be less diamagnetic than pure water, whereas solutions of HbCO in identical conditions were always found to be more diamagnetic than pure water.

Magnetic properties of oxyhemoglobin.

When the magnetic susceptibility of frozen aqueous solutions of human oxyhemoglobin was measured in the range between 25 and 250 K, it showed a temperature-dependent behavior typical of a thermal equilibrium between a ground singlet state and an excited triplet state for two electrons per heme, the energy separation being [2J] = 146 cm-1. By contrast, within the same temperature range, carboxyhemoglobin was found to be diamagnetic, as already reported.