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One-day 'family survival' psychoeducation workshops are a promising, convenient method of disseminating basic information to families with a relative who is diagnosed with a serious mental illness such as schizophrenia, major depression, or other affective disorders. At five separate psychoeducation workshops, 83 participating families completed the self-report North-Sachar Family Life Questionnaire and open-ended 'problem lists' of issues facing the families both before and after the workshops. Outcomes consistently demonstrated positive change pre- to post-workshop. Issues reported by workshop participants included desire for education about illness, identification of resources, coping with the illness, and family relationships. The workshop model demonstrated consistent achievement of the outcomes measured, meeting short-term goals. Although models such as the family responsive approach reported in this article are not designed to create long-term gains for the family, they appear to benefit families and may help connect families with more intensive services to facilitate long-term change. [ABSTRACT FROM AUTHOR]

Heterobifunctional small molecule degraders are a subset of targeted protein degraders (TPDs), consisting of two ligands joined by a linker to induce proteasomal degradation of a target protein. As compared to traditional small molecules these compounds generally demonstrate inflated physicochemical properties, which may require innovative formulation strategies to enable their delivery and exert pharmacodynamic effect. The blood brain barrier (BBB) serves an essential function in human physiology, but its presence requires advanced approaches for treating central nervous system (CNS) diseases. By integrating emerging modalities like TPDs with conventional concepts of drug delivery, novel strategies to overcome the BBB can be developed. Amongst the available routes, lipid and polymer-based long-acting delivery seems to be the most amenable to TPDs, due to their ability to encapsulate lipophilic cargo and potential to be functionalized for targeted delivery. Another key consideration will be understanding E3 ligase expression in the different regions of the brain. Discovery of new brain or CNS disease specific E3 ligases could help overcome some of the barriers currently associated with CNS delivery of TPDs. This review discusses the current strategies that exist to overcome and improve therapeutic delivery of TPDs to the CNS., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Dry powder inhaler (DPI) products are commonly formulated as a mixture of micronized drug particles and large carrier particles, with or without additional fine particle excipients, followed by final powder filling into dose containment systems such as capsules, blisters, or reservoirs. DPI product manufacturing consists of a series of unit operations, including particle size reduction, blending, and filling. This review provides an overview of the relevant critical process parameters used for jet milling, high-shear blending, and dosator/drum capsule filling operations across commonly utilized instruments. Further, this review describes the recent achievements regarding the application of empirical and mechanistic models, especially discrete element method (DEM) simulation, in DPI process development. Although to date only limited modeling/simulation work has been accomplished, in the authors' perspective, process design and development are destined to be more modeling/simulation driven with the emphasis on evaluating the impact of material attributes/process parameters on process performance. The advancement of computational power is expected to enable modeling/simulation approaches to tackle more complex problems with better accuracy when dealing with real-world DPI process operations.

Developability molecule assessment is a key interfacial capability across the biopharmaceutical industry, screening and staging molecules discovered by medicinal chemists for successful chemistry manufacturing controls (CMC) development and launch. The breadth of responsibility and expertise such teams possess puts them in a unique position to understand the impact of the physicochemical properties of a drug during its initial discovery and subsequent development. However, most of the publications describing trends in physicochemical properties are written from a medicinal chemistry perspective with the aim to identify molecules with better ADMET profiles that are either lead-like or drug-like, failing to describe the impact these properties have on CMC development. To systematically uncover knowledge obtained from recent trends in physicochemical properties and the corresponding impact on CMC development, a comprehensive analysis was conducted on molecules in the drug repurposing hub dataset. The only physicochemical property that seems to have been preserved in FDA-approved oral molecules over the decades (1900-2020) is a constant H-bond donor count, highlighting the importance this property has on cell permeability and lattice energy. Pharmaceutical attrition analysis suggests that partition-distribution coefficient, H-bond acceptors, polar surface area and the fraction of sp 3 carbons are properties that are associated with compound attrition. Looking at pharmaceutical attrition asynchronously with the temporal analysis of FDA-approved oral molecules highlights the opposing trends, risks and diminishing effects some of these physiochemical properties (cLogP, cLogD and Fsp 3 ) have on describing compound attrition during the past decade. Trellising the dataset by target class suggests that certain formulation and drug delivery strategies can be anticipated or put into place based on target class of a molecule. For example, molecules binding to nuclear hormone receptors are amenable to lipid-based drug delivery systems with proven commercial success. Although the poor solubility of kinase inhibitors is a combination of hydrophobicity (due to aromaticity) required to bind to its target and high lattice energy (melting point), they are a challenging target class to formulate. The influence of drug targets on physicochemical properties and the temporal nature of these properties is highlighted when comparing molecules in the drug repurposing dataset to those developed at Amgen. An improved understanding of the impact of molecular properties on performance attributes can accelerate decisions and facilitate risk assessments during candidate selection and development., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Sustained-release formulations are important tools to convert efficacious molecules into therapeutic products. Hydrogels enable the rapid assessment of sustained-release strategies, which are important during preclinical development where drug quantities are limited and fast turnaround times are the norm. Most research in hydrogel-based drug delivery has focused around synthesizing new materials and polymers, with limited focus on structural characterization, technology developability and implementation. Two commercially available thermosensitive hydrogel systems, comprised of block copolymers of poly(lactic-co-glycolic acid)-b-poly(ethylene glycol)-b-poly(lactic-co-glycolic acid) (PLGA) and poly(lactide-co-caprolactone)-b-poly(ethyleneglycol)-b-poly(lactide-co-caprolactone) (PLCL), were evaluated during this study. The two block copolymers described in the study were successfully formulated to form hydrogels which delayed the release of lysozyme (> 20 days) in vitro. Characterization of formulation attributes of the hydrogels like T sol-gel temperature, complex viscosity and injection force showed that these systems are amenable to rapid implementation in preclinical studies. Understanding the structure of the gel network is critical to determine the factors controlling the release of therapeutics out of these gels. The structures were characterized via the gel mesh sizes, which were estimated using two orthogonal techniques: small angle X-ray scattering (SAXS) and rheology. The mesh sizes of these hydrogels were larger than the hydrodynamic radius (size) of lysozyme (drug), indicating that release through these gels is expected to be diffusive at all time scales rather than sub-diffusive. In vitro drug release experiments confirm that diffusion is the dominating mechanism for lysozyme release; with no contribution from degradation, erosion, relaxation, swelling of the polymer network or drug-polymer interactions. PLGA hydrogel was found to have a much higher complex viscosity than PLCL hydrogel, which correlates with the slower diffusivity and release of lysozyme seen from the PLGA hydrogel as compared to PLCL hydrogel. This is due to the increased frictional drag experienced by the lysozyme molecule in the PLGA hydrogel network, as described by the hydrodynamic theory., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Drug-delivery technologies for modified drug release have been in existence for decades, but their utilization has been largely limited to post-launch efforts improving therapeutic outcomes. Recently, they have gained renewed importance because the pharmaceutical industry is steadily shifting to a more integrated discovery-development approach. In discovery, modulating target engagement via drug-delivery technologies can enable crucial pharmacological studies for building well-defined criteria for molecular design. In development, earlier implementation of delivery technologies can enhance the value of drug products through reduced dosing frequency and improved tolerability and/or safety profile, thereby leading to better adherence and therapeutic effectiveness., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Early prediction of elimination pathways for new chemical entities can have a profound impact on drug discovery programs. The recently proposed Extended Clearance Classification System (ECCS) is a step in the right direction, providing a framework to help identify the major elimination pathway of a drug. A list of 42 Amgen small molecules was evaluated against the ECCS framework to assess its performance in retrospectively predicting their major elimination pathway. Here, we present a critical analysis of the chemical space defined by the ECCS framework with the aim of identifying its applicability and constraints. This evaluation highlights the critical need for periodic review and revision of ECCS, given that target constraints are moving molecules away from the traditional 'drug-like' physicochemical space., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The druggability and developability space is rapidly evolving in the post-genomic era. In the past, Lipinski's rule-of-five (Ro5) emerged and served as a guide for drug-like molecule design for oral delivery in the traditional druggable target space. In contrast, in this new era, a transition is occurring in drug discovery towards novel approaches to bind and modulate challenging biological targets that have led to transformative treatments for patients. Consequently, drugging novel targets using a variety of emerging molecular modalities, namely beyond the Ro5 (bRo5) small molecules (such as protein-protein interaction modulators, protein-targeted chimeras, or PROTACs), peptide/peptidomimetics, and nucleic acid-based modalities, have become a key focus in drug discovery. Herein, the emerging druggability and developability space is discussed side by side to build a general understanding of the potential development challenges of these novel modalities. An overview is provided on the evolving novel targets and molecular modalities, followed by a detailed analysis of the druggability aspects as well as the strategies used to progress drug candidate, and the trending chemistry and formulation strategies used to assess developability.

High levels of Pim expression have been implicated in several hematopoietic and solid tumor cancers, suggesting that inhibition of Pim signaling could provide patients with therapeutic benefit. Herein, we describe our progress towards this goal using a screening hit (rac-1) as a starting point. Modification of the indazole ring resulted in the discovery of a series of imidazopyridazine-based Pim inhibitors exemplified by compound 22m, which was found to be a subnanomolar inhibitor of the Pim-1 and Pim-2 isoforms (IC 50 values of 0.024nM and 0.095nM, respectively) and to potently inhibit the phosphorylation of BAD in a cell line that expresses high levels of all Pim isoforms, KMS-12-BM (IC 50 =28nM). Profiling of Pim-1 and Pim-2 expression levels in a panel of multiple myeloma cell lines and correlation of these data with the potency of compound 22m in a proliferation assay suggests that Pim-2 inhibition would be advantageous for this indication., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

In nonsmall cell lung cancer (NSCLC), the threonine(790)-methionine(790) (T790M) point mutation of EGFR kinase is one of the leading causes of acquired resistance to the first generation tyrosine kinase inhibitors (TKIs), such as gefitinib and erlotinib. Herein, we describe the optimization of a series of 7-oxopyrido[2,3-d]pyrimidinyl-derived irreversible inhibitors of EGFR kinase. This led to the discovery of compound 24 which potently inhibits gefitinib-resistant EGFR(L858R,T790M) with 100-fold selectivity over wild-type EGFR. Compound 24 displays strong antiproliferative activity against the H1975 nonsmall cell lung cancer cell line, the first line mutant HCC827 cell line, and promising antitumor activity in an EGFR(L858R,T790M) driven H1975 xenograft model sparing the side effects associated with the inhibition of wild-type EGFR.

Single-crystalline ceria nanorods were fabricated using a hydrothermal process and annealed at 325 °C-800 °C. As-synthesized CeO2 nanorods contain a high concentration of defects, such as oxygen vacancies and high lattice strains. Annealing resulted in an improved lattice crystalline quality along with the evolution of novel cavity-shaped defects in the nanorods with polyhedral morphologies and bound by e.g. {111} and {100} (internal) surfaces, confirmed for both air (ex situ) and vacuum (in situ) heating. We postulate that the cavities evolve via agglomeration of vacancies within the as-synthesized nanorods.

High levels of Pim expression have been implicated in several hematopoietic and solid tumor cancers. These findings suggest that inhibition of Pim signaling by a small molecule Pim-1,2 inhibitor could provide patients with therapeutic benefit. Herein, we describe our progress towards this goal starting from the highly Pim-selective indole-thiadiazole compound (1), which was derived from a nonselective hit identified in a high throughput screening campaign. Optimization of this compound's potency and its pharmacokinetic properties resulted in the discovery of compound 29. Cyclopropane 29 was found to exhibit excellent enzymatic potency on the Pim-1 and Pim-2 isoforms (Ki values of 0.55nM and 0.28nM, respectively), and found to inhibit the phosphorylation of BAD in the Pim-overexpressing KMS-12 cell line (IC50=150nM). This compound had moderate clearance and bioavailability in rat (CL=2.42L/kg/h; %F=24) and exhibited a dose-dependent inhibition of p-BAD in KMS-12 tumor pharmacodynamic (PD) model with an EC50 value of 6.74μM (18μg/mL) when dosed at 10, 30, 100 and 200mg/kg po in mice., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Zeneth is a new software application capable of predicting degradation products derived from small molecule active pharmaceutical ingredients. This study was aimed at understanding the current status of Zeneth's predictive capabilities and assessing gaps in predictivity. Using data from 27 small molecule drug substances from five pharmaceutical companies, the evolution of Zeneth predictions through knowledge base development since 2009 was evaluated. The experimentally observed degradation products from forced degradation, accelerated, and long-term stability studies were compared to Zeneth predictions. Steady progress in predictive performance was observed as the knowledge bases grew and were refined. Over the course of the development covered within this evaluation, the ability of Zeneth to predict experimentally observed degradants increased from 31% to 54%. In particular, gaps in predictivity were noted in the areas of epimerizations, N-dealkylation of N-alkylheteroaromatic compounds, photochemical decarboxylations, and electrocyclic reactions. The results of this study show that knowledge base development efforts have increased the ability of Zeneth to predict relevant degradation products and aid pharmaceutical research. This study has also provided valuable information to help guide further improvements to Zeneth and its knowledge base.

As of 2012, breast augmentation surgery continues to be the most commonly performed aesthetic surgical procedure in the United States. Surgeons consider a multitude of factors when choosing the type and style of breast implant for a patient. With the continuous evolution of breast implant designs, there are a variety of breast implant options for plastic surgeons to choose from; however, round implants remain the implant of choice for breast augmentation. This article discusses preoperative planning, implant selection, surgical techniques, and postoperative management using Sientra's Silimed brand smooth and textured round implants.

Invited for this month's cover is the group of Dr. Sudipta Seal from University of Central Florida, USA and a collaborator from the University of Kent, UK. The cover picture shows a morphological phase diagram of CeO 2 indicating regions of nanoparticle nanorods and nanocube formation after certain time periods of hydrothermal treatment. Read the full text of the article at page 1446., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

γ-Secretase modulators (GSMs) are potentially disease-modifying treatments for Alzheimer's disease. They selectively lower pathogenic Aβ42 levels by shifting the enzyme cleavage sites without inhibiting γ-secretase activity, possibly avoiding known adverse effects observed with complete inhibition of the enzyme complex. A cell-based HTS effort identified the sulfonamide 1 as a GSM lead. Lead optimization studies identified compound 25 with improved cell potency, PKDM properties, and it lowered Aβ42 levels in the cerebrospinal fluid (CSF) of Sprague-Dawley rats following oral administration. Further optimization of 25 to improve cellular potency is described., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Fly ash, a coal combustion byproduct with a predominantly aluminosilicate composition, is modified to develop an inexpensive sorbent for oil spill remediation. The as-produced fly ash is a hydrophilic material with poor sorption capacity. A simple two-step chemical modification process is designed to improve the oil sorption capacity. First, the fly ash was transformed to a zeolitic material via an alkali treatment, which increased the specific surface area up to 404 m(2) g(-1). Then, the material was surface functionalized to form a hydrophobic material with high contact angle up to 147° that floats on the surface of an oil-water mixture. The reported oil sorption capacities of X-type zeolite sorbent with different surface functionalization (propyl-, octyl-, octadecyl-trimethoxysilane and esterification) were estimated to 1.10, 1.02, 0.86, and 1.15 g g(-1), respectively. Oil sorption was about five times higher than the as-received fly ash (0.19 g g(-1)) and also had high buoyancy critical for economic cleanup of oil over water.

Compounds 1 (N1-(3-ethynylphenyl)-6-methyl-N5-(3-(6-(methylamino)pyrimidin-4-yl)pyridin-2-yl) isoquinoline-1,5-diamine) and 2 (N-(3-ethynylphenyl)-6,7-bis(2-methoxyethoxy)quinazolin-4-amine; Erlotinib/Tarceva) are kinase inhibitors that contain a terminal phenyl acetylene moiety. When incubated in the presence of P450 and NADPH, the anticipated phenyl acetic acid metabolite was formed. When 10 mM of N-acetyl-l-cysteine was added to the incubation mixtures, the phenyl acetic acid product was reduced and at 25 mM or higher concentration of NAC, formation of the phenyl acetic acid was abolished. Instead, the phenyl acetylene moiety lost a carbon and formed a benzaldehyde product. Other oxidation products incorporating one or more equivalents of NAC were also observed. The identities of the metabolites were characterized by MS and NMR. Addition of deferoxamine or ascorbic acid diminished the formation of the NAC influenced products. Similar products were also observed when 1 or 2 were incubated in P450 reactions supplemented with GSH, in Fenton reactions supplemented with NAC or GSH, and in peroxidase reactions supplemented with NAC. We propose the thiols act as a pro-oxidant readily undergoing a one-electron oxidation to form thiyl radicals which in turn initiates the formation of other peroxy radicals that drive the reaction to the observed products. These in vitro findings suggest that one-electron oxidation of thiols may promote the cooxidation of xenobiotic substrates.

Purpose: To study the role of unsaturated fatty acid ester substituents in the autoxidation of polysorbate 80 using quantitative kinetics., Methods: Oxidation kinetics were monitored at 40 degrees C in aqueous solution by tracking head space oxygen consumption using a fiber optic oxygen sensor with phase shift fluorescence detection. Radical chain initiation was controlled using an azo-initiator and assessed by Hammond's inhibitor approach, allowing oxidizability constants (k(p)/(2k(t))(1/2)) to be isolated. Reaction orders were determined using modified van't Hoff plots and mixed polysorbate micelles., Results: The oxidizability constant of polysorbate 80 ((1.07 +/- 0.19) x 10(-2) M(-1/2) s(-1/2)) was found to be 2.65 times greater than polysorbate 20 ((0.404 +/- 0.080) x 10(-2) M(-1/2) s(-1/2)). The additional reactivity of polysorbate 80 was isolated and was first-order in the unsaturated fatty acid ester substituents, indicating that the bulk of the autoxidative chain propagation is due to these groups. This data, and the observation of a half-order dependence on the azo-initiator, is consistent with the classical autoxidation rate law (-d[O(2)]/dt = k(p)[RH](R(i)/2k (t))(1/2))., Conclusions: Polysorbate 80 autoxidation follows the classical rate law and is largely dependent on the unsaturated fatty acid ester substituents. Clarification of the substituents' roles will aid formulators in the selection of appropriate polysorbates to minimize oxidative liabilities.

Finding formulations that prevent degradation of the active pharmaceutical ingredient is an essential part of drug development. One of the major mechanisms of degradation is oxidation. Oxidative degradation is complex, and can occur via different mechanisms, such as autoxidation, nucleophilic/electrophilic addition, and electron transfer reactions. This paper uses three model compounds and determines the mechanisms of oxidation and strategies to reduce degradation. The mechanism of oxidation was established by comparing the results of different forced degradation experiments (radical initiation and peroxide addition), computational chemistry to those of formulated drug product stability. The model compounds chosen contained both oxidizable amine and sulfide functional groups. Although, both oxidative forced degradation conditions showed different impurity profiles the peroxide results mirrored those of the actual stability results of the drug product. The major degradation pathway of all compounds tested was nucleophilic/electrophilic oxidation of the amine to form N-oxide. Strategies to prevent this oxidation were explored by performing forced degradation experiments of the active pharmaceutical ingredient (API) in solution, in slurries containing standard excipient mixtures, and in solid formulation blends prepared by wet granulation. The reaction was significantly influenced by pH in solvent and excipient slurries, with 100% degradation occurring at basic pH values (>pH 8) and no degradation occurring at pH 2 upon exposure to 0.3% peroxide. Wet granulated blends were also stabilized by lowering the pH during granulation through the addition of citric acid prior to the solution of peroxide, resulting in little (0.02% maximum) or no degradation for the four different blends after 6 week storage at 40 degrees C/75%RH.

Recent evidence has indicated that the prevalence of addiction in youth is far higher than previously expected. High demand for services to this population require attention to programs providing interventions, in particular to the regulations and structures that assure youth receive quality services. Thus, the current research examines state-level certification and program requirements for inpatient youth facilities. Current data (from August 2002 through July 2003) on state-level regulations was collected from a variety of sources. Wherever possible, confirmation was sought from multiple sources. Multiple authors interpreted information. Youth with addictions are currently being treated across a wide variety of governmental agencies. Level of detail and clarity of information varied widely, as did distinctness of youth requirements from adult ones. Adequate regulatory attention was evident in a minority of states, while a handful of states did little or nothing to distinguish youth from adult services. While it is undoubtedly the case that providers within each state offer outstanding services, there is often little or no available protection for these youth through governmental regulations. Attention is needed in almost all states to providing additional regulations and program requirements that assure youth consistency in service quality. Recommendations are made for standards of certification requirements.

Purpose: To show, using a model study, how electronic structure theory can be applied in combination with LC/UV/MS/MS for the prediction and identification of oxidative degradants., Methods: The benzyloxazole 1, was used to represent an active pharmaceutical ingredient for oxidative forced degradation studies. Bond dissociation energies (BDEs) calculated at the B3LYP/6-311+G(d,p)//B3LYP/6-31G(d) level with isodesmic corrections were used to predict sites of autoxidation. In addition, frontier molecular orbital (FMO) theory at the Hartree-Fock level was used to predict sites of peroxide oxidation and electron transfer. Compound 1 was then subjected to autoxidation and H2O2 forced degradation as well as formal stability conditions. Samples were analyzed by LC/UV/MS/MS and degradation products proposed., Results: The computational BDEs and FMO analysis of 1 was consistent with the LC/UV/MS/MS data and allowed for structural proposals, which were confirmed by LC/MS/NMR. The autoxidation conditions yielded a number of degradants not observed under peroxide degradation while formal stability conditions gave both peroxide and autoxidation degradants., Conclusions: Electronic structure methods were successfully applied in combination with LC/UV/MS/MS to predict degradation pathways and assist in spectral identification. The degradation and excipient stability studies highlight the importance of including both peroxide and autoxidation conditions in forced degradation studies.

The purpose of this study was to investigate collagen receptors on primary bovine articular chondrocytes from full-thickness and different layers of bovine articular cartilage. Cytometric studies with antibodies showed that approximately 56% of the chondrocytes from the superficial layer and 29% of the chondrocytes from the deep layer bound anti-annexin V. A similar tendency was found for alpha5 and beta1 integrin antibodies. Flow cytometric analysis initially detected annexin V on chondrocytes following isolation; the level of detection subsequently decreased by 24 hours, whereas that of alpha5 and beta1 integrins increased. Treatment of chondrocytes with collagenase at 24 hours restored the initially high epitope recognition of annexin V, indicating masking of annexin V by newly formed collagen matrix. There was little effect on detection levels for beta1 integrin. Contrary to the specific matrix receptor expression, chondrocytes from superficial and deep layers differed little in attachment to immobilized types I and II collagens. However, the attachment was more effectively inhibited with anti-annexin V than with integrin antibodies. Competition studies with preparations of soluble collagens revealed a preferential binding of bovine type-II collagen compared with bovine type-I collagen. Anti-annexin V antibodies inhibited binding of type-II collagen more effectively than anti-alpha5 or anti-beta1 integrin antibodies. Evidently, under the in vitro conditions of this study, annexin V is the quantitatively predominant type-II collagen receptor on bovine articular chondrocytes. This opens a discussion of the possibly dualistic metabolic/mechanical annexin V-integrin receptor elements.

Annexin V has been characterized as a major collagen type II binding cell-surface component of normal chondrocytes and is also called anchorin CII in chondrogenic populations. Herein we present evidence that in vitro cultured Swarm rat chondrosarcoma cells are not capable of binding collagen type II in significant quantities to their surfaces, as compared to normal rat chondrocytes. This finding coincides with a deficiency of annexin V on the surface of these cells. A small quantity of an intracellular polypeptide could be detected which is immunologically cross-reactive with annexin V but displayed a mobility in SDS-PAGE of less than 34 kD compared to the M(r) 36 kD of intact rat annexin V. By immunohistochemistry the protein could be localized in the cytoplasm of in vitro and in vivo grown tumor cells. By reverse transcription-polymerase chain reaction and Northern blot analysis, a regular-sized mRNA for annexin V could be detected in the chondrosarcoma cells that is expressed in only slightly lower quantities than in normal chondrocytes. Taken together, the data suggest a modified processing or turnover for annexin V in the chondrosarcoma excluding it from being a functionally active collagen type II binding protein. The findings support the hypothesis of cell-surface annexin V as a key component for the formation of the pericellular matrix of chondrocytes.

Fetal heart rate variability was derived from fetal magnetocardiogram recordings in ten subjects at gestation ages 32-38 weeks. Maternal interference was negligible and R-wave detection was highly reliable. Oscillations suggestive of respiratory sinus arrhythmia (RSA) were prominent in many of the heart rate tracings. Spectral analysis was used to quantify heart rate variability and to examine the influence of the RSA-like oscillations on heart rate variability. The oscillations were associated with increased power in the frequency range 0.4-1.0 Hz (P < or = 0.05). Magnetic recording appears to offer significant advantages for investigation of beat-to-beat fetal heart rate throughout the latter stages of pregnancy.

Objective: The differential vasoactive effects of hydralazine on the uteroplacental vascular bed were studied., Study Design: After control measurements were taken, near-term chronically prepared pregnant sheep were continuously infused with angiotensin II. Maternal arterial pressure was increased by 32 mm Hg. Hydralazine was then administered; the effects on regional resistance and blood flow were evaluated with a radionuclide-labeled microsphere technique. Analysis of variance for repeated measures was used to compare observations., Results: When compared with the hypertensive state, hydralazine caused the following changes by 40 minutes (mean +/- SEM): Although maternal blood pressure fell 31% +/- 5% (p = 0.0005), placental blood flow was unchanged, total uteroplacental blood flow increased 24% +/- 8% (p = 0.03), total uteroplacental resistance decreased 43% +/- 4% (p = 0.0002), placental resistance decreased 19% +/- 9% (p = 0.01), myoendometrial blood flow increased 390% +/- 82% (p = 0.0005), and myoendometrial resistance decreased 82% +/- 4% (p = 0.0005)., Conclusions: In angiotensin II-induced hypertensive ewes, hydralazine is an effective dilator of the uteroplacental vascular bed and can maintain placental blood flow while blood pressure.

Objective: We attempted to determine the relationship between the fetal heart rate power spectrum and fetal state., Study Design: Interbeat intervals, electrocortical activity, and fetal breathing movements were recorded from five near-term fetal lambs. Interbeat intervals were taken from epochs of low-voltage electrocortical activity with breathing, low-voltage electrocortical activity without breathing, and high-voltage electrocortical activity without breathing. Power spectral techniques were applied to determine the underlying frequencies contributing to fetal heart rate variability. Spectral analysis was also performed on fetal breathing data from three animals., Results: Significant differences were found between low-voltage electrocortical activity with breathing and high-voltage electrocortical activity without breathing at 0.62 Hz and from 1.09 to 1.56 Hz. There was no clear relationship between the breathing and heart rate spectra., Conclusions: Fetal heart rate is mediated by both state and respiratory variables. The respiratory component is not strictly related to respiratory rate.

Objective: Our purpose was to test the effects of terbutaline on uterine electric and contractile responses to prostaglandin E2., Study Design: In five late-gestation ewes, prostaglandin E2 (22.9 +/- 2.3 micrograms/min for 3 minutes) was given twice at 30-minute intervals during control. Terbutaline sulfate (2 micrograms/min) was then infused for 30 minutes. Prostaglandin E2 challenge was repeated 10 minutes after the onset of terbutaline infusion and thereafter at 30-minute intervals. Two-way analysis of variance for repeated measures revealed a significant main effect for time (p less than or equal to 0.0001) and between time and response (p less than or equal to 0.05)., Results: Both electric (p less than or equal to 0.0001) and intrauterine pressure (p less than or equal to 0.0001) responses were suppressed during terbutaline. The influence on intrauterine pressure persisted 10 minutes after terbutaline (p less than or equal to 0.01) while the electric response was not different from control., Conclusions: Terbutaline initially diminishes both uterine contractile and electric activity, but electric recovery precedes contractile recovery.

To test the hypothesis that fetal lambs are able to maintain oxygen delivery to myocardial, brain and adrenal tissues during reduction in uterine blood flow to 25% of control, we performed experiments on five ewes and their fetuses. A snare occluder was placed around the maternal common hypogastric artery and catheters were placed for measurement of blood pressures, flows, blood gas tensions, pH and oxygen content. After a five day recovery period, control measurements were made. The snare occluder was then closed until the artery was fully occluded. The arterial occlusion caused uteroplacental blood flow to fall to 32 +/- 4% and maternal placental blood flow to fall to 25 +/- 3% of control values. This level of asphyxia was maintained for 19 +/- 3 minutes, when maternal and fetal blood flows were measured again. In response to occlusion, fetal ascending aortic PO2 fell from 21 +/- 2 (SEM) to 13 +/- 2 mmHg (P less than or equal to 0.01), oxygen content from 4.3 +/- 0.3 to 1.4 +/- 0.2 mM (P less than or equal to 0.01) and pH from 7.37 +/- 0.01 to 7.21 +/- 0.05 (P less than or equal to 0.01). PCO2 rose from 48 +/- 1 to 62 +/- 3 mmHg (P less than or equal to 0.01). Fetal arterial blood pressure increased from 51 +/- 3 to 61 +/- 3 mmHg (P less than or equal to 0.001) and heart rate decreased from 172 +/- 10 to 104 +/- 4 beats.min-1 (P less than or equal to 0.01). The heart, brain and adrenals showed vasodilation in response to the asphyxic stimulus.(ABSTRACT TRUNCATED AT 250 WORDS)

Pressure-flow relationships in the ventilated lung have not been previously determined in undelivered fetal sheep. Therefore we studied 11 late-gestation chronically prepared fetal sheep during positive-pressure ventilation with different gas mixtures to determine the roles of mechanical distension and blood gas tensions on pressure-flow relationships in the lung. Ventilation with 3% O2-7% CO2 produced a substantial fall in pulmonary vascular resistance even though arterial blood gases were not changed. Increases in pulmonary arterial PO2 during ventilation were associated with falls in pulmonary vascular resistance beyond that measured during mechanical distension. Decreases in pulmonary arterial PCO2 and associated increases in pH were also associated with falls in pulmonary vascular resistance. Pulmonary blood flow ceased at a pulmonary arterial pressure that exceeded left atrial pressure, indicating that left atrial pressure does not represent the true downstream component of driving pressure through the pulmonary vascular bed. The slope of the driving pressure-flow relationship in the normal mature fetal lamb was therefore different from the ratio of pulmonary arterial pressure to pulmonary arterial flow. We conclude that mechanical ventilation, increased PO2 and decreased PCO2, and/or increased pH has an important influence on the fall in pulmonary vascular resistance elicited by positive pressure in utero ventilation of the fetal lamb and that the downstream driving pressure for pulmonary blood flow exceeds left atrial pressure.

Dawes (1986) has stated that, "The difference between high and low voltage activity depends solely on the presence in the latter of higher amplitude oscillations with relatively low frequency superimposed on the low voltage components as shown by spectral analysis". We have tested the constancy of the high frequency section of the power spectrum of the electrocorticogram in 7 near-term sheep fetuses. Under sterile conditions we implanted biparietal electrodes in the dura and a ground lead subcutaneously on the scalp. Five days after the surgery, with the animal standing quietly in the laboratory, we acquired the fetal electrocorticograms. Data were acquired during several high and low voltage electrocorticographic cycles in each animal. Two hundred power spectra were obtained during high and low voltage fetal electrocortical activity and statistically analyzed by paired t-test to discern differences in power between the high and low voltage pattern at each frequency (n = 7). We found that at all frequencies between 4 and 12 cycles/s the high voltage electrocorticogram had significantly more power than the low voltage electrocorticogram (P less than 0.05). This is in accordance with the established literature. We also observed that from 17 through 24 cycles/s the low voltage electrocorticogram is significantly higher than the high voltage electrocorticogram (P less than 0.05). In this frequency range the power of the high voltage expressed as a percentage of the power of the low voltage were respectively, 80, 74, 71, 66, 64, 64, 67, 64. These differences are of considerable magnitude and may be physiologically important.

We have reported in a previous study that adenosine infusion causes fetal placental vascular resistance to increase after 2 min. To determine whether this action is followed by a more prolonged vasodilation, we studied 7 mature fetal lambs. At surgery, catheters were inserted into the fetal hindlimb arteries and veins. After a five day recovery period, control blood flow measurements were made by radiolabeled microsphere technique immediately after an infusion of 0.9% NaCl, (vehicle, 1.03 ml.min-1) into a fetal vein for 2 min. Within 5 min of the control blood flow measurement, adenosine (10 mg/min) was infused for 2 min. Blood flow measurements were repeated 5, 10, 15, 20 and 30 min after the end of the infusion period. Fetal arterial blood pressure dropped from 50 +/- 1 to 34 +/- 5 mmHg immediately after the adenosine infusion and returned to the control value within 5 min after the infusion. No further blood pressure response was detected. However, placental vascular resistance fell from 0.334 +/- 0.040 to 0.269 +/- 0.027 (P less than 0.05) at the 15 min measurement, remained low through the 20 min measurement (P less than 0.001) and was not different from control levels 30 min after the adenosine infusion. We conclude that the fetal placental vasculature responds to systemic adenosine infusion in a biphasic manner. The immediate reaction to adenosine is a transient vasoconstriction in the fetal placental vasculature followed by vasodilation 15 to 20 min after the initial exposure to adenosine.

In late pregnancy the electrocortical activity (ECoG) in the ovine fetus starts to cycle between high and low voltage states. During the high voltage states of this activity fetal regional blood flows are decreased, and heart rate and fetal arterial blood pressure are both increased. Jensen et al. (1986) have postulated that these changes may be mediated by changes in autonomic tone. To test this hypothesis we placed catheters in 6 near-term sheep fetuses (gestational age = 128 days) and implanted electrodes to measure electrocortical activity. Five days after the surgery, fetal arterial blood was withdrawn during the first 3-5 min of each high and low voltage ECoG for 5 full cycles in each fetus. Plasma samples were analyzed for epinephrine, norepinephrine, and dopamine. Dopamine levels were not different in high and low voltage electrocortical state. In the high voltage ECoG state, epinephrine levels were 75 +/- 7 pg/ml and fell to 34 +/- 4 pg/ml during low voltage ECoG (P less than 0.01). During the high voltage state plasma norepinephrine was 623 +/- 85 pg/ml and fell during the low voltage period to 462 +/- 99 pg/ml (P less than 0.01). These data demonstrate that in the near-term sheep fetus plasma catecholamine levels fluctuate with ECoG state.

A wide variety of complications of the anophthalmic socket develop in patients after enucleation, including enophthalmos, superior sulcus deformities, eyelid malpositions, implant migration and extrusion, poor prosthetic motility, and socket contraction. Changes in the orbital blood flow and metabolic activity of the socket tissues and atrophy of the orbital fat occurring after enucleation have been suggested as two theoretical mechanisms that result in the development of these clinical conditions. Lack of scientific evidence and a limited understanding of the pathophysiologic basis of the features of anophthalmos led us to evaluate the validity of these proposed mechanisms in an animal model. Selected parameters of the normal orbits were compared with the contralateral anophthalmic orbits at different time intervals after surgery. Orbital blood flow was studied with selective ophthalmic artery angiography and radioactive microsphere techniques. Ophthalmic arteriography demonstrated symmetric caliber and filling characteristics of the major orbital vessels of the control and experimental orbits, although their topographic course was slightly more tortuous in the anophthalmic socket. Results of radioactive microsphere analysis of capillary blood flow per weight of the different orbital tissue compartments of the animals in the long-term group showed no significant difference between the normal and anophthalmic sockets. These findings provide evidence that the circulation dynamics and blood flow to orbital tissues do not change after enucleation surgery.

The pathophysiologic mechanisms responsible for the clinical features of the anophthalmic socket are poorly understood. Atrophy of orbital fat has been thought to be a major contributing cause of enophthalmos and the superior sulcus deformities that develop after enucleation, but it has never been demonstrated histopathologically or confirmed by scientific analysis. This study was undertaken to investigate the changes that occur in the orbital fat compartment of the anophthalmic socket in an animal model by measuring orbital soft tissue mass and evaluating adipocyte cell size. Instead of reduction in the tissue mass, a statistically significant greater weight of the fat and connective tissue compartment was found in the anophthalmic orbit by nearly 13% compared to the control orbit in the animals in the long-term group. No significant change in the mean maximal diameter of adipocytes developed 7 months after enucleation. These analyses do not support the concept that orbital fat atrophy or a reduction of metabolic activity occurs in the anophthalmic socket in this animal model. From these results and our previous findings that the circulation dynamics and blood flow to orbital tissues do not change after enucleation, we propose that the pathophysiologic basis of the problems associated with anophthalmos is a disturbance in the spatial architecture and interrelationships of the multiple tissue components of the orbit, not a change in the orbital blood flow or development of fat atrophy.

The time related hemodynamic responses to forskolin-elicited increases in cAMP were studied in the near-term fetus. Catheters and electrodes were inserted into 6 fetal sheep to measure arterial, venous and thoracic pressures, electrocorticogram, and electrocardiogram. At gestational day 134, experiments were performed to determine the effect of forskolin infusion (400 micrograms/ml at 1.03 ml/min for 5 min) on fetal blood pressure, coronary and cerebral blood flow and resistance. Blood flow measurements were made using 15 microns microspheres labelled with radioactive isotopes during the control period and at 0, 5, 10, 15, and 45 min after forskolin infusion. Forskolin infusion was always initiated during a high-voltage electrocortical epoch and was given twice in each animal. In each case, forskolin caused electrocortical activity to change from high-voltage state to an intermediate voltage state. Blood pressure fell significantly by the end of the infusion period and returned to control levels 10 min later. Fetal heart rate and coronary blood flow were immediately elevated by forskolin (P less than 0.01) whereas cerebral blood flow did not increase until 5 min later (P less than 0.01). Cerebral blood flow was still elevated (P less than 0.05) 45 min after the end of forskolin infusion, whereas coronary blood flow had returned to control levels. Both cerebral and coronary vascular resistance fell significantly in response to forskolin infusion (P less than 0.01). This effect lasted at least 15 min and had returned to control levels 45 min after forskolin had been terminated.

Local interaction of maternal and fetal placental blood flows was studied in two groups of unanaesthetized near-term sheep. Five sheep were exposed to a simulated dive to 100 feet of seawater (4.03 atmospheres) for 25 min. Six fetuses received an infusion of noradrenaline (6.8 micrograms/[kg x min]). Radioactive microspheres were administered simultaneously to mother and fetus before (control) and after (test) the experimental manipulation. Maternal and fetal relative activities, defined as % of total placental radioactivity divided by % of total placental weight, were calculated for 1-g pieces of cotyledonary tissue under control and test conditions. Pieces of cotyledons were defined as matched if the direction of change in relative activity from control to test was the same for mother and fetus. In the absence of an interaction between the maternal and fetal placental circulations, the probability of a piece of cotyledon being matched is 0.5. In each series of experiments the proportion of all cotyledon pieces having maternal and fetal relative activities that changed in the same direction was significantly greater than 0.5. Thus, the majority of the placental mass responds to a physical or chemical perturbation of the fetus in such a way that changes in relative perfusion are qualitatively matched in the adjacent maternal and fetal placental circulations.