Factors associated with increased risk of postoperative blood transfusion in patients undergoing total hip arthroplasty at an Irish University Hospital

INTRODUCTION

Approximately 7000 total hip arthroplasty (THA) surgeries occur in Ireland each year. A number of preoperative factors have been identified that increase the risk of postoperative blood transfusion after THA, including anaemia. The ability to identify patients at risk may allow preoperative management strategies to reduce blood transfusions. Data from Irish orthopaedic patients is currently lacking.

AIM

To investigate if preoperative anaemia and other factors are associated with postoperative blood transfusions in patients who undergo THA.

METHODS

A retrospective cohort study of all patients who underwent THA in 2019 in SIVUH, Cork, using medical chart review.

RESULTS

In total, 350 charts met the inclusion criteria, with 291 charts reviewed. 8.9% of the patients who underwent THA had preoperative anaemia. Among these, 19.2% had a postoperative blood transfusion, compared to 1.5% of patients who were not anaemic preoperatively. The odds of receiving a blood transfusion was 15.5 times greater in the preoperative anaemia group compared to the non-anaemic group. Increasing age and higher ASA scores were associated with preoperative anaemia and postoperative blood transfusions. Length of stay was increased by 2.2 days (p < 0.00016) if blood transfusion was required.

CONCLUSION

Preoperative anaemia was common in an Irish orthopaedic population undergoing THA. Preoperative anaemia predisposes patients to the greatest increased risk of postoperative blood transfusions. The other factors associated with the need for postoperative transfusion were ASA grade 3 or more and age greater than 65 years. Patients who received postoperative blood transfusions had a significantly increased length of hospital stay.

Abstract 2331: Loss of LRRC15 in osteosarcoma cells disrupts extracellular matrix integration, intercellular communication, and differentiation

Background: Leucine rich repeat containing 15 (LRRC15) is a 581 amino acid type 1 transmembrane protein that contains 15 leucine rich repeats. Cysteine clusters flank the LRR domain that functions as the collagen binding domain. LRRC15 has been found to be upregulated during osteogenic differentiation of mesenchymal stem cells, induced by TGFβ, and highly expressed in multiple solid tumors, notably in osteosarcoma (1). Antibody drug conjugates targeting LRRC15 have shown promising activity in pre-clinical studies (2).

Results: To investigate the function of LRRC15 in the osteosarcoma microenvironment, we generated inducible shRNA knockdown (KD) derivatives targeting 3’UTR and ORF regions of LRRC15 of four osteosarcoma cell lines. Using these models, we characterized the biological properties of LRRC15 knockdown under 2-D and 3-D growth conditions. We found that LRRC15 KD in 2-D culture resulted in reduced adhesion to extracellular matrix (ECM) components and impaired cell migration. In 3-D spheroid culture, LRRC15 KD severely impacted scaffold-free spheroid compaction and invasion of spheroids embedded in Matrigel. Dysregulation of multiple ECM, cell adhesion and communication pathways were revealed by transcriptomic analysis from samples collected at time points during the LRRC15 KD. Of interest, several key transcription factors including RUNX2, CTNNB1, and SP7 were downregulated in LRRC15 deficient cells.

Conclusion: Our comprehensive results establish the importance of LRRC15 as a critical cell-adhesion molecule essential for the maintenance of the osteogenic intercellular communication, invasion and differentiation revealing novel aspects of osteosarcoma cell-biology.

Reference:1.Purcell JW, Tanlimco SG, Hickson J, Fox M, Sho M, Durkin L, et al. LRRC15 Is a Novel Mesenchymal Protein and Stromal Target for Antibody-Drug Conjugates. Cancer Res 2018;78:4059-4072.2.Slemmons KK, Mukherjee S, Meltzer P, Purcell JW, Helman LJ. LRRC15 antibody-drug conjugates show promise as osteosarcoma therapeutics in preclinical studies. Pediatr Blood Cancer 2020:e28771.

Citation Format: Sanjit Mukherjee, Ankit Jajoo, Jack Zhu, Marbin Pineda, Robert Walker, James Purcell, Lee J Helman, Paul S. Meltzer. Loss of LRRC15 in osteosarcoma cells disrupts extracellular matrix integration, intercellular communication, and differentiation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2331.

Protein Tyrosine Kinase 7 (PTK7) Promotes Metastasis in Hepatocellular Carcinoma via SOX9 Regulation and TGF-β Signaling

BACKGROUND & AIMS

Metastasis is found in most advanced hepatocellular carcinoma (HCC) patients, and it drives tumor recurrence and systemic failure. There is no effective treatment owing to its complex biological features. Many of the molecular drivers of metastasis are crucial players in normal physiology but behave unconventionally during cancer progression. Targeting these molecular drivers for therapy and differentiating them from a physiological background require a detailed examination of the novel mechanisms involved in their activation during metastasis.

METHODS

Publicly available transcriptomic data such as that of TCGA-LIHC and Gene Expression Omnibus were utilized to identify novel targets upregulated in advanced and metastatic HCC. Validation of candidates was assisted by immunohistochemistry performed on tissue microarrays derived from more than 100 HCC patients. Expression of protein tyrosine kinase 7 (PTK7) was studied under the treatment of transforming growth factor-β1 and knockdown of SRY-Box Transcription Factor 9 (SOX9) to delineate upstream regulation, while CRISPR-mediated knockout and lentiviral overexpression of PTK7 in HCC cells were performed to study their functional and signaling consequences. Manipulated HCC cells were injected into mice models either by orthotopic or tail-vein injection to observe for any in vivo pro-metastatic effects.

RESULTS

PTK7 was discovered to be the kinase most significantly upregulated in advanced and metastatic HCC, at both transcriptomic and proteomic level. Bioinformatic analyses and functional assays performed in HCC cell lines revealed transforming growth factor-β signaling and SOX9 to be important activators of PTK7 expression. Functionally, enrichment of PTK7 expression could positively regulate metastatic potential of HCC cells in vitro and in lung metastasis models performed in immunodeficient mice. The up-regulation of PTK7 recruited the epithelial-mesenchymal transition components, zinc finger protein SNAI2 (SLUG) and zinc finger E-box-binding homeobox 1 (ZEB1).

CONCLUSIONS

Our study proposes PTK7 as a novel molecular driver in metastatic HCC, particularly in a transforming growth factor-β-activated microenvironment. The preferential expression of PTK7 resulted in a previously unobserved regulatory effect on the recruitment of epithelial-mesenchymal transition components, which established PTK7 as a potential determinant of specific epithelial-mesenchymal transition status. Therefore, our data support the continual development of PTK7-targeted agents as antimetastatic therapies.

Roles of Phytoestrogen in the Pathophysiology of Intracranial Aneurysm

[Figure: see text].

Neutrophil Extracellular Traps Promote the Development of Intracranial Aneurysm Rupture

[Figure: see text].

Abstract MP55: Endothelial Sirtuin-1 Deficiency Promotes the Rupture of Intracranial Aneurysm

Background: Sirtuin-1 is highly expressed in vascular tissues and plays an important role in numerous metabolic and inflammatory processes. Age-related reduction in Sirtuin-1 expression has been linked to chronic vascular inflammation and senescence, and may explain the increased risk of aneurysm rupture seen in the elderly population. Our previous study showed that pharmacological inhibition of Sirtuin-1 increases the rate of aneurysm rupture. This suggests that Sirtuin-1 protects against the rupture of intracranial aneurysm. However, the cell type responsible for this effect has not been determined.

Hypothesis: We hypothesize that reduced expression of Sirtuin-1 in endothelial cells promotes the rupture of intracranial aneurysm.

Methods: We induced intracranial aneurysms in mice by combining systemic hypertension and a single injection of elastase into the cerebrospinal fluid. We induced aneurysms in tamoxifen-inducible vascular smooth muscle cell-specific Sirtuin-1 knockout mice (SIRT1 f/f MYH11 ER-Cre+ ) and in endothelial cell-specific Sirtuin-1 knockout mice and their littermates (SIRT1 f/f Tie2 Cre+ , SIRT1 f/f Tie2 Cre- ). We used the rate of aneurysm rupture as the primary endpoint.

Results: Smooth muscle cell-specific Sirtuin-1 knockout had no effect on rate of aneurysm rupture. In contrast, SIRT1 f/f Tie2 Cre+ mice experienced a significantly increased rate of aneurysm rupture (SIRT1 f/f Tie2 Cre+ vs. SIRT1 f/f Tie2 Cre- : 86% vs. 42%, P < 0.05).

Conclusions: Our findings suggest that Sirtuin-1 expressed in the endothelium, but not in smooth muscle cells, protects against the rupture of intracranial aneurysm. As Tie2 is also expressed in hematopoietic cells, we are conducting experiments using SIRT1 f/f LysM Cre+ mice to exclude potential contributions of hematopoietic Sirtuin-1 to the observed effects. Endothelial Sirtuin-1 may be used as a therapeutic target for preventing the rupture of intracranial aneurysm.

LRRC15 Targeting in Soft-Tissue Sarcomas: Biological and Clinical Implications

BACKGROUND

LRRC15 is a member of the LRR (leucine-rich repeat) superfamily present on tumor-associated fibroblasts (CAFs) and stromal cells. The expression of LRRC15 is upregulated by the pro-inflammatory cytokine TGFβ. ABBV-085 is a monomethyl auristatin E (MMAE)-containing antibody-drug conjugate (ADC) designed to target LRRC15, and which has shown significant anti-tumor activity in several tumor models. This is the first focused examination of LRRC15 expression and ABBV-085 activity in soft-tissue sarcomas (STS).

METHODS

We analyzed the LRRC15 expression profile by immunohistochemistry in 711 STS cases, covering a broad spectrum of STS histologies and sub-classifications. In vivo experiments were carried out by using LRRC15-positive and LRRC15-negative patient-derived xenograft (PDX) models of STS.

RESULTS

In contrast to patterns observed in epithelial tumors, LRRC15 was expressed not only by stromal cells but also by cancer cells in multiple subsets of STS with significant variations noted between histological subtypes. Overexpression of LRRC15 is positively correlated with grade and independently associated with adverse outcome. ABBV-085 has robust preclinical efficacy against LRRC15 positive STS patient-derived xenograft (PDX) models.

CONCLUSION

We provide the first preclinical evidence that LRRC15 targeting with an antibody-drug conjugate is a promising strategy in LRRC15-positive STS. ABBV-085 is being evaluated in an ongoing clinical trial in STS and other malignancies.

Abstract 144: Roles of Aging and Cellular Senescence in Intracranial Aneurysm Rupture

Background: Aging is an independent risk factor for the rupture of intracranial aneurysm. One of the hallmarks of aging is chronic tissue inflammation. Sirtuin-1 keeps inflammation in check through the deacetylation of various proteins. It is well known that the levels of Sirtuin-1 in vascular tissues decrease with aging, resulting in chronic vascular inflammation. Age-dependent decrease in Sirtuin-1 may explain the link between aging and increased risk for aneurysmal rupture.

Hypothesis: Reduction of Sirtuin-1 promotes aneurysmal rupture by inducing sustained aneurysmal wall inflammation.

Methods: First, we assessed the levels of Sirtuin-1 expression in intracranial aneurysm tissues from patients older than 70 y.o. and compared with those from the younger patients (40 to 50 y.o.). Second, using a mouse model, we tested effects of Sirtuin-1 specific activator SRT1720 (15mg/kg/day) and specific inhibitor EX-527 (2.5mg/kg/day) on the development of aneurysmal rupture. In addition, we assessed the mRNA expression of inflammatory cytokines (IL-6, IL-1beta, MCP-1, and MMP-9) in cerebral arteries and aneurysms in mice treated with vehicle, SRT1720, or EX-527.

Results: Sirtuin-1 expression levels in intracranial aneurysm tissues from the older patients were lower than those from the younger patients. The pharmacological inhibition of Sirtuin-1 increased rupture rate in mice (vehicle vs. EX-527: 58% vs. 88%, P <0.05). Moreover, the pharmacological activation of Sirtuin-1 reduced rupture rate in mice (vehicle vs. SRT1720: 80% vs. 50%, P <0.05). Levels of IL-6, MMP-9 mRNAs in cerebral arteries were significantly higher in the inhibitor group than in the vehicle group. On the other hand, both mRNA levels were lower in the activator group than in the vehicle group.

Conclusions: Our findings suggest that the reduction of Sirtuin-1 promotes aneurysmal rupture via the induction of inflammation. This may explain the increased risk for aneurysmal subarachnoid hemorrhage in the older population. Our findings may become a basis for future studies to develop new therapies that target Sirtuin-1 for the prevention of aneurysmal rupture, especially in older patients.

First-in-human phase 1 study of ABBV-085, an antibody-drug conjugate (ADC) targeting LRRC15, in sarcomas and other advanced solid tumors

3004

Background: ABBV-085 is an ADC (conjugated to monomethyl auristatin E, drug:antibody ratio of 2:1) directed against leucine-rich repeat containing 15 (LRRC15), a type 1 transmembrane protein highly expressed on the surface of sarcomas and cancer-associated fibroblasts in stroma of many other cancers. ABBV-085 induced antitumor activity in both in vitro and xenograft models of sarcoma. This phase 1, first-in-human, 2-part study assessed the safety/tolerability of ABBV-085 in patients (pts) with advanced solid tumors (NCT02565758). Methods: Eligible pts (≥18 yr; advanced solid tumors) received ABBV-085 intravenously in a 3+3 dose-escalation (DE) design; 0.3- to 4.8-mg/kg doses every 2 wk (8 cohorts). Pharmacokinetics (PK) were assessed in cycle 1 and cycle 3. Results: As of Dec 2018, 78 pts were enrolled in monotherapy DE and dose-expansion (EXP) cohorts (≤2.7 mg/kg, n = 21; 3.6 mg/kg, n = 45; 4.2 mg/kg, n = 6; 4.8 mg/kg, n = 6); median age: 58 yr (range 21–84); median treatment (Tx) duration: 6.2 wk (range 0.3–54.4). Overall, 77 (98.7%) pts reported ≥1 Tx-emergent adverse events (TEAEs). Fatigue (48.7%) was most common; 19 (24.4%) pts reported grade 1/2 blurred vision (reversible on study discontinuation). Grade ≥3 TEAEs were reported in 56 (71.8%) pts; anemia (14.1%) was the most common. Dose-limiting toxicities occurred at 3.6 mg/kg (n = 1; anemia), 4.2 mg/kg (n = 1; hypertriglyceridemia), and 4.8 mg/kg (n = 2; ileus and nausea); 3.6 mg/kg was chosen as the recommended phase 1b dose (RP1bD). PK exhibited dose-proportional increase in the area under the curve after single-dose administration; half-life was 2.84 days at the RP1bD. Of the 27 sarcoma pts (DE [n = 8]/EXP [n = 19] cohorts; undifferentiated pleomorphic sarcoma [n = 10], osteosarcoma [n = 10], and other sarcomas [n = 7]) treated at the RP1bD, 4 (14.8%) had confirmed partial response (PR; 2 [7.4%] unconfirmed), 8 (29.6%) had stable disease, 11 (40.7%) had progressive disease; 2 (7.4%) were not evaluable. The median duration of response (confirmed responders) was 7.6 mo (95% CI: 5.6–9.2). Updated safety and efficacy data will be reported. Conclusions: ABBV-085 was well tolerated with durable PR observed in pts with advanced sarcomas. Clinical trial information: NCT02565758.

Evidence of soft dipole resonance in ^{11}li with isoscalar character

The first conclusive evidence of a dipole resonance in ^{11}Li having isoscalar character observed from inelastic scattering with a novel solid deuteron target is reported. The experiment was performed at the newly commissioned IRIS facility at TRIUMF. The results show a resonance peak at an excitation energy of 1.03±0.03 MeV with a width of 0.51±0.11 MeV (FWHM). The angular distribution is consistent with a dipole excitation in the distorted-wave Born approximation framework. The observed resonance energy together with shell model calculations show the first signature that the monopole tensor interaction is important in ^{11}Li. The first ab initio calculations in the coupled cluster framework are also presented.

Abstract 1770: Enavatuzumab (PDL192), a humanized monoclonal antibody to TweakR, displays broad anticancer activity which is dependent on NFκB signaling

TWEAK (TNFSF12) is a multifunctional cytokine that binds to the cell surface receptor TweakR (Fn14, TNFRSR12A). TweakR is overexpressed in many solid tumor types, including cancers of breast, pancreatic, and ovarian origin. The initial functional description of TWEAK described it as a weak inducer of apoptosis in certain cancer cell lines. TWEAK is also known to function in other diverse biological processes such as inflammation, tissue repair, angiogenesis, cell migration, and growth inhibition. The growth inhibitory activity of TWEAK observed in some cancer cell lines and the overexpression of its receptor in cancer led to investigation of targeting TweakR as a therapeutic modality. Enavatuzumab (PDL192), a humanized IgG1 mAb to TweakR, exhibits some of the same functional activities of TWEAK and is currently in clinical investigation for the treatment of solid tumors due to its significant in vitro and in vivo growth inhibitory activity in models of multiple solid tumor types.

The purpose of the current study was to provide insight into the mechanism of action of enavatuzumab and to further our understanding of the biology of TweakR in tumor cell lines. A panel of 106 cancer cell lines was tested for the ability of enavatuzumab to inhibit in vitro cell growth to identify characteristics of response. Of the 106 cell lines tested, 33 cell lines had &gt;25% growth inhibition in response to the drug. Using luciferase transcriptional reporter constructs, it was revealed that the NFκB pathway was activated in response to enavatuzumab treatment in responder cells. Both classical (p50/p65) and non-classical NFκB (p52/RelB) pathways were subsequently shown to be induced by enavatuzumab treatment using Western blot and functional ELISA in responder cell lines. Using Affymetrix™ microarrays, we observed that cell lines sensitive to enavatuzumab had a higher number of transcriptional changes compared with resistant cells and included many genes known to be regulated by NFκB. To confirm a role for NFκB in enavatuzumab-mediated signaling, we inhibited NFκB pathway induction using siRNAs to the individual NFκB subunits p50, p65, p52, and RelB as well as the upstream kinases IKKα and IKKβ. The siRNAs were able to block enavatuzumab's growth inhibitory activity in multiple sensitive cell lines. Further confirmation of the importance of NFκB was obtained using a small molecule inhibitor of IKKα/β (IKK16) which significantly reduced the drug-induced growth inhibition. The finding that NFκB drives the growth inhibitory activity of enavatuzumab is a compelling function for a family of transcription factors that are more frequently associated with cancer growth and survival than inhibition of cell proliferation.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1770. doi:10.1158/1538-7445.AM2011-1770

The expression and impact of antifungal grooming in ants

Parasites can cause extensive damage to animal societies in which many related individuals frequently interact. In response, social animals have evolved diverse individual and collective defences. Here, we measured the expression and efficiency of self-grooming and allo-grooming when workers of the ant Formica selysi were contaminated with spores of the fungal entomopathogen Metarhizium anisopliae. The amount of self-grooming increased in the presence of fungal spores, which shows that the ants are able to detect the risk of infection. In contrast, the amount of allo-grooming did not depend on fungal contamination. Workers groomed all nestmate workers that were re-introduced into their groups. The amount of allo-grooming towards noncontaminated individuals was higher when the group had been previously exposed to the pathogen. Allo-grooming decreased the number of fungal spores on the surface of contaminated workers, but did not prevent infection in the conditions tested (high dose of spores and late allo-grooming). The rate of disease transmission to groomers and other nestmates was extremely low. The systematic allo-grooming of all individuals returning to the colony, be they contaminated or not, is probably a simple but robust prophylactic defence preventing the spread of fungal diseases in insect societies.

Mixed mould species in laboratory cultures of respiratory specimens: how should they be reported, and what are the indications for susceptibility testing?

AIMS

To investigate how clinical microbiology laboratories should report and interpret mixed mould isolates including Aspergillus species from clinical samples and the criteria for susceptibility testing of the isolates.

METHODS

Retrospectively collected data from our laboratory information system of moulds isolated between January 2005 and December 2007. Patient case notes were also reviewed.

RESULTS

A total of 502 isolates (from 273 patients) were found. 20 patients with clinical diagnosis of a probable fungal infection had mixed Aspergillus species.

CONCLUSIONS

In most instances, the isolation of Aspergillus species from non-sterile sites does not represent clinical disease, but only colonisation/contamination. However, for high-risk patients including transplant recipients, a positive culture is associated with invasive disease. Our tertiary centre routinely reports single fungal isolates and mixed cultures with appropriate comments, and those considered significant will also have susceptibility testing carried out. The correlation of culture results with clinical features can differentiate between invasive disease and contamination.

Gradient of microglial activation in the brain of SIV infected macaques

Brains of macaques inoculated with macrophage-tropic, neurovirulent virus 7F, with lymphocyte-tropic SIV mac239, or with dual-tropic SIVmac239/1yE, were examined for microglial activation, astrocyte activation, apoptosis and neuron loss. The brain one animal inoculated with neurovirulent virus 7f showed massive microglial activation as assessed by expression of the major histo-compatibility complex class II (MHC-II). In this animal very numerous, large microglial nodules expressing MHC-II were concentrated in the basal pons and internal capsule. These microglial nodules contained cells undergoing apoptosis detected by in situ end labeling of fragmented DNA. In this animal, neuron loss was apparent near the microglial nodules. In the animals inoculated with SIVmac239 or SIVmac239/17E, pathologic changes such as perivascular cuffing and formation of microglial nodules were absent. However, increased expression of MHC-11 by microglial cells was also concentrated in white matter of the basal pons, midbrain and internal capsule. These results indicate the microglial activation in SIV-infected macaques follows a ventral to dorsal gradient regardless of viral tropism. These results also show that the type and severity of neuropathological changes in SIV-infected macaques is highly dependent on the tropism of the inoculated virus.

Airway cellularity, lipid laden macrophages and microbiology of gastric juice and airways in children with reflux oesophagitis

BACKGROUND

Gastroesophageal reflux disease (GORD) can cause respiratory disease in children from recurrent aspiration of gastric contents. GORD can be defined in several ways and one of the most common method is presence of reflux oesophagitis. In children with GORD and respiratory disease, airway neutrophilia has been described. However, there are no prospective studies that have examined airway cellularity in children with GORD but without respiratory disease. The aims of the study were to compare (1) BAL cellularity and lipid laden macrophage index (LLMI) and, (2) microbiology of BAL and gastric juices of children with GORD (G+) to those without (G-).

METHODS

In 150 children aged < 14-years, gastric aspirates and bronchoscopic airway lavage (BAL) were obtained during elective flexible upper endoscopy. GORD was defined as presence of reflux oesophagitis on distal oesophageal biopsies.

RESULTS

BAL neutrophil% in G- group (n = 63) was marginally but significantly higher than that in the G+ group (n = 77), (median of 7.5 and 5 respectively, p = 0.002). Lipid laden macrophage index (LLMI), BAL percentages of lymphocyte, eosinophil and macrophage were similar between groups. Viral studies were negative in all, bacterial cultures positive in 20.7% of BALs and in 5.3% of gastric aspirates. BAL cultures did not reflect gastric aspirate cultures in all but one child.

CONCLUSION

In children without respiratory disease, GORD defined by presence of reflux oesophagitis, is not associated with BAL cellular profile or LLMI abnormality. Abnormal microbiology of the airways, when present, is not related to reflux oesophagitis and does not reflect that of gastric juices.

Leptin receptor expression in fetal lung increases in late gestation in the baboon: a model for human pregnancy

Leptin produced by both adipose tissue and the placental trophoblast, has been proposed to regulate numerous aspects of human conceptus development. Although recent animal studies have suggested an additional role for the polypeptide in fetal lung maturation, no evidence has been reported in primates. Therefore, we employed the baboon (Papio sp.), a well-characterized primate model for human pregnancy, to determine the presence and ontogeny of leptin receptor in fetal lung with advancing gestation. Lungs were collected from fetal baboons, early in gestation (days 58-62, n = 4), at mid gestation (days 98-102, n = 4), and late in gestation (days 158-165, n = 4) (term 184 days). mRNA transcripts for leptin (LEP) and both long and short intracellular domain isoforms of the leptin receptor (LEP-R(L) and LEP-R(S)) were assessed by RT-PCR. leptin receptor protein was evaluated by immunoblotting and cell types expressing leptin receptor were identified in late pregnancy by immunohistochemistry. Fetal serum leptin concentrations, determined by RIA, remained relatively unchanged at 5.7 +/- 1.1 ng/ml (mean +/- s.e.m.) in mid pregnancy and 8.4 +/- 3.0 ng/ml in late pregnancy (P > 0.05). Although leptin were detectable in fetal lung, no changes in transcript abundance were apparent with advancing gestation. However, transcripts for both LEP-R(L) and LEP-R(S) receptor isoforms increased several-fold (P < 0.05) in fetal lung between mid and late gestation, while leptin receptor protein was detectable only in late pregnancy. leptin receptor was localized in distal pulmonary epithelial cells, including type II pneumocytes. In conclusion, leptin is present in the fetal baboon and its receptor is enhanced during late gestation in cells responsible for the synthesis of pulmonary surfactant. Collectively, these and past findings may suggest a modulatory role for the polypeptide in pulmonary development and/or may identify leptin receptor as a physiological marker of primate fetal lung maturity.

Transient early post-inoculation anti-retroviral treatment facilitates controlled infection with sparing of CD4+ T cells in gut-associated lymphoid tissues in SIVmac239-infected rhesus macaques, but not resistance to rechallenge

Like human immunodeficiency virus infection of humans, infection of rhesus macaques with pathogenic simian immunodeficiency virus (SIV) strains typically results in persistent progressive infection, leading to clinically significant immunosuppression. In previous studies, we administered short term anti-retroviral treatment, shortly after intravenous inoculation with SIVsmE660, in an effort to allow immunologic sensitization under conditions not characterized by overwhelming cytopathic infection compromising the developing immune response. We showed that such treatment allowed control of off treatment viremia and was associated with resistance to rechallenge. Control of off treatment viremia was associated, at least in part, with CD8+ lymphocytes, based on in vivo CD8 depletion studies. In the present study, six rhesus macaques were infected intravenously with 100 MID50 of SIVmac239; four then received 30 days of treatment with tenofovir 9-[2-(R)-(phosphonomethoxy)propyl]adenine (PMPA); 20-30 mg/kg, subcutaneously) starting 24 hours post-inoculation. Tenofovir-treated animals showed low (<500 copy Eq/ml) or undetectable (<100 copy Eq/ml) plasma SIV RNA levels during treatment, with undetectable plasma viremia following discontinuation of treatment. Plasma SIV RNA remained <100 copy Eq/ml, even after depletion of CD8+ lymphocytes, 6 weeks after discontinuation of tenofovir treatment. In contrast to untreated infected control animals that showed substantial depletion of CD4+ T cells from gut-associated lymphoid tissues (GALT), tenofovir-treated animals showed sparing of GALT CD4+ T cells both during the treatment period and in the off treatment follow-up period. However, in contrast to earlier results with animals infected with SIVsmE660, in the present study, the animals did not develop readily measurable cellular anti-SIV immune responses, and did not resist homologous rechallenge with SIVmac239, administered 44 weeks after the initial infection. Differences in the animals and virus strains employed may in part account for the differences in results observed. Comparative analysis of virologic and immunologic parameters in this model system may provide important insights for understanding the basis of effective immunologic control of SIV infection.

The time-course of the response to the FMRFamide-related peptide PF4 in Ascaris suum muscle cells indicates direct gating of a chloride ion-channel

We investigated the effects of PF4 on Ascaris suum somatic muscle cells using a 2 electrode current-clamp technique. PF4 is a FaRP (FMRFamide-related peptide), originally isolated from the free-living nematode Panagrellus redivivus. PF4 caused hyperpolarization and an increase in chloride ion conductance when it was applied to the muscle cells of the Ascaris body wall. The delay between the application of the peptide and the appearance of the response was measured and compared with that of gamma-amino butyric acid (GABA), a compound that directly gates ion channels, and with PF1, a FaRP that acts via an intracellular signal transduction mechanism. The PF4 and GABA delay times were not significantly different; they were 1.51+/-0.11 sec and 1.22+/-0.10 sec respectively. The delay following application of PF1, 3.75+/-0.51 sec, was significantly longer. The rapid response to PF4 is consistent with direct gating of a chloride ion channel, which has not been described elsewhere in the literature.

Expanded polyglutamine peptides alone are intrinsically cytotoxic and cause neurodegeneration in Drosophila

Several dominant, late-onset neurodegenerative diseases (e.g. Huntington's disease) are caused by expansion of polyglutamine (polyQ) repeats within specific proteins. The diverse, yet overlapping, pathology of these diseases could be due to novel deleterious functions unique to each protein or to a common pathophysiology mediated by the long polyQ chains themselves. By engineering Drosophila to express different polyQ peptides, we find that expanded polyQ chains alone are intrinsically cytotoxic and cause neuronal degeneration and early adult death. We further find that this intrinsic toxicity is dependent on cell type and polyQ length and that the inclusion of other amino acids modifies and reduces toxicity. This is the first in vivo evidence that polyQs, when removed from their disease gene context, cause neurotoxicity. These studies provide a basis for understanding the diverse clinical presentations in terms of the intrinsic cytotoxic effect of polyQ peptides being modulated by protein context. Parallel experiments in which cytotoxic polyQ expansions were engineered into Dishevelled, a Drosophila protein containing a naturally occurring polyQ tract, strongly suggest that the effect of a toxic polyQ peptide can be neutralized by protein context. This animal model provides a simple and effective means of screening for therapeutics that relieves the polyQ-induced lethality, independent of any particular disease gene. By quantifying the degree of lethality in several transgenic lines, we have identified a number of genetically modified strains that are suitable for eventual testing of compounds or genes that ameliorate the pathology of polyQ peptides.

Parents with severe mental illness and their children: the need for human services integration

This article presents the findings and recommendations of a statewide interagency task force on parents with mental illness who have young children. Based on testimony from consumers, providers, and advocates, the task force concluded that this is a substantial and neglected public policy issue requiring an intergovernmental, services integration approach. Recommendations were made in the areas of services, policies and procedures, and service coordination.

Management of thyroid carcinoma with radioactive 131I

PURPOSE

To evaluate the role of radioactive 131I in the management of patients with well differentiated carcinoma of the thyroid.

METHODS AND MATERIALS

Between 1965 and 1995, a total of 117 patients with well-differentiated carcinoma of the thyroid underwent either lobectomy or thyroidectomy followed by 100-150 mCi of 131I.

RESULTS

With a median follow-up of 8 years, only four patients (3%) developed a recurrence of their disease. The 5-year actuarial survival was 97% with a 10-year survival of 91%. There were no severe side effects noted after 131I therapy.

CONCLUSIONS

Radioactive 131I is a safe and effective procedure for the majority of patients with well-differentiated thyroid carcinoma. We currently recommend that all patients undergo a subtotal or total thyroidectomy followed by 131I thyroid scanning approximately 4 weeks after surgery. If the thyroid scan shows no residual uptake and all disease is confined to the thyroid, we recommend following patients with annual thyroid scans and serum thyroglobulin levels. If there is any residual uptake detected in the neck or if the tumor extends beyond the thyroid, we recommend routine thyroid ablation of 100-150 mCi of radioactive 131I.

dishevelled is required during wingless signaling to establish both cell polarity and cell identity

The dishevelled gene of Drosophila is required to establish coherent arrays of polarized cells and is also required to establish segments in the embryo. Here, we show that loss of dishevelled function in clones, in double heterozygotes with wingless mutants and in flies bearing a weak dishevelled transgene leads to patterning defects which phenocopy defects observed in wingless mutants alone. Further, polarized cells in all body segments require dishevelled function to establish planar cell polarity, and some wingless alleles and dishevelled; wingless double heterozygotes exhibit bristle polarity defects identical to those seen in dishevelled alone. The requirement for dishevelled in establishing polarity in cell autonomous. The dishevelled gene encodes a novel intracellular protein that shares an amino acid motif with several other proteins that are found associated with cell junctions. Clonal analysis of dishevelled in leg discs provides a unique opportunity to test the hypothesis that the wingless dishevelled interaction species at least one of the circumferential positional values predicted by the polar coordinate model. We propose that dishevelled encodes an intracellular protein required to respond to a wingless signal and that this interaction is essential for establishing both cell polarity and cell identity.

Immunochemical Properties of Fc Fragment of Rabbit γG-Globulin

Various fractions comprising Fc fragment appear to be similar in their reactivity to horse and goat anti-rabbit γG-globulin serum, as determined by immunodiffusion and quantitative immunoprecipitation techniques. These fractions show marked differences in their anti-complementary properties. These results indicate that the anti-complementary site of Fc fragment may be different from its major antigenic determinant.