Comparison of Molly and Karoline models to predict methane production in growing and dairy cattle.

Numerous empirical and mechanistic models predicting methane (CH4) production are available. The aim of this work was to evaluate the Molly cow model and the Nordic cow model Karoline in predicting CH4 production in cattle using a data set consisting of 267 treatment means from 55 respiration chamber studies. The dietary and animal characteristics used for the model evaluation represent the range of diets fed to dairy and growing cattle. Feedlot diets and diets containing additives mitigating CH4 production were not included in the data set. The relationships between observed and predicted CH4 (pCH4) were assessed by regression analysis using fixed and mixed model analysis. Residual analysis was conducted to evaluate which dietary factors were related to prediction errors. The fixed model analysis showed that the Molly predictions were related to the observed data (± standard error) as CH4 (g/d) = 0.94 (±0.022) × pCH4 (g/d) + 31 (±6.9) [root mean squared prediction error (RMSPE) = 45.0 g/d (14.9% of observed mean), concordance correlation coefficient (CCC) = 0.925]. The corresponding equation for the Karoline model was CH4 (g/d) = CH4 (g/d) = 0.98 (±0.019) × pCH4 (g/d) + 7.0 (±6.0) [RMSPE = 35.0 g/d (11.6%), CCC = 0.953]. Proportions of mean squared prediction error attributable to mean and linear bias and random error were 10.6, 2.2, and 87.2% for the Molly model, and 1.3, 0.3, and 98.6% for the Karoline model, respectively. Mean and linear bias were significant for the Molly model but not for the Karoline model. With the mixed model regression analysis RMSPE adjusted for random study effects were 10.9 and 7.9% for the Molly model and the Karoline model, respectively. The residuals of CH4 predictions were more strongly related to factors associated with CH4 production (feeding level, digestibility, fat concentrations) with the Molly model compared with the Karoline model. Especially large mean (underprediction) and linear bias (overprediction of low digestibility diets relative to high digestibility diets) contributed to the prediction error of CH4 yield with the Molly model. It was concluded that both models could be used for prediction of CH4 production in cattle, but Karoline was more accurate and precise based on smaller RMSPE, mean bias, and slope bias, and greater CCC. The importance of accurate input data of key variables affecting diet digestibility is emphasized.

Adipose tissue insulin receptor and glucose transporter 4 expression, and blood glucose and insulin responses during glucose tolerance tests in transition Holstein cows with different body condition.

Glucose uptake in tissues is mediated by insulin receptor (INSR) and glucose transporter 4 (GLUT4). The aim of this study was to examine the effect of body condition during the dry period on adipose tissue mRNA and protein expression of INSR and GLUT4, and on the dynamics of glucose and insulin following the i.v. glucose tolerance test in Holstein cows 21 d before (d -21) and after (d 21) calving. Cows were grouped as body condition score (BCS) ≤3.0 (thin, T; n = 14), BCS = 3.25 to 3.5 (optimal, O; n = 14), and BCS ≥3.75 (overconditioned, OC; n = 14). Blood was analyzed for glucose, insulin, fatty acids, and ß-hydroxybutyrate concentrations. Adipose tissue was analyzed for INSR and GLUT4 mRNA and protein concentrations. During the glucose tolerance test 0.15 g/kg of body weight glucose was infused; blood was collected at -5, 5, 10, 20, 30, 40, 50, and 60 min, and analyzed for glucose and insulin. On d -21 the area under the curve (AUC) of glucose was smallest in group T (1,512 ± 33.9 mg/dL × min) and largest in group OC (1,783 ± 33.9 mg/dL × min), and different between all groups. Basal insulin on d -21 was lowest in group T (13.9 ± 2.32 µU/mL), which was different from group OC (24.9 ± 2.32 µU/mL. On d -21 the smallest AUC 5-60 of insulin in group T (5,308 ± 1,214 µU/mL × min) differed from the largest AUC in group OC (10,867 ± 1,215 µU/mL × min). Time to reach basal concentration of insulin in group OC (113 ± 14.1 min) was longer compared with group T (45 ± 14.1). The INSR mRNA abundance on d 21 was higher compared with d -21 in groups T (d -21: 3.3 ± 0.44; d 21: 5.9 ± 0.44) and O (d -21: 3.7 ± 0.45; d 21: 4.7 ± 0.45). The extent of INSR protein expression on d -21 was highest in group T (7.3 ± 0.74 ng/mL), differing from group O (4.6 ± 0.73 ng/mL), which had the lowest expression. The amount of GLUT4 protein on d -21 was lowest in group OC (1.2 ± 0.14 ng/mL), different from group O (1.8 ± 0.14 ng/mL), which had the highest amount, and from group T (1.5 ± 0.14 ng/mL). From d -21 to 21, a decrease occurred in the GLUT4 protein levels in both groups T (d -21: 1.5 ± 0.14 ng/mL; d 21: 0.8 ± 0.14 ng/mL) and O (d -21: 1.8 ± 0.14 ng/mL; d 21: 0.8 ± 0.14 ng/mL). These results demonstrate that in obese cows adipose tissue insulin resistance develops prepartum and is related to reduced GLUT4 protein synthesis. Regarding glucose metabolism, body condition did not affect adipose tissue insulin resistance postpartum.

Transforming growth factor-beta 1: histochemical localization with antibodies to different epitopes.

We have localized transforming growth factor-beta (TGF-beta) in many cells and tissues with immunohistochemical methods, using two polyclonal antisera raised to different synthetic preparations of a peptide corresponding to the amino-terminal 30 amino acids of TGF-beta 1. These two antibodies give distinct staining patterns; the staining by anti-CC(1-30) is intracellular. This differential staining pattern is consistently observed in several systems, including cultured tumor cells; mouse embryonic, neonatal, and adult tissues; bovine fibropapillomas; and human colon carcinomas. The extracellular staining by anti-CC(1-30) partially resembles that seen with an antibody to fibronectin, suggesting that extracellular TGF-beta may be bound to matrix proteins. The intracellular staining by anti-LC(1-30) is similar to that seen with two other antibodies raised to peptides corresponding to either amino acids 266-278 of the TGF-beta 1 precursor sequence or to amino acids 50-75 of mature TGF-beta 1, suggesting that anti-LC(1-30) stains sites of TGF-beta synthesis. Results from RIA and ELISAs indicate that anti-LC(1-30) and anti-CC(1-30) recognize different epitopes of this peptide and of TGF-beta 1 itself.

Unrecognized diabetes among hospitalized patients.

OBJECTIVE: To evaluate the hospital care rendered to hyperglycemic individuals who did not have a diagnosis of diabetes before admission. RESEARCH DESIGN AND METHODS: A total of 1,034 consecutively hospitalized adult patients at a 750-bed inner-city teaching hospital were evaluated. Patients with one or more plasma glucose values > 200 mg/dl were identified by the laboratory data system on a daily basis. Patients without a diagnosis of diabetes at the time of admission were evaluated to determine if and how physicians addressed the hyperglycemia, whether a new diagnosis of diabetes was made during admission, and whether follow-up was planned to address the hyperglycemia. RESULTS: After excluding patients who were admitted for a primary diagnosis of diabetes, 37.5% of all hyperglycemic medical patients and 33% of hyperglycemic surgical patients were without a diagnosis of diabetes at the time of admission. These patients had a mean peak glucose of 299 mg/dl, and 66% had two or more elevated values during their hospitalization. Fifty-four percent received insulin therapy, and 59% received bedside glucose monitoring, yet 66% of daily patient progress notes failed to comment on the presence of hyperglycemia or diabetes. Diabetes was documented in only three patients (7.3%) as a possible diagnosis in the daily progress notes. CONCLUSIONS: Despite marked hyperglycemia, most medical records made no reference to the possibility of unrecognized diabetes. Given the average delay of a decade between the onset and diagnosis of type 2 diabetes, further evaluation of hyperglycemic hospitalized patients may present an important opportunity for earlier detection and the initiation of therapy.

Partial PFO Closure for Persistent Hypoxemia in a Patient with Ebstein Anomaly.

Ebstein anomaly is characterized by deformities of the anterior leaflet of the tricuspid valve and atrialization of the right ventricle. Patients with severe tricuspid regurgitation are recommended to have tricuspid valve surgery with concomitant atrial septal defect closure. A 73-year-old female with Ebstein anomaly presented with severe hypoxemia. Transthoracic echocardiography revealed severe tricuspid regurgitation and a patent foramen ovale with right-to-left shunting. Complete percutaneous patent foramen ovale closure led to acute decompensation; however, partial closure led to hemodynamic stability and improved oxygenation. In conclusion, similar patients with "patent foramen ovale dependency" from longstanding shunts may benefit from partial patent foramen ovale closure.

Disseminated peritoneal adenomucinosis and peritoneal mucinous carcinomatosis. A clinicopathologic analysis of 109 cases with emphasis on distinguishing pathologic features, site of origin, prognosis, and relationship to "pseudomyxoma peritonei".

Pseudomyxoma peritonei (PMP) is a poorly understood condition characterized by mucinous ascites and mucinous implants diffusely involving the peritoneal surfaces. There is considerable debate regarding the definition, pathology, site of origin, and prognosis of PMP. We analyzed the clinicopathologic features of 109 cases of multifocal peritoneal mucinous tumors to develop a pathologic definition of cases characterized by the clinical condition PMP. Cases were separated into two diagnostic categories: disseminated peritoneal adenomucinosis (DPAM) and peritoneal mucinous carcinomatosis (PMCA). Cases classified as DPAM were characterized by peritoneal lesions composed of abundant extracellular mucin containing scant simple to focally proliferative mucinous epithelium with little cytologic atypia or mitotic activity, with or without an associated appendiceal mucinous adenoma. Cases classified as PMCA were characterized by peritoneal lesions composed of more abundant mucinous epithelium with the architectural and cytologic features of carcinoma, with or without an associated primary mucinous adenocarcinoma. Sixty-five of the 109 cases (59.6%) were classified as DPAM consistent with origin from an appendiceal mucinous adenoma. Thirty-seven of the 65 cases (56.9%) had a documented appendiceal mucinous adenoma. Thirty cases (27.5%) were classified as PMCA consistent with origin from an appendiceal or intestinal mucinous adenocarcinoma. Fourteen cases (12.8%) were classified as PMCA with features intermediate between DPAM and PMCA or with discordant features based on the finding of at least focal areas of carcinoma in the peritoneal lesions, whether or not the primary site demonstrated carcinoma. The cases with intermediate features were derived from well-differentiated appendiceal or intestinal mucinous adenocarcinomas and had peritoneal lesions displaying features of DPAM as well as focal areas of mucinous carcinoma. The cases with discordant features were derived from atypical appendiceal adenomas with little or no histologic evidence of a transition from adenoma to carcinoma and had peritoneal lesions uniformly composed of mucinous carcinoma. There was a statistically significant difference in survival between cases classified as DPAM, those classified as PMCA with intermediate or discordant features, and those classified as PMCA (p < 0.0001). The age-adjusted 5-year survival rates were 84% for patients with DPAM, 37.6% for patients with PMCA with intermediate or discordant features, and 6.7% for patients with PMCA. The term DPAM should be used to diagnose the histologically benign peritoneal lesions associated with ruptured appendiceal mucinous adenomas and those that are pathologically identical but lack a demonstrable appendiceal adenoma. Cases with the pathologic features of adenocarcinoma should be designated PMCA because they have recognizably different pathologic features and a significantly worse prognosis.

Prostaglandin and thromboxane synthesis by microsomes of rabbit ocular tissues.

Microsomes of albino rabbit ocular tissues were incubated with (1-14C)-arachidonic acid for 15 min at 37 degrees C. Thin-layer chromatography revealed that ciliary body-iris microsomes were capable of synthesizing prostaglandin F2alpha (PGF2alpha), PGE2, PGD2, thromboxane B2(TXB2), and 6-keto-PGF1alpha. Indomethacin 14 micrometer in the incubation medium essentially abolished all prostaglandin synthesis detectable by this method. Imidazole 10 mM in the incubation medium inhibited only TXB2 synthesis. Ciliary body-iris microsomes were incubated for 2 min at 0 degrees C with PGH2. The products of this reaction were superfused over spiral strips of rabbit aorta and produced the strong contractions typical of TXA2. Addition to imidazole to the incubation medium blocked the formation of the contracting substance. Incubation of ciliary body-iris microsomes with (1-14C)--8,11,14-eicosatrienoic acid produced PGF1alpha, PGD1, and PGE1 but no evidence of any thromboxane product or 6-keto-PGF1alpha. Conjunctival and corneal microsomes synthesized prostaglandins, although less effectively than ciliary body-iris microsomes, when incubated with (1-14C)-arachidonic acid. Microsomes of sclera, retina-choroid, and lens synthesized little, if any, prostaglandins.

The ocular anti-inflammatory action of imidazole.

Imidazole administered intraperitoneally to albino rabbits at a dose of 250 mg. per kilogram inhibited the rise of aqueous humor protein concentration by approximately 50 per cent 30 minutes after paracentesis. Systemic imidazole administered daily to albino rabbits injected with intravitreal Shigella endotoxin decreased the conjunctival and iris hyperemia and reduced the anterior chamber cell and flare and the haziness of the optical media. Systemically administered imidazole had no effect on the aqueous humor concentrations of c-AMP or c-GMP in the rabbit. In vitro studies of rabbit ciliary body-iris phosphodiesterase activity indicated no effect of imidazole at a concentration of 10(-3) molar.

The ocular hypotensive effect of epinephrine in high and low corticosteroid responders.

Nonglaucomatous individuals were classified by their intraocular pressure response to 6 weeks of topical dexamethasone, 0.1%, four times daily. Twenty GG responders (over 31 mm. Hg after dexamethasone) and 20 NN responders (below 20 mm. Hg after dexamethasone) of similar age, sex, race, initial intraocular pressure, and facility of outflow were selected. After 24 hr. of treatment (two doses) with 1% epinephrine HCl, the GG subjects demonstrated a mean (+/-sigma) corrected decrease in intraocular pressure of 4.2 mm. Hg (+/- 2.5) as opposed to 1.8 mm. Hg (+/- 2.1) in the NN subjects (p less than 0.005). The relationship between increased responsiveness to corticosteroids, to epinephrine, and to theophylline suggested cyclic nucleotides as a possible common pathway.

Prostaglandin and thromboxane synthesis by microsomes of inflamed rabbit ciliary body--iris.

Microsomes of albino rabbit ciliary body--iris were prepared 6 hr, 24 hr, 3 days, 7 days, and 28 days after intravitreal injection of 10 micrograms of Shigella endotoxin. The microsomal preparations were incubated for 15 min with [1-14C]arachidonic acid. Prostaglandin and thromboxane products (cyclo-oxygenase products) were identified by thin-layer chromatography and quantified by scintillation counting. Synthesis of prostaglandin F2 alpha (PGF2, PGD2, 6-keto-PGF1 alpha (a stable metabolite of PGI2) and thromboxane B2 (TXB2) (a stable metabolite of TXA2) was increased 24 hr, 3 days, and 7 days after endotoxin injection. The greatest increase was in TXB2 synthesis. Cyclo-oxygenase product synthesis returned to normal levels by 28 days. Ciliary body--iris microsomes prepared 15 min after paracentesis synthesized increased amounts of all cyclo-oxygenase products assayed, most notably TXB2 and PGE2. Ciliary body--iris microsomes from albino rabbit treated with topical 1% nitrogen mustard or pigmented rabbits treated with subcutaneous alpha-melanocyte--stimulating hormone (20 micrograms/kg) synthesized normal amounts of cyclo-oxygenase products.

Endocarditis caused by Rochalimaea henselae.

A case of community-acquired, culture-negative, infective endocarditis was diagnosed in a 57-year-old construction worker. Small, pleomorphic gram-negative rods were seen in Brown-Hopps tissue gram stains and Warthin-Starry silver stains. The organism was identified as Rochalimaea henselae by polymerase chain reaction amplification and sequencing of the 16S rDNA gene sequence. This is the first report of infective endocarditis caused by R henselae.

Pseudomyxoma peritonei in women: a clinicopathologic analysis of 30 cases with emphasis on site of origin, prognosis, and relationship to ovarian mucinous tumors of low malignant potential.

Pseudomyxoma peritonei (PMP) is a poorly understood condition characterized by the accumulation of abundant mucinous material within the peritoneal cavity and associated with a mucinous tumor of the gastrointestinal tract or ovaries. Recently there has been considerable debate over the primary site of origin of the tumor associated with PMP in women. Some investigators have proposed a primary site in the ovaries, whereas others favor the gastrointestinal tract or the peritoneum. Another confusing issue has been the nature of the ovarian mucinous tumors associated with PMP. Although these neoplasms may be frankly malignant, more often they show minimal cytologic atypia and epithelial proliferation and have been classified as borderline or low malignant potential tumors. In order to address the issues of site of origin and nature of the associated ovarian mucinous tumors, we studied 68 cases of PMP in women, 30 of whom had mucinous tumors involving the ovaries. All 30 of these cases had an associated mucinous appendiceal or intestinal tumor. The PMP cases with ovarian tumors were compared with 30 ovarian mucinous tumors of low malignant potential (LMP). Based on the analysis of the primary ovarian mucinous LMP tumors, a set of criteria was formulated and used to determine the probable site of origin of PMP in the 30 women with mucinous tumors involving the ovaries. The following gross and microscopic features of the ovarian tumor were considered to be inconsistent with a primary ovarian origin: (1) surface involvement with or without superficial stromal involvement only; (2) adenocarcinoma with signet ring cell differentiation, with a previously diagnosed or concurrent appendiceal tumor of similar morphology; (3) bilateral adenocarcinoma consistent with colonic or appendiceal morphology; and (4) unilateral adenocarcinoma consistent with colonic or appendiceal morphology with a history of a colonic or appendiceal adenocarcinoma. When any one of these features was present the ovarian tumor was diagnosed as secondary. The following additional features also were considered to be more typical of secondary ovarian involvement: (1) normal or only slightly enlarged ovaries; (2) bilateral ovarian involvement; (3) simple or only focally proliferative mucinous epithelium with abundant extracellular mucin in cases with predominantly surface involvement of the ovaries, with or without a history of/or concurrent appendiceal adenoma; (4) multifocal or extensive pseudomyxoma ovarii in cases with stromal involvement, with or without a history of/or concurrent appendiceal adenoma; (5) ruptured appendiceal adenoma and unruptured ovarian tumor of similar histology; and (6) presence of an associated mucinous intestinal tumor.(ABSTRACT TRUNCATED AT 400 WORDS)

The Ocular Hypertension Treatment Study: design and baseline description of the participants.

BACKGROUND: The Ocular Hypertension Treatment Study (OHTS) seeks to evaluate the safety and efficacy of topical ocular hypotensive medication in preventing or delaying the onset of visual field loss and/or optic nerve damage in subjects with ocular hypertension at moderate risk for developing primary open angle glaucoma. OBJECTIVE: To describe the study protocol, the questions to be answered, and the baseline characteristics of the subjects. DESIGN: Multicenter randomized clinical trial with 2 groups: topical ocular hypotensive medication and close observation. SETTING: Subjects were enrolled and evaluated at 22 participating clinical centers. Visual fields and stereoscopic optic disc photographs were read in masked fashion. METHODS: We determined eligibility from a comprehensive eye examination, medical and ocular history, visual field testing, and stereoscopic optic disc photography. RESULTS: We describe the baseline characteristics of 1637 subjects randomized between February 28, 1994, and October 31, 1996. The mean age was 55 years; 56.9% of the subjects were women; and 25% were African American. The baseline intraocular pressure was 24.9 +/- 2.7 mm Hg (mean +/- SD). Systemic diseases and conditions reported by subjects included previous use of medication for ocular hypertension, 37%; systemic hypertension, 38%; cardiovascular disease, 6%; diabetes mellitus, 12%; and family history of glaucoma, 44%. The mean horizontal cup-disc ratio by contour estimated from stereophotography was 0.36 +/- 0.18. Qualifying Humphrey 30-2 visual fields had to be normal and reliable for entry into the study. Health-related quality of life (36-item short form health survey) scores in the OHTS sample were better than the age- and sex-matched population norms. African American subjects had larger baseline cup-disc ratios and higher reported rates of elevated blood pressure and diabetes than the rest of the subjects. CONCLUSIONS: The intraocular pressure among enrolled subjects was sufficiently high to provide an adequate test of the potential benefit of ocular hypotensive medication in preventing or delaying glaucomatous damage. The large number of African American subjects enrolled should provide a good estimate of the African American response to topical medication.

A simplified test of epinephrine responsiveness.

Forty-three ocular hypertensive and 33 ocular normotensive subjects received two doses of topical 1% epinephrine hydrochloride in one eye. The epinephrine was administered twice, ie, at time "zero" (8 AM) and 12 hours later (at 8 PM). The mean intraocular pressure responses at four hours and at 24 hours (12 hours after the last dose of epinephrine) were significantly correlated, r = 0.59 (P less than .001). This suggested that the simpler four-hour test was an equally accurate measure of the ocular responsiveness to topical epinephrine.

Intraocular pressure response to topical epinephrine and HLA-B12.

Twenty high responders to topical corticosteroids (intraocular pressure greater than 31 mm Hg after six weeks of topical 0.1% dexamethasone, four times daily) and 20 low responders (IOP less than 20 mm Hg) of similar age, sex, race, initial IOP, and facility of outflow were selected. After 24 hours of treatment (two doses) of topical 1% epinephrine hydrochloride, the high corticosteroid responders showed a mean (+/-SD) corrected decrease in IOP of 3.6 +/- 2.0 mm Hg as opposed to 1.8 +/- 2.1 mm Hg in the low corticosteroid responders. Within both corticosteroid groups, individuals with the antigen HLA-B12 showed significantly greater decreases in IOP. This suggested that the presence of HLA-B12 was not only associated with increased responses to corticosteroids but also to epinephrine.

A miniature compliance monitor for eyedrop medication.

We developed an eyedrop medication monitor that electronically records the date and time of each medication administration over a six-week period. It records a medication usage in a 15-minute interval when the cap is removed from the bottle and the bottle is inverted. The electronic components housed inside the bottle weigh 7.5 g, including the batteries, and the total volume of the circuit is 7.5 cc. The monitor resembles commercially available 30-mL eyedrop bottles in size, shape, and weight. The monitor is accurate when tested against known patterns of usage. The electronic eyedrop monitor should be useful in assessing compliance with eyedrop medications.

Prognostic factors in glaucomatous visual field loss.

A retrospective review was conducted of 31 patients with bilateral elevations of intraocular pressure and unilateral glaucomatous visual field loss. Nine (29%) of the fellow eyes developed visual field loss during a three- to seven-year follow-up period. Of the 13 fellow eyes that had an initial intraocular pressure greater than 26 mm Hg, eight (62%) developed visual field loss, as opposed to one (6%) of the 18 eyes that had lower intraocular pressures. Of the 11 fellow eyes whose intraocular pressures exceeded 24 mm Hg, either treated or untreated, on more than 50% of the measurements, seven (64%) lost visual field, whereas in the 20 eyes whose intraocular pressures were lower, only two )10%) lost visual field.

Increased corneal thickness simulating elevated intraocular pressure.

A 17-year-old girl had intraocular pressure readings of 30 to 40 mm Hg in both eyes, with normal visual fields and optic nerve heads. Medical treatment was unsuccessful in lowering the IOP measurements substantially. The central corneal thickness was 0.90 mm in each eye in the absence of corneal edema. Cannulation of the left anterior chamber revealed an IOP of 11 mm Hg, while the Perkins' and Schiotz' tonometers gave readings of 35 and 34 mm Hg, respectively. Previously, elevated tonometry readings had been obtained by Goldmann's, Perkins', Schiotz', MacKay and Marg's, pneumatic tonometer and air puff tonometer. This suggested that measurement of central corneal thickness be performed in cases in which IOP recordings do not correspond to other clinical findings.

Timolol maleate: efficacy and safety.

A randomized, double-masked trial of various concentrations of timolol maleate ophthalmic solution (0.1%, 0.25%, 0.5%, and 1.0%) vs placebo demonstrated that all concentrations of timolol effectively lowered intraocular pressure (IOP). A 0.5% solution of timolol was as effective in reducing IOP as the 1.0% concentration. Blood pressure, visual acuity, and pupillary diameter were not altered significantly by any concentration of timolol tested during this study. There was a dose-dependent decrease in resting pulse rate with increasing concentrations of timolol. No objective signs of drug intolerance were found on external ocular examination, nor were any subjective symptoms elicited on questioning the subjects. Timolol applied topically twice daily in concentrations of 0.1% to 0.5% appeared to be an effective and safe ocular hypotensive agent.

Histocompatibility antigens and primary open-angle glaucoma. A reassessment.

Histocompatibility (HLA) antigen typing was performed on 306 patients who had been studied and classified carefully. Black individuals with primary open-angle glaucoma (POAG) had no significant differences in HLA antigen prevalences from black control subjects. In one white population with POAG, a significant decrease in HLA-A1, a significant increase in HLA-Aw31, and a significant increase in the antigen combination HLA-B7 and HLA-Bw22 were noted. However, these differences were not confirmed in a second white population with POAG. We concluded that associations between the A and B loci of the HLA antigen system and POAG were not as impressive as has been previously reported.