Essential fatty acid deficiency in total parenteral nutrition. Detection by changes in intraocular pressure

Essential fatty acid deficiency (EFAD) has been commonly and readily diagnosed during fat-free total parenteral nutrition (TPN), with only vague awareness of possible functional and clinical derangements secondary to essential fatty acid deficiency. Arachidonic acid is known to be a precursor for prostaglandin (PG) synthesis. Prostaglandins are known to be intermediaries between stimulus and cellular response in a variety of physiologic and pathologic processes; one would suspect therefore that EFAD would result in PG deficiency with resultant multiple derangements in functions regulated by PG. We tested this hypothesis by serially measuring intraocular pressure (IOP) in patients before and during fat-free TPN and after supplementing these patients with fat. In the eye as well as in various other organs PG are believed to act as mediators of adrenergic neurotransmission by a negative feedback mechanism. As catecholamines are potent ocular hypotensive agents, decreased levels of PG due to EFAD will cause increase in catecholamine turnover with a reduction in IOP. Two groups of patients matched as to their age, sex, nutritional status and diseases were studied. One group (control) was receiving a normal diet or fat-containing TPN while the other group was receiving fat-free TPN. IOP in the fat-free TPN group dropped from 13.7 +/- 0.4 mmHg pre-TPN to 9.3 +/- 0.5 mmHg during the first week of fat-free TPN. Within two weeks after supplementation of fat or return to normal oral diet IOP returned to 13.9 +/- 0.3 mmHg. Prostaglandin levels, which were 0.025 +/- 0.004 ng/ml pre-TPN or in control patients decreased to 0.012 +/- 0.002 ng/ml (p < 0.001) during fat-free TPN, to return to normal after fat was added to TPN regime or patients returned to normal oral diet. During fat-free TPN linoleic acid levels decreased to 40% of its initial value with a mild increase upon the addition of fat, while eicosatrienoic acid and the triene:tetraene ratio increased to 6.5 times their initial values. Arachidonic acid levels did not change during fat-free TPN or after repletion with fat. Intraocular pressure determination seem to be a simple, harmless, inexpensive, reliable and sensitive indicator of EFAD. Moreover, IOP determination represent a functional derangement which in a clinical setting lends functional credence to the biochemical changes of EFAD whose entire significance has not yet been determined. Similarly, serial IOP determinations are sensitive in detecting adequate functional repletion of EFAD. As PG are known to act as intermediaries in a variety of physiological processes it seems reasonable to assume that the change in IOP is only one of many different changes and derangements to occur as a result of PG and EFA deficiency.

The additive effect of timolol on open angle glaucoma patients on maximal medical therapy

Thirty-one eyes of 20 glaucomatous patients on maximum medication were treated with timolol drops for a mean period of 9 months. Adequate levels of control of intraocular pressures were obtained in 21 eyes. No significant ocular or systemic side effects were noted. Timolol has an additive effect in further lowering intraocular pressures in patients being treated with a combination of carbonic anhydrase inhibitors, pilocarpine, epinephrine, and the anticholinesterases.

Structure of Guinea Pig Ia Antigens

Guinea pig Ia molecules bearing the markers 3, 5 and 7 (strain 13) and 4, 5 (strain 2) were isolated from spleen and lymph node cells. In the molecules bearing the 7 and the 4, 5 markers, the 25,000 and 33,000 MW polypeptide chains are linked by disulfide bonds. The molecules bearing the 3, 5 markers do not have polypeptide chains linked by disulfide bonds. These glycoproteins were metabolically labeled with tritiated amino acids and purified by NP-40 lysis, affinity chromatography on columns of lentil lectin and specific immunoabsorbents, followed by SDS-PAGE. In some cases the immunoabsorbent chromatography was replaced by immunoprecipitation using SaCI. The radioactive polypeptide chains were eluted from the gel and characterized by peptide mapping and by sequence analysis of the N-terminal regions of the 25,000 MW chains. The preliminary results indicate that all three 25,000 MW chains studied were homologous.

Inflammatory response of guinea pig to injected limbal tissue

This study examined the possibility that homologous limbal tissue, including trabecular meshwork, serving as an antigen, could elicit inflammatory cells responsible for both aqueous obstruction and inflammation; the possible role of this response in ocular disease was also studied. Four sets of guinea pigs were sensitized with complete Freund's adjuvant. One set received just adjuvant and saline, one set received adjuvant plus uvea, and two sets received adjuvant plus limbal tissue. The animal injected with only adjuvant and saline all showed normal ocular histology. Sensitizing guinea pigs with limbus and adjuvant produced mononuclear infiltration of the uvea, trabeculum, and episclera. Lymphocytes and plasma cells predominated. The response induced by the limbus seemed to consist of two components: a uveal and a specific limbal component. The lymphoid infiltration of the uvea was identical to the response induced by uveal antigen in our uvea control group. The limbal component was characterized by clusters of lymphocytes and plasma cells in the trabecular and episcleral regions. This study showed that limbal tissue antigen induces an inflammatory response in both uvea and limbus, and that the inflammatory response in the trabeculum is greater with limbal than uveal antigen.

[The idiopathic paroxysmal myoglobinuric myopathy (Meyer-Betz) (author's transl)]

The idiopathic paroxysmal myoglobinuric myopathy (IPMM) as a genuine disease can be differentiated from other myoglobinurias by clinical criterias. Concerning the course of the disease two different types of IPMM are to be seen, sporadic cases are observed as well as familiar, autosomal recessive inherited ones. Regarding the pathogeny of IPMM several metabolic disorders are discussed: Provocation of the disease by physical exertion and glucose deficiency point to a disturbance of carbohydrate metabolism. Disorders of lipid metabolism are reported, too. So we tried to analyse the results of a case study in relation to the presently discussed - still hypothetical - pathogenetic ideas. Our laboratory, histological and electromyographic findings suggest a primary myopathy, which might be based on a peripheral glucose utilisation disorder (ATP-deficiency). Under the condition of exertion this disorder leads to a decompensation of the muscular functional and structural metabolism manifested by an excessive efflux of myoglobin and enzymes.

Specificity of fluorescein angiographic defects of the optic disc in glaucoma

Fluorescein angiography of the optic disc was performed on normal subjects, patients with nonmyopic open-angle glaucoma dna myopic open-angle glaucoma, normal myopes, patients with optic atrophy due to chiasmal pituitary tumors, and patients with sectorial ischemic optic neuropathy due to vascular hypotension. The normal myopes, those with optic atrophy secondary to pituitary tumor, and the ischemic optic neuropathy group had optic discs similar in appearance to those with open-angle glaucoma. Absolute fluorescein filling defects occurred only in patients with open-angle glaucoma and sectorial ischemic optic neuropathy. The filling defects in open-angle glaucoma appear to be specific, indicating that the blood supply to the anterior portion of the optic nerve is involved, as in ischemic optic neuropathy. Fluorescein angiography of the optic disc may be useful to differentiate open-angle glaucoma from other entities that have similar optic discs.

Scanning microdensitometry of optic disc pallor in glaucoma

A scanning microdensitometric technique has been developed for measuring the optical density of black and white photographs of the optic disc. From the frequency distribution curve of all the densities of the whole area of the optic disc, a separate peak was identified as corresponding to the area of pallor of the optic disc. Areas of pallor were measured as percentage of areas of the total disc for normal, ocular hypertensive, open-angle glaucoma patients, and those with suspect discs. Median values of percent area of pallor showed correspondence with the clinical diagnosis, the glaucoma patients having significantly larger areas than the normal subjects. The microdensitometric technique provides an objective means of measuring the amount of optic dis pallor. It has potential usefulness for screening and for following up suspect and confirmed glaucomas to determine progression of the disease.

Fluorescein angiographic defects of the optic disc in glaucoma

An improved technique for high-contast, high-resolution fluorescein angiography of the optic disc has been developed that almost eliminates pseudofluorescence. Fluorescein angiography of the optic disc was performed on normal, ocular hypertensive, and glaucomatous patients. Rapid-sequence angiograms in the early arterial phases have demonstrated localized areas of hypofluorescence or filling defects of the optic disc. Two types of fluorescein filling defects were observed-absolute and relative. The number of absolute filling defects, which increased with degree of visual field loss, was greater in glaucomatous than in ocular hypertensive or normal eyes. Similarly, ocular hypertensive eyes showed a larger number of discs with filling defects than normal eyes. It is postulated that relative defects progress to absolute filling defects, which may be an indication of impending loss of visual field.

Fluorescein angiographic defects of the optic disc in ocular hypertension

Fluorescein angiograms of the optic disc were studied in 23 normal and 29 ocular hypertensive eyes. Significant differences in the frequency distributions of areas of defects were obtained between normal and ocular hypertensive eyes. Increased areas of filling defects were noted in ocular hypertensive eyes as compared to normals. There were also significant correlations of the areas of filling defects with age and systolic blood pressure in the ocular hypertensive eyes that were not present in the normals. These observations support the concept that fluorescein angiography of the optic disc demonstrates localized areas of impaired circulation that increase with ocular pressure, age, and systolic blood pressure. This technique may be useful in separating normal from the ocular hypertensive patient who shows changes in the circulation of the optic disc with increased ocular pressure.

Optic disc in glaucoma: Topography and extent of fluorescein filling defects

The topography and extent of localized areas of hypofluorescence or absolute filling defects of the optic discs of glaucomatous patients correlated positively with the loss of visual field. Filling defects tended to cluster at the inferior and superior poles of the optic disc and were closer to the disc margin than to the center. The location of the defects corresponded with the expected site of visual field loss. There was a positive correlation between the percent area of the filling defects and the degree of visual field loss. These observations support the concept that fluorescein filling defects of the optic disc in glaucoma represent areas of ischemia that are highly correlated with loss of visual field.

Dermal patch urethroplasty: experimental and clinical experience

Our experience with a dermal patch graft urethroplasty is presented in 10 Pitman-Moore minipigs. Histologic review at various post-urethroplasty intervals showed epithelialization of the graft. In addition, several cases in which this technique was used are presented with early followup. The advantages of dermal patch urethroplasty as well as the application of dermal grafts in other areas of the urinary tract are discussed.

Cold agglutinins in infectious mononucleosis and heterophil-antibody-negative mononucleosis-like syndromes

Cold agglutinins (CA) were evaluated prospectively in patients with various mononucleosis syndromes and in a large control group. Cold agglutinins with anti-i specificity were seen mainly in heterophil-positive or -negative Epstein-Barr virus (EBV)-induced infectious mononucleosis (31.8% of cases). Unclassified CA with equal reactivity against cord and adult erythrocytes were seen in 56 of 150 (37.3%) cases of heterophil-antibody-positive infectious mononucleosis (IM), in 1 of 7 (14.3%) cases of heterophil-negative EBV-induced IM, and in 12 of 31 (38.7%) cases of the heterophil-negative mononucleosis-like syndrome due to cytomegalovirus or other unspecified agents. One patient with heterophil-positive IM had a persistent, partially papain sensitive CA with anti-Pr-like activity. Anti-i CA were seen in less than 1.0% of healthy young adults (500) or patients without mononucleosis (500) submitted for heterophil studies. Unclassified CA were noted in 3.2% of the latter 1000 samples.

Stable Semiconductor Liquid Junction Cell with 9 Percent Solar-to-Electrical Conversion Efficiency

The semiconductor liquid junction cell n-GaAs/0.8M K(2)Se-0.1M K(2)Se(2)-1M KOH/C has been shown to attain 9 percent photovoltaic power conversion efficiency in sunlight. Accelerated tests under 3100 degrees K light sources of several solar intensities indicate very low photocorrosion currents and high output stability.

Calculated neutron dose rates and flux densities from implantable californium-252 point and line sources

The results of neutron-transport flux-density and dose rate calculations for implantable Californium-252 point and line sources in essentially infinite tissue-equivalent material are presented. The point-source flux densities were obtained from a discrete ordinates calculation, and the point dose rates were established by multiplying the flux densities by their appropriate kerma factors. Line-source dose rates were evaluated by integrating the point dose rates over the length of the line source. Dose-rate data are given within a 20 X 20-cm region from the source center for source lengths of 1.5, 2, and 3 cm. The dose rates established by these calculations showed good agreement with an independent Monte Carlo calculation. Detailed point-source flux-density data as a function of energy and position are also given.