Interpersonal autonomic synchrony and sexual satisfaction: A preliminary examination

Introduction

A growing body of literature has increased our understanding of interpersonal autonomic synchrony (IAS), or exchanges across biological systems resulting in physiological covariation. While research suggests that IAS is more likely in relationships characterized by emotional intimacy, no research to date has examined the connection between IAS and the quality of sexual relationships.

Objectives

The current study seeks to elucidate the relationship between IAS and sexual satisfaction (SS) using tasks that have previously been used to assess synchrony (i.e.,gazing, mirroring), as well as several conversation-based tasks (i.e., neutral and sex-related conversation tasks).

Methods

Couples (n=28) completed procedures in a laboratory-based setting where they completed survey measures of SS before connecting to an electrocardiogram. Subsequently, heart rate (HR) data for each dyad were analyzed using a moderated multi-level modeling approach.

Results

IAS was detected, with men reliably predicting the HR of female partners, and women reliably predicting the HR of male partners (respectively, β=0.383, p<0.001; β=0.222, p<0.001). AIC values indicate a better fitting model for men predicting female HR. As such, moderation analyses were conducted for that model by study task, finding a significant interaction between SS and observed IAS during the mirroring task (β=0.004, p=0.009) and neutral-conversation task (β=0.016, p=0.009).

Conclusions

These findings reflect evidence that IAS may be relevant to SS at the couple-level. The ability of couples to coregulate while attempting to synchronize (as in the mirroring task) or exchange information (as in the neutral-conversation task) may meaningfully change how they experience their sexual relationship.

Disclosure

No significant relationships.

A Multidimensional Evaluation of Intimacy

Introduction

Supportive, nurturing relationships facilitate good health, well-being, and life satisfaction. Intimacy is crucial for developing successful relationships as it strengthens bonds between partners through the exchange of personal details, love, and affection. Despite the importance of intimacy in developing strong relationships, the extant research often conflates affection, trust, and sexual acts with intimacy or only considers one aspect of an intimate relationship (i.e., physical or sexual touch) .

Objectives

The current study aimed to clarify what elicits feelings of intimacy in men and women in order to develop a more nuanced conceptualization of intimacy for use in future research and clinical practice.

Methods

In Study 1, women and men nominated over 2,700 items that “elicited feelings of intimacy” for them. Examples of nominations included: trust, communication, touch, attraction, and sex. Trained raters condensed duplicate items and created a final list of unique nominations for use in Study 2. Study 2 identified the factor structure of the nominated items by having a new sample of participants rate the extent each item elicited intimacy for them.

Results

Data collection is ongoing but will be completed by December 2021. Results will be updated with an addendum after data analysis.

Conclusions

will focus on gender differences in the factor structure of intimacy, how future research can avoid conflating this important construct with other relational aspects, and how a deeper understanding of intimacy can benefit treatment in clinical contexts and strengthen relationships more broadly.

Disclosure

No significant relationships.

Abstract P2-13-03: Complications following total skin-sparing mastectomy and expander-implant reconstruction: Effects of radiation therapy on the stages of reconstruction

BACKGROUND

With increasing numbers of patients requiring post-mastectomy radiation therapy (PMRT), many patients undergoing total-skin sparing mastectomy (TSSM) and immediate two-staged expander-implant (TE-I) reconstruction will receive radiation therapy (XRT) during the course of their reconstruction. Additionally, many patients undergoing TSSM for recurrent cancer have a history of prior lumpectomy and XRT. While the increased risk of reconstructive complications in the setting of XRT has been well-documented, few studies have looked at the impact of XRT on the stages of TE-I reconstruction.

METHODS

All patients undergoing TSSM and immediate two-staged TE-I reconstruction between 2006 and 2013 were identified from a prospectively maintained database. The incidences of TE-I loss and severe infection requiring admission for IV antibiotics were assessed in the subsets of patients with a prior history of XRT and those who received PMRT. Complications were divided into those following the first stage of reconstruction (TSSM and TE placement) and those following the second stage (TE-I exchange).

RESULTS

A total of 218 TSSM and TE-I reconstruction cases were included in the analysis, 85 (39%) with prior XRT and 133 (61%) with PMRT, all of whom who received PMRT prior to TE-I exchange. Mean follow-up time was 2.5 years. Nearly all cases of prior XRT occurred in patients who developed a local recurrence and then underwent TSSM; mean time from prior XRT to TSSM was 7 years (range: 2 months to 22 years). Patients with prior XRT were much more likely to develop complications following the first stage of reconstruction than after the second stage (TE-I loss: 15% vs. 4%, p = 0.02; infection: 20% vs. 8%, p = 0.02). Patients who received PMRT had low rates of complications following the first stage of reconstruction, when they had not yet received any radiation exposure (TE-I loss: 3%; infection: 8%). However, rates increased significantly following TE-I exchange, with an 18% TE-I loss and 30% rate of infection, which was nearly 4-fold higher than patients with a prior history of XRT.

CONCLUSIONS

Patients with prior XRT are at significantly increased risk of reconstructive complications following the first stage of TE-I reconstruction after TSSM, even with a remote history of XRT. However, if these patients are able to successfully maintain their reconstruction through tissue expansion, their risk of complications at the second stage is comparable to patients without radiation exposure and significantly lower than patients receiving PMRT. Careful patient selection and appropriate pre-operative counseling for TSSM and TE-I reconstruction is critical to optimize outcomes and set appropriate expectations.

Citation Format: Sears M, Warren Peled A, Wang F, Foster RD, Alvarado M, Wong J, Ewing CA, Esserman LJ, Sbitany H, Fowble B. Complications following total skin-sparing mastectomy and expander-implant reconstruction: Effects of radiation therapy on the stages of reconstruction. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-13-03.

Effect of closure and packaging type on 3-alkyl-2-methoxypyrazines and other impact odorants of Riesling and Cabernet Franc wines

3-Alkyl-2-methoxypyrazines (MPs) represent an important and potent class of grape- and insect-derived odor-active compounds associated with wine quality. Thirty nanograms per liter each of 3-isobutyl-2-methoxypyrazine (IBMP), 3-isopropyl-2-methoxypyrazine (IPMP), and 3-sec-butyl-2-methoxypyrazine (SBMP) was added to Riesling and Cabernet Franc wines and monitored with headspace solid-phase microextraction and gas chromatography-mass spectrometry over 18 months to investigate the effects of various closure and packaging options on MPs. Changes in MP concentrations during bottle aging varied with closure/packaging option, with the greatest decrease evident in Tetrapak cartons. After 18 months, IBMP, IPMP, and SBMP in both Tetrapak-stored wines decreased by approximately 45, 32, and 26%, respectively. Similar changes were observed in other impact odorants to previous studies, including a greater decrease in odorant concentrations in wines closed with synthetic corks compared to natural corks and screw caps. These differences are thought to be due to the differential sorptive capacities of the various closure types. Overall, the data suggest that differences in gas permeability/contribution from the different closure and packaging options strongly associate with changes in wine composition during aging.

Detection thresholds for 2-isopropyl-3-methoxypyrazine in Concord and Niagara grape juice

2-isopropyl-3-methoxypyrazine (IPMP) is the compound responsible for the off-flavor known as ladybug taint, which occurs when Harmnonia axyridis beetles become incorporated with the grapes during juice processing. It is also an important grape-derived component of juice flavor in some varieties. The main objective of this study was to determine the orthonasal (ON) and retronasal (RN) detection thresholds for IPMP in juice. The ASTM E679 ascending forced choice method of limits was used to determine detection thresholds for 26 individuals in Concord and Niagara juices. Group best estimate thresholds (BETs) averaged 0.93 ng/L and were 50% and 21% higher in Concord than in Niagara juices for ON and RN evaluation, respectively. Group BETs for IPMP (ng/L) for Concord were ON: 1.11; RN: 1.02 and for Niagara were ON: 0.74; RN: 0.84. Variation in individual detection thresholds was observed, although familiarity with ladybug taint was not associated with individual threshold values. We conclude that humans are very sensitive to IPMP in juice, and that detection thresholds are more strongly influenced by grape variety than evaluation mode. These results may assist juice producers in establishing tolerance levels for IPMP in juice affected by ladybug taint or derived from grapes of suboptimal ripeness.

Determination of ortho- and retronasal detection thresholds for 2-isopropyl-3-methoxypyrazine in wine

2-Isopropyl-3-methoxypyrazine (IPMP) is a grape-derived component of wine flavor in some wine varieties as well as the causal compound of the off-flavor known as ladybug taint (LBT), which occurs when Harmonia axyridis beetles are incorporated with the grapes during juice and wine processing. The main objective of this study was to obtain robust estimates of the orthonasal (ON) and retronasal (RN) detection thresholds (DTs) for IPMP in wines of differing styles. The ASTM E679 ascending forced choice method of limits was used to determine DTs for 47 individuals in 3 different wines--Chardonnay, Gewürztraminer, and a red wine blend of Baco Noir and Marechel Foch. The group best estimate thresholds (BETs) obtained for IPMP (ng/L) were Chardonnay, ON: 0.32; Gewürztraminer, ON: 1.56, RN: 1.15, and red wine blend, ON: 1.03, RN: 2.29. A large variation in individual DTs was observed. Familiarity with LBT was inversely correlated with DTs for Gewürztraminer, and no difference in thresholds was observed between winemakers and nonwinemakers. We conclude that the human DT for IPMP is extremely low and influenced significantly by wine style and evaluation mode. We recommend against the reporting of single-threshold values for wine flavor compounds, and encourage the determination of consumer rejection thresholds for IPMP in wine.

Regular versus as-needed short-acting inhaled beta-agonist therapy for chronic obstructive pulmonary disease

Regular short-acting inhaled beta-agonist therapy is of uncertain benefit in patients with chronic obstructive pulmonary disease (COPD). We conducted a randomized, concealed, double-blind, placebo-controlled crossover trial in two periods, each of 3-mo duration, involving 53 patients with a smoking history of > 20 pack-years, an FEV1 of < 70% predicted, and an FEV1/VC ratio of < 0.7 after inhalation of 200 microg albuterol. All patients received regular ipratropium bromide at 20 microg per puff in 2 puffs four times daily, beclomethasone at 250 microg per puff or equivalent corticosteroid in 2 puffs twice daily, and open-label inhaled albuterol as needed. Interventional therapy consisted of regular inhaled albuterol (100 microg per puff, in 2 puffs four times daily) versus placebo. Patients used twice as much active albuterol in the regular use period (mean: 8.07 puffs of coded and 4.68 puffs of open-label medication; total: 12.75 puffs daily) than during the as-needed period (mean: 6.34 puffs of open-label albuterol daily). Despite greater beta-agonist use, patients showed similar results during treatment and control periods for all outcomes. Differences between active and placebo periods were: FEV1: -0.04 L (95% confidence interval [CI]: -0.09 to 0.01 L); slow vital capacity: 0.04 L (95% CI: -0.12 to 0.20 L); 6-min walk test distance: -3.1 m (95% CI: -16.8 to 10.5 m); and Chronic Respiratory Questionnaire scores for dyspnea: 0.02 (95% CI: -0.13 to 0.16); fatigue: -0.02 (95% CI: -0.25 to 0.20); mastery: 0.01 (95% CI: -0.20 to 0.24); and emotional function: 0.02 (95% CI: -0.20 to 0.24). We found that in patients with COPD, use of regular short-acting inhaled beta-agonists resulted in twice as much beta-agonist use without physiologic or clinical benefit as did use on an as-needed basis.

pICln can regulate swelling-induced Cl- currents in either layer of rabbit ciliary epithelium

Swelling-induced Cl- currents were investigated in freshly prepared non-pigmented epithelial (NPE) and pigmented epithelial (PE) cells of the rabbit ciliary body using the whole-cell patch clamp technique. Exposure of both NPE and PE cells to hypotonic stress induced Cl- currents that exhibited outward rectification and were insensitive to Ca+2. We found that swelling-induced Cl- currents in PE cell are observed shortly after isolation. The swelling-induced Cl- current showed little or no inactivation at positive membrane voltages and was sensitive to 100 microM NPPB and 100 microM DIDS. Injection of cRNA encoded rabbit pICln into Xenopus oocytes produced an outwardly rectifying Cl- current displaying features consistent with the swelling-induced Cl- current in epithelium. pICln is ubiquitous in the ciliary epithelium. It participates in the equilibration of short term tonicity alterations, a phenomenon underlying mechanisms with larger and slower amplitudes for aqueous secretion by these cells.

Adrenergic-mediated connexin43 phosphorylation in the ocular ciliary epithelium

PURPOSE

Gap junctions provide metabolic cooperativity between the nonpigmented and pigmented cells of the ciliary epithelium. Connexin43 is the major protein of these junctions. To learn whether the phosphorylation state of this gap junction is sensitive to adrenergic mediators, we exposed isolated intact ciliary epithelia to agonists of the G-protein receptor-coupled system and analyzed the phosphorylation state of connexin43 by western blot.

METHODS

The double layer of intact ciliary epithelia was isolated and exposed to isoproterenol, forskolin, and the tumor promoter 12-o-tetradecanoylphorbol-13-acetate (TPA). The phosphorylation state of connexin43 was analyzed by western blot, using a monoclonal antibody that recognized both the phosphorylated and dephosphorylated connexin43. An upward shift in electrophoretic mobility confirmed the presence of a phosphate group.

RESULTS

Connexin43 phosphorylation was rapidly induced by each of these agonists. One microM isoproterenol and 5 microM forskolin induced phosphorylation of connexin43, as did 16 nanomolar TPA. The effect of isoproterenol was partially blocked by 1 microM timolol. Addition of a phosphatase after forskolin treatment reversed the effect of forskolin. Control explant tissue not treated with these agents exhibited a slower but definite phosphorylation of connexin43.

CONCLUSIONS

Phosphorylation of ciliary epithelial connexin43 is sensitive to modulators of the cAMP system as well as an agent that activates PKC. Isolated intact ciliary epithelia phosphorylate connexin43 by endogenous mechanisms, most likely as a protective response to stress.

Cloning and functional expression of a swelling-induced chloride conductance regulatory protein, plCln, from rabbit ocular ciliary epithelium

The cDNA encoding a swelling-induced chloride conductance regulatory protein, plcln, was cloned from rabbit ciliary epithelium by using a polymerase chain reaction (PCR)-based approach. The open reading frame encoding 236 amino acids possesses high amino acid identity (93/%) with the previously cloned plcln from human ciliary epithelium. Outwardly rectifying currents were recorded in Xenopus oocytes injected with plcln cRNA, a result consistent with plcln expression in ciliary epithelium. A widespread distribution and marked expression of plcln mRNA in both nonpigmented ciliary epithelial (NPE) cells and pigmented ciliary epithelial (PE) cells was found for the first time. In situ hybridization analysis showed that plcln expression is more abundant in NPE than PE. These findings are consistent with the idea that plcln may be an important regulatory element in these secretory cells.

A low conductance chloride channel in the basolateral membranes of the non-pigmented ciliary epithelium of the rabbit eye

PURPOSE

Chloride efflux plays an important role in aqueous humor production. Chloride currents have been described in bovine non-pigmented ciliary epithelium (NPE), in transformed cultured human NPE, and in bovine volume-activated chloride channels described in the latter. It is the basolateral membranes of the NPE of ocular ciliary processes that comprise the exit pathway for the process of aqueous secretion performed by the double syncytial layer of ciliary epithelium, however. Therefore, we studied both cell-attached, and, excised, inside-out patches from basolateral membranes of the NPE.

METHODS

Cell-attached and cell-free excised patches were formed from the basolateral membranes of NPE and single channel currents recorded with a Dagan 3900A patch clamp amplifier.

RESULTS

A low conductance channel of 14 pS was observed and recorded in 30% of cell attached patches and in 35% of excised inside out patches under symmetrical conditions (160 mM chloride). This channel displayed a nearly linear current-voltage relationship, with an open probability that was not voltage-dependent. The channel was chloride-selective: N-methyl-D-glucamine (NMDG) used as cation did not alter the current profile nor the reversal protein. Further, with inside-out patches, the reversal potential was close to zero (0.3 +/- 0.5 mV (10) in symmetrical (160 mV) chloride, but shifted to -32.3 +/- 0.5 mV (5) when the concentration of chloride in the bathing solution was reduced to 40 mM while the recording pipette was held at 160 mM. This value approaches the theoretical equilibrium potential of chloride for these conditions. The channel anion permeability sequence was: I- > NO3- > or = Br- > Cl- > gluconate- approximately equal to aspartate-. Three different chloride-channel blockers inhibited the channel activity.

CONCLUSION

A low conductance channel, selective for chloride, and, modulated by beta adrenergic and VIP stimulation, based on it sensitivity to exogenously added cAMP, ATP and the catalytic subunit of PKA, is present in the exit basolateral membranes of rabbit NPE and contributes to the process of aqueous humor formation.

Circadian aqueous flow mediated by beta-arrestin induced homologous desensitization

It was hypothesized that homologous desensitization regulates signal transduction from the beta-adrenergic receptor in the ocular ciliary epithelium to affect the circadian rhythm of aqueous humor secretion. beta-arrestin-1 was cloned from the rabbit ciliary epithelium, and the full length cDNA used as a probe for Northern blot analysis to examine the diurnal expression of beta-arrestin mRNA. Protein expression of beta-arrestin-1 at intervals during the circadian cycle of aqueous secretion showed a decrease in beta-arrestin expression when maximal activation of the beta-adrenergic receptor is known to increase secretion. Diurnal expression of beta-arrestin suggests that homologous desensitization can regulate the circadian rhythm of aqueous flow.

Calcium signals from intact rabbit ciliary epithelium observed with confocal microscopy

PURPOSE

We investigated patterns of evoked calcium signals to learn about the function of the calcium second messenger system in ciliary epithelium.

METHODS

Isolated infact ciliary processes were loaded with fluo-3/AM and observed with a Bio-Rad MRC-600 laser scanning confocal imaging system, before, during, and after perfusion with catecholamines, cholinergic agents, and autocoids.

RESULTS

One microM acetylcholine (ACH) and 10 microM carbachol (CARB) induced an atropine-sensitive increase in intracellular free calcium ion concentration ([Ca2+]i), considerably greater in NPE than in PE. 10 microM epinephrine (EPI) and 100 microM phenylephrine (PHE) increased [Ca2+]i in NPE and PE, in this case PE > NPE. These effects were blocked by prazosin. 10 mM caffeine (CAF) increased of [Ca2+]i in NPE and PE (NPE > PE) and sometimes produced very slow oscillations with an interval of 10 to 25 s. Prior administration of CAF strongly suppressed the effects of ACH, CARB, EPI, PHE, histamine, and adenosine 5-triphosphate (ATP). One hundred microM ryanodine (RYA) or thapsigargin (TG) increased [Ca2+]i in NPE and PE (NPE > PE).

CONCLUSIONS

In the ciliary epithelium: (1) different patterns of evoked transients and oscillations of calcium were seen in response to agonists; (2) NPE appeared to contain a predominance of muscarinic receptors, while the PE is dominated by alpha 1-adrenergic receptors and (3) the increase in [Ca2+]i by CAF or RYA or TG in either cell layer and the blocking effects of these agents upon agonist, evoking increases in [Ca2+]i, suggested involvement of both the cyclic adenosine diphosphate ribose and the inositol 1, 4, 5 triphosphate (InsP3) systems in the regulation of intracellular calcium.

Spontaneous and evoked oscillations of cytosolic calcium in the freshly prepared ciliary epithelial bilayer of the rabbit eye

Under confocal microscopy, calcium imaging of the isolated secretory ciliary epithelium, especially the inner layer, non-pigmented epithelium (NPE), revealed spontaneous calcium oscillations in multiple patterns. Oscillations induced by stimulation of the muscarinic receptor have an onset that coincides with synthesis and release of InsP3. Caffeine (5 mM) induced a calcium transient and blocked spontaneous and (0.1 mM) muscarine induced oscillations. Thapsigargin (1 microM) prevented a muscarinic response. Muscarine and caffeine induced transients have significantly greater amplitude in NPE than in PE (outer layer, pigmented epithelium). Calcium transients and frequencies of spontaneous oscillations are greater in NPE than PE. In NPE muscarine induced oscillations are observed with higher frequencies than the spontaneous ones: gamma-0.24 +/- 0.05Hz (8) versus 0.08 +/- 0.01Hz (18). These repetitive responses, spontaneous and receptor coupled, reflect intracellular coding of information. A calcium signal may contribute to the regulation of aqueous humor formation.

Regulation and bioelectrical effects of cyclic adenosine monophosphate production in the ciliary epithelial bilayer

PURPOSE

To determine whether the intact isolated ciliary epithelial bilayer retains the alpha-2 and beta adrenergic receptor activation and interaction described for whole ciliary processes and whether this pure epithelial bilayer displays bioelectric parameters sensitive to alterations in cyclic adenosine Monophosphate (cAMP) production induced by adrenergic compounds.

METHODS

The intact ciliary epithelial bilayer of the rabbit eye isolated by perfusion was mounted in a specially constructed Ussing-type chamber. The transepithelial potential difference and short-circuit current were monitored for effects induced by agents that stimulated or blocked (some did both) caMP production. Using a radioimmunoassay, the latter were studied in the pure epithelial bilayers and in whole ciliary processes.

RESULTS

A reproducible increase in cAMP production and an increase in the short-circuit current induced in the bilayer by isoproterenol, a nonspecific beta adrenergic agonist, were both blocked by pretreatment with either timolol, a nonspecific beta adrenergic blocking agent, or with para-aminoclonidine, an alpha-2 agonist. Maximal stimulation of cAMP with forskolin in this pure isolated epithelial preparation yields a response that is 60% of the value found in whole processes, indicating that the latter tissue contains responsive sites that are nonepithelial, probably vascular, or perhaps stromal. The degree of inhibition of the beta adrenergic receptor by alpha-2 agonists was not very different in the two preparations. On the other hand, inhibition of the epithelial vasointestinal peptide receptor by neuropeptide Y or alpha-2 agonism was considerably heightened in the pure bilayered epithelial preparation.

CONCLUSIONS

The isolated intact ciliary epithelial bilayer, when stimulated with beta adrenergic receptor agonists, vasointestinal peptide, or forskolin, produces increased cAMP and its transepithelial potential becomes hyperpolarized. These chemical and bioelectrical effects are prevented by pretreatment with either alpha-2 adrenergic agonists or beta adrenergic blocking agents. The results obtained in the isolated intact purely epithelial ciliary bilayer confirm that the ciliary epithelium is the source of adrenergic receptor activation and interaction and support the hypothesis that aqueous humor production is regulated by interactions between epithelial alpha-2 and beta adrenergic receptors.

Postmortem diagnosis of Fusarium panophthalmitis by the polymerase chain reaction

PURPOSE

We undertook this study to determine if a polymerase chain reaction-based test that we developed for the filamentary fungus, Fusarium, could be used to detect the organism in postmortem ocular tissues.

METHODS

We applied the polymerase chain reaction to amplify a target fragment of Fusarium DNA from formalin-fixed ocular tissues from a patient with endogenous Fusarium panophthalmitis.

RESULTS

By using the polymerase chain reaction-based test, we were able to amplify the target fragment of DNA from the infected eyes, but not from uninfected control eyes.

CONCLUSIONS

The technique appears to hold promise to be a sensitive, specific, and rapid method of diagnosing Fusarium infections.

Transepithelial transport of ascorbic acid by the isolated intact ciliary epithelial bilayer of the rabbit eye

The purpose of these experiments was to test whether the isolated intact epithelial bilayer derived from rabbit ciliary processes transports ascorbic acid and to what degree the transport rate in vitro corresponds to the in vivo process. The intact ciliary epithelial bilayer of the rabbit eye isolated by perfusion was mounted in a particularly constructed Ussing type chamber. Fluxes were measured by additions of 14C ascorbate to the hemichamber on either the pigmented epithelium (PE) or the nonpigmented epithelium (NPE) side where equal concentrations of ascorbate from .02 to 2.0 mM were present. Samples were taken at intervals thereafter and counted in a liquid scintillation counter. The experiments were done under short circuit conditions to avoid the possible influence of fluctuating currents upon the movement of ascorbate. Like the earlier iris ciliary body preparations, separation of ascorbate fluxes is also done by the isolated intact ciliary epithelial bilayer, and the transport of ascorbic acid proceeds by saturation kinetics. The uptake process is accomplished entirely by the pigmented epithelium (PE). The Km of the process is 0.97 mM, and Vmax was valued at 130 nM/L/hr. Thus, assuming an aqueous flow rate of 2 microliters/min, the transfer of ascorbic acid across the bilayer occurs at a rate required to maintain the ordinary millimolar concentration of ascorbic acid in the aqueous humor found in vivo.

Metabolic neuropathy

In this article a review and summary of peripheral neuropathies secondary to metabolic disorders, affecting the lower extremity, have been presented. The clinical presentation of individual symptomatology is variable depending on the nature and chronicity of illness. The clinical features that the podiatric physician must recognize is weakness, sensory, and gait disturbances resulting from these syndromes. Some disorders are reversible if recognized and treated early in their course. Thus, a thorough general history and physical examination is required of all patients presenting with apparent podiatric symptomatology.

Adenylate cyclase stimulation and intraocular pressure reduction by forskolin analogs

Forskolin and 18 chemical analogs of forskolin were assayed for stimulation of adenylate cyclase activity in vitro and for their effects on intraocular pressure (IOP) in vivo. Adenylate cyclase activity was determined with a preparation of corpora striata from male Wistar rats and test drug concentrations of 0.3 to 300 microM. IOP effect was monitored after a single topical ocular application of a 1% suspension of the test drug to male New Zealand albino rabbits. Significant reductions in IOP occurred with compounds which had potent cyclase stimulatory properties. Most compounds with little cyclase stimulatory effect produced little or no decrease in IOP. A 1-substituted morpholino-acetoxy derivative, which may be a prodrug metabolized to active form by corneal esterases, showed little cyclase stimulation in vitro but produced significant reductions in IOP.

Quantitative evaluation of the optic nerve head in patients with unilateral visual field loss from primary open-angle glaucoma

Measurable structural alterations of the optic nerve head may precede visual field abnormalities in early open-angle glaucoma. The authors studied the optic nerve heads of 10 patients with unilateral visual field loss from primary open-angle glaucoma, and 12 age- and sex-matched normal subjects. Topographic optic nerve head parameters were measured with a system of computerized image analysis (Rodenstock Analyzer, G. Rodenstock Instrumente GMBH, Munich, W. Germany). In patients with asymmetric primary open-angle glaucoma, eyes with normal visual fields had a slightly larger mean (+/- standard error of the mean) disc rim area (0.90 +/- 0.04 mm2) than eyes with glaucomatous visual field defects (0.78 +/- 0.05 mm2). However, both sets of eyes in the asymmetric primary open-angle glaucoma patients had smaller mean disc rim areas (P less than 0.0007) than did the control group (1.27 +/- 0.09 mm2). These findings support the hypothesis that loss of the optic disc rim can be detected before perimetric abnormalities develop in primary open-angle glaucoma.

Patterns of early visual field loss in open-angle glaucoma

We examined two groups of patients with primary open-angle glaucoma with distinctly different patterns of early visual field loss using two visual field indices: mean defect and loss variance. Patients were selected on the basis of visual field criteria only. Eight patients were selected for diffuse depression of the differential light sensitivity without localized scotomas (mean defect greater than 3.0 decibels, loss variance less than 10.0 decibels). Seven patients were selected for localized scotomas without diffuse depression of the differential light sensitivity (mean defect less than or equal to 3.0 decibels, loss variance greater than or equal to 20.0 decibels). Patients with diffuse depression manifested intraocular pressures that were higher (mean peak pressure +/- S.E.M., 27.6 +/- 1.2 mm Hg) than those with localized defects (22.4 +/- 1.4 mm Hg). The optic disk rim area of the localized loss group (mean +/- S.E.M., 1.02 +/- 0.15 mm2) was significantly smaller (P less than .05) than the disk rim area of the diffuse loss group (1.33 +/- 0.07 mm2). This difference was largely because of thinner temporal disk rims in the localized loss group. Different patterns of visual field loss may be caused by different mechanisms of glaucomatous optic nerve damage.

Celiprolol versus timolol and placebo: a two week double-blind comparison

Celiprolol (5%) was compared to timolol (0.5%) and placebo in patients with primary open angle glaucoma or ocular hypertension. A total of 28 patients participated in this double blind study and received treatment for two weeks. Intraocular pressure decreased an average of 4.4 mmHg with celiprolol and 7.1 mmHg with timolol two hours after instillation. This was maintained 12 hours after administration of timolol but not after celiprolol. There was a small but statistically significant decrease in pulse rate 2 hours after administration of timolol (from 72 to 64 beats per minute) which was not observed after celiprolol. Side effects were mild and similar for all 3 groups.

The effect of hCG on cyclic AMP in rabbit ciliary processes

Experiments designed to address the role of cyclic AMP as a mediator of the eye pressure and aqueous flow reducing effects of human chorionic gonadotropin (hCG) in the rabbit have been conducted. No significant stimulatory effect of hCG on particulate preparations of adenylate cyclase from rabbit ciliary processes could be found under several different experimental conditions. Forskolin, an activator of adenylate cyclase can, in some biological systems, reveal a significant hormonal cyclic AMP response which is undetectable in the presence of hormone alone. Forskolin did potentiate the effect of isoproterenol on cyclic AMP production by intact rabbit ciliary processes. Cyclic AMP production by intact ciliary processes was not affected by hCG, either in the presence or absence of forskolin. Significant specific binding of iodinated hCG to particulate preparations of rabbit ciliary processes could not be detected. These results dispute the role of cyclic AMP as a mediator of the flow and pressure reducing effects of hCG; however, theoretical and methodological complications relating to this interpretation are discussed.

Chorionic gonadotropin decreases intraocular pressure and aqueous humor flow in rabbit eyes

The effect of human chorionic gonadotropin (hCG) on the rabbit eye was studied. Intravitreal injections of hCG in albino rabbits provoked a reduction of intraocular pressure (IOP). Intravenous administration of hCG in single doses of 5,000-10,000 units in male pigmented rabbits caused a significant reduction in IOP from 1.5-5 hr after injection. When two successive intravenous doses of 5,000 units of hCG were given at 0 and 3 hr to pigmented rabbits, a significant reduction of net aqueous flow occurred, as measured by scanning fluorophotometry. These results indicate that the decrease in aqueous flow rate in the rabbit eye after administration of hCG can account for the reduction in IOP.

Reproducibility of optic disc measurements with computerized analysis of stereoscopic video images

Computerized digital image analysis of the optic nerve head was performed using a simultaneous stereoscopic video camera system to provide rapid, quantitative measurements of optic nerve head topography. Determination of the variability of the measurements is required to estimate the magnitude of optic nerve change over time that can be reliably detected. Total variability, operator variability, and interoperator variability were studied. Total variability was assessed by analyzing ten sets of video recordings made in each of seven eyes of seven normal subjects, and in seven eyes of seven patients with glaucoma. The median coefficients of variation for measurements of total variability in glaucoma patients were as follows: vertical disc measurement, 1.4%; horizontal disc measurement, 2.1%; disc area, 1.9%; vertical cup/disc, 3.9%; horizontal cup/disc, 3.3%; disc rim area, 7.5%; and volume, 7.6%. Operator and interoperator variabilities were considerably smaller in magnitude.

Regulation of intraocular pressure during cyclocryotherapy for advanced glaucoma

Five eyes of five patients with advanced glaucoma were treated with cyclocryotherapy. Intraocular pressure was monitored by applanation tonometry during the procedure and for the first 24 hours postoperatively. Two patients underwent a standard form of treatment, and exhibited two components of acute increases in intraocular pressure as a result of the procedure. Intraoperatively, intraocular pressure increased abruptly to 60 to 80 mm Hg during the freezing phase of cyclocryotherapy and decreased to baseline levels during the thaw phase. Postoperatively, intraocular pressure increased to approximately 50 mm Hg, peaking six hours after the procedure. We devised a method of manometric regulation of intraocular pressure to prevent significant increases during cyclocryotherapy and used it in three patients. This group maintained intraocular pressures of approximately 25 mm Hg intraoperatively, and exhibited blunted postoperative increases. Manometric regulation of intraocular pressure during cyclocryotherapy for advanced glaucoma may protect seriously compromised optic nerves from further damage, and may represent a safer method of treatment.

Ocular blood flow in phakic and aphakic monkey eyes

Alterations in regional ocular blood flow produced by topical epinephrine were studied in phakic and aphakic eyes of Macaca arctoides using the radioactive microsphere technique. Three isotopes were used to make sequential blood flow measurements just prior to topical epinephrine administration, 1 hr later and 3 hr later. Significant reductions of flow were found in the iris, ciliary body, and optic nerve head of both phakic and aphakic groups. Choroidal and posterior optic nerve flow decreased significantly in aphakic eyes only. Decreases in flow were flow decreased significantly in aphakic eyes only. Decreases in flow were maximal at 3 hr. Significant changes in retinal flow were not detected. The implications of these findings regarding epinephrine-induced aphakic cystoid macular edema and the suitability of epinephrine or its derivatives in the treatment of glaucoma are discussed.

Combined effect of forskolin and acetazolamide on intraocular pressure and aqueous flow in rabbit eyes

Forskolin, a diterpene, a potent and direct stimulator of the catalytic unit of adenylate cyclase, can reduce intraocular pressure when administered topically to rabbit eyes in a 1% suspension. Using an intravitreal plant of fluorescein-dextran, aqueous flow was measured by a modification of the method of Maurice. Forskolin reduces net aqueous flow by 51% compared to the controls. Acetazolamide (25 mg kg-1) administered intravenously reduces net aqueous flow by 45%. Forskolin and acetazolamide together reduce net aqueous flow by 72%, an important additive effect undoubtedly produced by different pathways.

[A new function of the non-pigmented epithelium of ciliary processes in the formation of aqueous humor]

The invagination of the optic vesicle has, as one of its consequences, the apposition of the apices of the nonpigmented and pigmented epithelia of the ciliary processes of the eye. There are well developed intercellular ciliary "channels" formed at the apices of these cells. Embryologically the ciliary epithelia are homologous to the epithelia of the choroid plexus, a characteristically differentiated ependyma. These epithelial cells have a polarity. For example, the supranuclear region of the nonpigmented epithelia has Golgi apparatus. While stimulation of the epithelia of the choroid plexus by beta adrenergics or cholera toxin increases the rate of production of cerebrospinal fluid, similar stimulation of the adenylate complex within the ciliary epithelia decreases aqueous humor production. When the secretory function of the nonpigmented epithelial cell is activated, fluid is probably reabsorbed from the posterior chamber and secreted apically into the intercellular ciliary channels, in accord with cell polarity, thereby reducing net aqueous inflow. The fluid may enter the ciliary stroma thereafter and thus may become part of what may be called "uveal scleral" flow, or in this instance, uveal flow. The anatomy, physiology, and chemistry fit this hypothesis and form the basis for new investigations of a two-way transport across the ciliary epithelia.

Human ciliary epithelia in monolayer culture

The ciliary epithelia of human (one to 12 months old) ciliary processes were isolated by trypsin and EDTA, cultured in Dulbecco's Modified Eagle Medium (DMEM) with 5% fetal calf serum and examined by phase and electron microscopy. The primary cultures were maintained for three to four months. Only a few non-pigmented epithelia adhered and none of them proliferated. After the first passage the culture seemed to consist of only the pigmented epithelia. Most cells were densely pigmented at first, then became less pigmented during successive proliferations. Half of the cells remained densely pigmented after the first subculture, another half remained less pigmented. The cells started to lose their pigment granules at four to six weeks in culture. After three months of culture, the cell sheets became entirely unpigmented. In thin section, most of the pigment granules in the cells at two weeks in culture were pre-melanosomes, and half of them were at the earliest stage of pre-melanosomes. Monolayer cells possessed basement membranes. At 14 weeks in culture, most cells established an apparent polarity, contained well-developed Golgi apparatus and rough endoplasmic reticulum and intermediate filaments, but no pigment granules. A bundle of intermediate filaments was found in the perinuclear cytoplasm. Multilayer cells presented a typical apex-to-apex and base-to-base configuration , and the extracellular material was detected only in the base-to-base intercellular spaces. Our culture system provided differentiated cells derived from the pigment epithelia of human ciliary processes.

Forskolin lowers intraocular pressure by reducing aqueous inflow

Forskolin is a diterpene derivative of the plant Coleus forskohlii that stimulates adenylate cyclase activity without interacting with cell surface receptors. Forskolin lowers the intraocular pressure of rabbits, monkeys, and humans. In rabbits, net aqueous humor inflow decreases, outflow facility remains unchanged, and ciliary blood flow increases. Tolerance to the intraocular pressure lowering effect did not occur in rabbits after topical doses given every 6 hr for 15 days. In vitro forskolin activates adenylate cyclase of crude particulate homogenates prepared from cultured human ciliary epithelia or from dissected ciliary epithelial processes of rabbit or human eyes. This activation is not blocked by timolol. The stimulation of adenylate cyclase by isoproterenol in vitro is potentiated in the presence of forskolin. Forskolin represents a potentially useful class of antiglaucoma agents differing in molecular mechanism of action from previously used drugs.

Intraocular effects of lipoxygenase pathway products in arachidonic acid metabolism

Arachidonic acid is metabolized through the lipoxygenase pathways to hydroperoxy acids (HPETEs), hydroxy acids (HETEs), and leukotrienes, derivatives of 5-HPETE. 5-HETE, 12-HETE, 15-HETE, and 15-HPETE were injected intracamerally in rabbits and leukotriene B4 (LTB4), leukotriene C4 (LTC4 and leukotriene D4 (LTD4) were injected intracamerally in guinea pigs, rabbits and cats. The effects on the intraocular pressure, aqueous humour protein and leukocyte concentration as well as pupil diameter were assessed. 5-HETE, 12-HETE, 15-HETE and 15-HPETE did not cause any change in the parameters studied. LTB4 caused a marked accumulation of leukocytes in the aqueous humour of cats and rabbits, and to some extent in guinea pigs. LTC4 and LTD4 were ineffective in guinea pigs and rabbits, but caused an intense long-lasting non-muscarinic miosis in cats. Thus, most of the lipoxygenase products tested showed little activity in the anterior segment of the eye, except LTB4, that caused leukocyte infiltration, and LTC4 and LTD4 that caused miosis in cats.

Ocular responses to leukotriene C4 and D4 in the cat

The effects of leukotriene C4 (LTC4) and D4 (LTD4) on the iridial smooth muscles, intraocular pressure, blood-aqueous barrier and regional blood flow in the eye have been studied in cats. The test compounds were injected into the anterior chamber. Both LTC4 and LTD4 caused a dose-dependent constriction of the pupil, the agents being about equipotent. The effect on the iridial sphincter muscle was not dependent on nerve conduction, cyclo-oxygenase products or muscarinic receptors. Maximal constriction was achieved with 0.1-1 microgram of the test compounds. The smallest dose to induce a decrease in pupil diameter was 0.01 microgram. After intracameral injection of 4 micrograms the miotic response was markedly delayed. This indicates that in high concentrations LTC4 and LTD4 probably also stimulate the iridial dilator muscle. The blood flow in the anterior uvea decreased after intracameral injection of 4 micrograms LTC4/LTD4. Smaller doses had no clear effect. There was no effect on the blood-aqueous barrier as judged from the aqueous humor protein concentration. The intraocular pressure decreased slightly after injection of the test compounds.

The adenylate cyclase receptor complex and aqueous humor formation

The secretory tissue of the eye, the ciliary processes, contains an enzyme receptor complex, composed of membrane proteins, the catalytic moiety of the enzyme adenylate cyclase, a guanyl nucleotide regulatory protein (or N protein), and other features. The enzyme can be activated by well-known neurohumoral or humoral agents, catecholamines, glycoprotein hormones produced by the hypothalamic pituitary axis, and other related compounds, including placental gonadotropin, organic fluorides, and forskolin, a diterpene. These compounds cause the ciliary epithelia to produce cyclic AMP at an accelerated rate. Cyclic AMP, as a second messenger, causes, either directly or indirectly, a decrease in the net rate of aqueous humor inflow that may be modulated by cofactors. Clinical syndromes fit the experimental data so that an integrated explanation can be given for the reduced intraocular pressure witnessed under certain central nervous system and adrenergic influences. The molecular biology of this concept provides important leads for future investigations that bear directly both upon the regulation of intraocular pressure and upon glaucoma.

Serum bank for biological markers for breast cancer

A bank of serum specimens from women at varying risks of breast cancer has been established. Panels of test specimens can be secured by qualified investigators to evaluate newly discovered biological markers for breast cancer, to verify preliminary data, and to compare performance of established assays among different laboratories. Panels consisting of coded 1-ml vials of sera will be sent upon request to approved investigators. The procedure for application for serum panels is described.

Ciliary epithelia of the mammalian eye in cultured explants

The ultrastructural characteristics of ciliary epithelium from bovine, pigmented rabbit, and fetal albino rabbit were studied in cultured explants. The tips of ciliary processes were cultured in plastic dishes with Dulbecco Modified Eagle Medium (DMEM) containing 5% fetal bovine serum. More than half of the explants adhered to the plastic culture dish, and epithelial cells spread as monolayers within a few days. Initially the explant contains two layers, the outer (nonpigmented cells) and the inner (pigmented cells). Later the explant exhibits three layers: 1) outermost lightly pigmented flattened cells, 2) an outer layer of non-pigmented cells, and 3) an inner layer of densely pigmented cuboidal cells. The cells of the outermost layer are continuous with the cells of the inner layer. A narrow space lies between the outermost layer and the outer layer. The columnar cells in the outer layer contain well developed organelles but no pigment granules; they possess a basement membrane, lateral interdigitations, and junctional complexes near their apices. Numerous focal junctions and some ciliary channel-like structures were detected between the columnar cells of the outer layer and the cuboidal cells of the inner layer. The cuboidal cells of the inner layer are filled with pigment granules. These observations suggest that the columnar cells of the outer layer are nonpigmented epithelium, the cuboidal cells of the inner layer are pigmented epithelium, and the flattened cells in the outermost layer are derived from pigmented epithelium.

Neurohypophyseal peptides and the eye: use of synthetic analogs in analyzing effects on the pupil

Effects of neurohypophyseal (NHP) and synthetic analogs on the pupil of the rabbit were explored. This was prompted by the recent emergence of synthetic analogs with selective agonist and antagonist properties. The miotic effect of the NHP was examined in an isolated iris preparation. Minimum concentrations of arginine-vasopressin (AVP) needed to cause threshold pupillary constriction were approximately 10(-10) M. The miotic potency of several NHP analogs correlated best with their pressor activity. In addition, the synthetic NHP pressor antagonist d(CH2)5 Tyr(Me)AVP specifically antagonized the miotic effect, confirming that a pressorlike receptor mediates this pharmacologic action of the NHP. We also employed the technique of in vivo intravitreal administration of pharmacologic doses of the NHP in the rabbit. Once again, potent miotic activity was demonstrated. The relative miotic potency of the NHP in vivo provided further support to the relationship between the NHP "pressor" receptor and pupillary constriction. We believe that the use of a variety of NHP natural and synthetic analogs may also prove helpful in investigating potential physiological effects of the NHP on other intraocular smooth muscle.