A Needs Assessment of Family Physicians to Inform Development of Educational Resources on Antipsychotic Use in Dementia

OBJECTIVES

Objectives of this study were to (1) assess the needs and preferred resources of Iowa physicians to inform the development of educational resources for best practice dementia care and (2) compare the responses of nursing home medical directors with nonmedical directors.

METHODS

Of 498 physicians, 101 (20%) completed and returned the survey. Family physicians were obtained from a list of family physicians from the Iowa Board of Medical Examiners. Respondent answers were summarized and presented as total numbers and percentages in tables. Significant differences between medical directors and nonmedical directors were evaluated using chi-square tests, Fisher exact tests, and Wilcoxon rank-sum tests.

RESULTS

Medical directors and nonmedical directors had similar preferences for resources used and information needs. Online resources, pocket guides, a handbook, consulting pharmacists, and facility in-services were the most commonly preferred sources of new information. Medical directors were significantly more aware of the Food and Drug Administration warning on antipsychotic use in dementia and treated more nursing home patients. No differences were observed between groups related to confidence in and use of nondrug strategies instead of antipsychotics to manage behavioral symptoms of dementia.

CONCLUSION

The results of this survey illustrate physician preferences for information and resources on the management of behavioral and psychological symptoms in dementia. Information was used to inform the development of resources to aid physicians and other health care providers in making decisions about managing these symptoms.

Delirium detection by a novel bispectral electroencephalography device in general hospital

AIM

Delirium is common and dangerous among elderly inpatients; yet, it is underdiagnosed and thus undertreated. This study aimed to test the diagnostic characteristics of a noninvasive point-of-care device with two-channel (bispectral) electroencephalography (EEG) for the screening of delirium in the hospital.

METHODS

Patients admitted to the University of Iowa Hospitals and Clinics were assessed for the presence of delirium with a clinical assessment, the Confusion Assessment Method for Intensive Care Unit and Delirium Rating Scale. Subsequently, we obtained a 10-min bispectral EEG (BSEEG) recording from a hand-held electroencephalogram device during hospitalization. We performed power spectral density analysis to differentiate between those patients with and without delirium.

RESULTS

Initially 45 subjects were used as a test dataset to establish a cut-off. The BSEEG index was determined to be a significant indicator of delirium, with sensitivity 80% and specificity 87.7%. An additional independent validation dataset with 24 patients confirmed the validity of the approach, with a sensitivity of 83.3% and specificity of 83.3%.

CONCLUSION

In this pilot study, the BSEEG method was able to distinguish delirious patients from non-delirious patients. Our data showed the feasibility of this technology for mass screening of delirium in the hospital.

Impact of programs to reduce antipsychotic and anticholinergic use in nursing homes

Introduction

Antipsychotics are used for managing behavioral and psychological symptoms of dementia (BPSD) but have risks. Anticholinergics can worsen outcomes in dementia. The Improving Antipsychotic Appropriateness in Dementia Patients educational program (IA-ADAPT) and Centers for Medicare and Medicaid Services Partnership to Improve Dementia Care (CMS Partnership) promote improved care for BPSD. The purpose of this study was to evaluate the impact of these programs on medication use and BPSD among nursing home residents.

Methods

This quasi-experimental longitudinal study used Medicare and assessment data for Iowa nursing home residents from April 2011 to December 2012. Residents were required to be eligible for six continuous months for inclusion. Antipsychotic use and anticholinergic use were evaluated on a monthly basis, and changes in BPSD were tracked using assessment data. Results are presented as odds ratios (ORs) per month after exposure to the IA-ADAPT or the start of the CMS Partnership.

Results

Of 426 eligible Iowa nursing homes, 114 were exposed to the IA-ADAPT in 2012. Nursing home exposure to the IA-ADAPT was associated with reduced antipsychotic use (OR [95% CI] = 0.92 [0.89–0.95]) and anticholinergic use (OR [95% CI] = 0.95 [0.92–0.98]), reduced use of excessive antipsychotic doses per CMS guidance (OR [95% CI] = 0.80 [0.75–0.86]), increased odds of a potentially appropriate indication among antipsychotic users (OR [95% CI] = 1.04 [1.00–1.09]), and decreased documentation of verbal aggression (OR [95% CI] = 0.96 [0.94–0.99]). Facilities with two or more IA-ADAPT exposures had greater reductions in antipsychotic and anticholinergic use than those with only one. The CMS Partnership was associated with reduced antipsychotic use (OR [95% CI] = 0.96 [0.94–0.98]) and decreased documentation of any measured BPSD (OR [95% CI] = 0.98 [0.97–0.99]) as well as delirium specifically (OR [95% CI] = 0.98 [0.96–0.99]).

Discussion

This study suggests that the IA-ADAPT and the CMS Partnership improved medication use with no adverse impact on BPSD.

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IA-ADAPT is a training program with decision aids to improve dementia care.

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The CMS Partnership is a national initiative with similar goals.

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IA-ADAPT training was associated with reduced antipsychotic and anticholinergic use.

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The CMS Partnership was associated with reduced antipsychotic use.

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No adverse effects on behavioral or psychological symptoms were detected.

Validity of the Delirium Observation Screening Scale in Identifying Delirium in Home Hospice Patients

BACKGROUND

Delirium is common in home hospice patients and conveys significant morbidity to both patients and caregivers. The Delirium Observation Screening Scale (DOS) was developed to improve delirium recognition but has yet to be validated in the home hospice setting.

OBJECTIVE

This pilot study aimed to explore the accuracy of the DOS for identifying delirium in home hospice patients.

DESIGN

Prospective delirium evaluation using a convenience sample.

SETTING/PARTICIPANTS

Community hospice patients were approached for study inclusion.

MEASUREMENTS

Participants were assessed using the Delirium Rating Scale-Revised-98 (DRS-R-98), with results being categorized as "delirium" or "no delirium." The Delirium Observation Screening Scale scores, completed by hospice nurses during weekly patient assessment visits, were compared to the DRS-R-98 results.

RESULTS

Within this population, 30/78 (38%) assessments were categorized as delirious. In the majority of assessments, 69/75 (92%), the DRS-R-98 and DOS provided congruent results. There were 5 false positives and 1 false negative, demonstrating the DOS to be a clinically useful tool with a sensitivity of 0.97 and specificity of 0.89.

CONCLUSION

The DOS appears to be an accurate way to screen for delirium in home hospice patients. Validation of the DOS may help to improve delirium recognition and treatment and has the potential to increase quality of life in this vulnerable population. This input will also be taken into consideration in the development of a systematic screening procedure for delirium diagnosis at our local hospice, which we hope will be generalizable to other hospice agencies.

A qualitative exploration of perceived key knowledge and skills in end-of-life care in dementia patients among medical, nursing, and pharmacy students

BACKGROUND

The steady increase in the number of people living and dying with dementia, coupled with the recent focus on quality of care, has highlighted the importance of dementia training for health care professionals. This exploratory study aimed to discover which skills health care students felt were important in providing quality end-of-life care to dementia patients.

METHODS

Ninety-four medicine, nursing, and pharmacy students participated in a larger study using open-ended and closed questions to explore attitudes related to caring for dementia patients at the end of life. This study looks at the student responses to an open-ended question regarding the skills and knowledge they believe are needed to provide end-of-life care to dementia patients. Individual responses were reviewed by the researchers, coded into key issues, and tabulated for frequency of occurrences and group differences.

RESULTS

Several common issues emerged: knowledge, patience, empathy, understanding, family involvement, compassion, medication knowledge, respect/patient autonomy, communication, quality of life, and patient education. Significant differences were observed among the participant groups on the following issues: Patience and understanding (pharmacy students mentioned these issues less frequently than medical and nursing students), compassion (medical students mentioned this issue more frequently than pharmacy students), and medication knowledge (pharmacy students mentioned this issue more frequently than medical and nursing students).

CONCLUSIONS

Different health care disciplines (in-training) value different skill sets for the provision of dementia care at the end-of-life. As health care education for dementia patients at the end of life is expanded, it will be important to understand which skills both patients and health care students value.

Medical manuscripts impact of hospice enrollment on cost and length of stay of a terminal admission

OBJECTIVE

To determine whether hospice enrollment at the time of a terminal admission alters the length of stay (LOS) or costs compared with patients not enrolled in hospice.

METHODS

Retrospective chart review of all nontraumatic inpatient deaths of patients with a previous admission in the preceding 12 months at an academic hospital.

RESULTS

209 patients had a nontraumatic death and an admission in the year prior to the terminal admission. Patients enrolled in hospice had a shorter LOS (P = .02) and lower cost (P < .0001) than patients not enrolled at the time of their terminal admission.

CONCLUSIONS

Enrollment in hospice during a terminal admission decreased cost and LOS. Hospice may be a way to provide more cost-effective, appropriate care to dying patients.

Risk factors for delirium in patients undergoing hematopoietic stem cell transplantation

BACKGROUND

Delirium is common after hematopoietic stem cell transplantation (HSCT) and is associated with increased morbidity and mortality. Early recognition and treatment have been shown to improve long-term outcomes. We sought to investigate the relationship between potential risk factors and the development of delirium following HSCT.

METHODS

Fifty-four inpatients admitted for HSCT were assessed prospectively for delirium every 2 to 3 days during their inpatient stay using standardized delirium and neuropsychological measures. Self reports of medical history, medical records, and neurocognitive and psychiatric assessments were used to identify risk factors. Both pre- and post-HSCT risk factors were examined.

RESULTS

Delirium incidence was 35% and occurred with highest frequency in the 2 weeks following transplant. The only pre-transplantation risk factor was lower oxygen saturation (P = .003). Post-transplantation risk factors for delirium included higher creatinine (P < .0001), higher blood urea nitrogen levels (P = .005), lower creatinine clearance (P = .0006), lower oxygen saturation (P = .001), lower hemoglobin (P = .04), and lower albumin (P = .03). There was no observed association with level of cognitive performance, transplant type, disease severity, medical comorbidity index, age, or conditioning regimen.

CONCLUSIONS

Routine laboratory values can assist in the identification of high-risk patients before delirium onset to improve early detection and treatment of delirium after HSCT.

Hospice eligibility in patients who died in a tertiary care center

BACKGROUND

Hospice is a service that patients, families, and physicians find beneficial, yet a majority of patients die without receiving hospice care. Little is known about how many hospitalized patients are hospice eligible at the time of hospitalization.

METHODS

Retrospective chart review was used to examine all adult deaths (n = 688) at a tertiary care center during 2009. Charts were selected for full review if the death was nontraumatic and the patient had a hospital admission within 12 months of the terminal admission. The charts were examined for hospice eligibility based on medical criteria, evidence of a hospice discussion, and hospice enrollment.

RESULTS

Two hundred nine patients had an admission in the year preceding the terminal admission and a nontraumatic death. Sixty percent were hospice eligible during the penultimate admission. Hospice discussions were documented in 14% of the hospice-eligible patients. Patients who were hospice eligible had more subspecialty consults on the penultimate admission compared to those not hospice eligible (P = 0.016), as well as more overall hospitalizations in the 12 months preceding their terminal admission (P = 0.0003), and fewer days between their penultimate admission and death (P = 0.001).

CONCLUSION

The majority of terminally ill inpatients did not have a documented discussion of hospice with their care provider. Educating physicians to recognize the stepwise decline of most illnesses and hospice admission criteria will facilitate a more informed decision-making process for patients and their families. A consistent commitment to offer hospice earlier than the terminal admission would increase access to community or home-based care, potentially increasing quality of life.

Proton Magnetic Resonance Spectroscopy in adult cancer patients with delirium

Delirium is associated with a host of negative outcomes, including increased risk of mortality, longer hospital stay, and poor long-term cognitive function. The pathophysiology of delirium is not well understood. Cancer patients undergoing a bone marrow transplant (BMT) are at high risk for developing delirium and Proton Magnetic Resonance Spectroscopy ((1)H MRS) could lead to better understanding of the delirium process. Fourteen BMT patients and 10 controls completed (1)H MRS, positioned above the corpus callosum, shortly after delirium onset or at study end if no delirium occurred. In the BMT-delirium group, statistically significantly elevated tCho/tCr was found in contrast to the BMT-no delirium group. The BMT-delirium group also showed statistically significantly lesser NAA/tCho compared with both controls and the BMT-no delirium group. Elevated choline and reduced NAA indicate inflammatory processes and white matter damage as well as neuronal metabolic impairment. Further research is needed to separate the choline peaks, as well as more detailed collection of medication regimens to determine whether a higher choline concentration is a function of the delirium process or cancer treatment effects.

The neuropsychological course of acute delirium in adult hematopoietic stem cell transplantation patients

Although delirium is a common medical comorbidity with altered cognition as its defining feature, few publications have addressed the neuropsychological prodrome, profile, and recovery of patients tested during delirium. We characterize neuropsychological performance in 54 hemapoietic stem cell/bone marrow transplantation (BMT) patients shortly before, during, and after delirium and in BMT patients without delirium and 10 healthy adults. Patients were assessed prospectively before and after transplantation using a brief battery. BMT patients with delirium performed more poorly than comparisons and those without delirium on cross-sectional and trend analyses. Deficits were in expected areas of attention and memory, but also in psychomotor speed and learning. The patients with delirium did not return to normative "average" on any test during observation. Most tests showed a mild decline in the visit before delirium, a sharp decline with delirium onset, and variable performance in the following days. This study adds to the few investigations of neuropsychological performance surrounding delirium and provides targets for monitoring and early detection; Trails A and B, RBANS Coding, and List Recall may be useful for delirium assessment.

The role of the family physician in the referral and management of hospice patients

Hospice is available for any patient who is terminally ill and chooses a palliative care approach. Because of the close relationship that primary care physicians often have with their patients, they are in a unique position to provide end-of-life care, which includes recognizing the need for and recommending hospice care when appropriate. The hospice benefit covers all expenses related to the terminal illness, including medication, nursing care, and equipment. Hospice should be considered when a patient has New York Heart Association class IV heart failure, severe dementia, activity-limiting lung disease, or metastatic cancer. Timely referrals are beneficial to both patient and hospice because of the cost related to initiating services and the time required to form a therapeutic relationship. Once the decision to refer to hospice is made, the family physician typically continues to be the patient's primary attending physician. The attending physician is expected to remain in charge of the patient's care, write orders, see the patient for office visits, and complete and sign the death certificate. Hospice, in turn, is a valuable physician resource when it comes to medication dosages, symptom management, and communication with patients and their families.

Regulation of parathyroid hormone-related protein expression in a canine squamous carcinoma cell line by colchicine

The regulation of parathyroid hormone-related protein expression by colchicine, vinblastine, nocodazole, taxol, transforming growth factor-beta1 (TGFbeta1), and epidermal growth factor (EGF) was investigated in a canine squamous carcinoma cell line (SCC 2/88 cells). SCC 2/88 cells were stably transfected with a human P2/P3 PTHrP promoter-luciferase reporter gene construct and gene expression was measured after chemical treatments. The greatest increase in reporter gene expression was observed after colchicine treatment and small increases occurred after treatment with vinblastine, taxol, TGFbeta1, or EGF. Nocodazole had no significant effect on reporter gene expression. Colchicine also increased PTHrP steady state mRNA expression and PTHrP secretion by SCC 2/88 cells. These results demonstrated that PTHrP production was increased in SCC 2/88 cells by colchicine and suggested that factors or events during mitosis are capable of stimulating PTHrP production. An increase in PTHrP production during mitosis of malignant epithelial cells may be important in the pathogenesis of humoral hypercalcemia of malignancy.

Dependence of humoral hypercalcemia of malignancy on parathyroid hormone-related protein expression in the canine anal sac apocrine gland adenocarcinoma (CAC-8) nude mouse model

Circulating parathyroid hormone-related protein (PTHrP) is the primary humoral factor in dogs with spontaneous humoral hypercalcemia of malignancy (HHM) and adenocarcinomas derived from apocrine glands of the anal sac. A canine apocrine adenocarcinoma model of HHM in nude mice (CAC-8) was developed and characterized. After 32 passages in vivo, a spontaneous variant of the tumor (CAC-8 Lo Ca) that has altered cellular morphology and that fails to induce HHM in tumor-bearing nude mice has been discovered. The hypercalcemic and nonhypercalcemic tumor lines were compared by tumor weight, effect on body weight, serum calcium concentration, plasma PTHrP concentration, histopathology, expression of PTHrP protein by radioimmunoassay and immunohistochemistry, and expression of PTHrP mRNA by in situ hybridization and northern blot analysis. Messenger RNA expression for other factors and cytokines known to alter PTHrP secretion or bone resorption in vivo, including tumor necrosis factor alpha (TNF alpha), interleukin (IL)-1, IL-6, and transforming growth factor beta (TGF beta), were also measured in the adenocarcinomas. There was no significant difference in weight of individual tumors. Nude mice bearing the CAC-8 (Lo Ca) tumor maintained normal body weight as compared with non-tumor-bearing control mice. In contrast, mice with the CAC-8 (Hi Ca) tumor had markedly decreased body weights. The CAC-8 (Hi Ca) tumor-bearing mice had severe hypercalcemia (mean = 13.4 mg/dl) and increased plasma concentrations of PTHrP (30.4 pM), whereas the CAC-8 (Lo Ca) tumor-bearing mice had a mean serum calcium concentration of 10.1 mg/dl and mildly increased PTHrP concentrations (5.7 pM) as compared with control mice (9.0 mg/dl and 1.0 pM, respectively). The original tumor (CAC-8 [Hi Ca]) is a well-differentiated adenocarcinoma, whereas the variant tumor (CAC-8 [Lo Ca]) is a solid carcinoma with both polygonal and spindle-shaped cells. The CAC-8 (Lo Ca) tumor had decreased PTHrP mRNA expression and protein synthesis. Messenger RNA expression of TGF beta, TNF alpha, IL-1, and IL-6 was similar in both tumors and was consistent with the central role of PTHrP in the induction of hypercalcemia in this animal model.

Effect of transforming growth factor-beta1 on parathyroid hormone-related protein secretion and mRNA expression by normal human keratinocytes in vitro

Parathyroid hormone-related protein (PTHrP) is produced by a wide range of neoplastic and normal cells, including keratinocytes where it may regulate growth and differentiation. Transforming growth factor-beta (TGF-beta) is a growth factor produced by many cells, including keratinocytes where it regulates epidermal homeostasis. TGF-beta has been reported to be cosecreted with PTHrP in some neoplasms and to stimulate PTHrP production by neoplastic keratinocytes. However, the effects of TGF-beta on PTHrP production by normal keratinocytes are not well characterized. In this study, we investigated the effects of endogenous and exogenous TGF-beta on PTHrP production by normal human foreskin keratinocytes. PTHrP secretion, mRNA expression, and mRNA transcription in vitro were determined by N-terminal radioimmunoassay, ribonuclease protection assay, and transient transfections. PTHrP production and secretion of latent TGF-beta activity were greatest in proliferating keratinocytes prior to and at confluence of monolayer cultures. TGF-beta1 increased PTHrP mRNA expression by normal keratinocytes in a dose-dependent manner with maximal stimulation at 6-1 2 h after treatment. In addition, keratinocytes treated with a monoclonal anti-TGF-beta antibody expressed decreased levels of PTHrP mRNA. The increased levels of PTHrP mRNA following TGF-beta1 treatment were owing, at least partly, to an increase in PTHrP mRNA stability. TGF-beta1 failed to activate transcription of the luciferase reporter gene driven by either the human or mouse PTHrP promoters. In conclusion, TGF-beta1 functions as a paracrine or autocrine regulator of PTHrP production in normal human keratinocytes, and this may play a role in the regulation of keratinocyte proliferation or differentiation.

Influence of extracellular matrix macromolecules on normal human keratinocyte phenotype and parathyroid hormone-related protein secretion and expression in vitro

Parathyroid hormone-related protein (PTHrP) is produced by a wide range of neoplastic and normal cells, including keratinocytes where it may be involved in the regulation of cellular growth and differentiation. There is evidence that the nature of the extracellular matrix (ECM) influences gene expression and cell phenotype. The objective of this study was to investigate the phenotype of normal human keratinocytes grown on different types of ECM (basement membrane components or collagen type I), as well as the expression and secretion of PTHrP. Normal keratinocytes grown on basement membrane extract (Matrigel) actively reorganized the matrix and formed networks of cells with traction of the matrix. This was associated with linear arrays of intracellular microtubules and formation of prominent actin stress fibers and was suppressed by treatment with colchicine or cytochalasin B, confirming the role of the cytoskeleton in this process. In addition, growth on Matrigel was associated with increased PTHrP nuclear translocation, secretion, and mRNA expression compared to growth on collagen where keratinocytes exhibited decreased proliferation and increased differentiation. PTHrP, as a paracrine keratinocyte factor, did not appear to mediate the morphologic changes, since they were not altered by treatment with neutralizing anti-PTHrP antibodies. It was concluded that different types of ECM influenced the morphologic, functional, and proliferative characteristics of keratinocytes, as well as the level of PTHrP expression and secretion in vitro.

Regulation of parathyroid hormone-related protein secretion and mRNA expression in normal human keratinocytes and a squamous carcinoma cell line

Parathyroid hormone-related protein (PTHrP) has been identified as a causative factor in the pathogenesis of humoral hypercalcemia of malignancy (HHM). The regulation and mechanisms of PTHrP secretion in most normal and malignant cells are unknown. PTHrP secretion, mRNA expression, and transcription were measured in neoplastic human squamous carcinoma cells (A253) and normal human foreskin keratinocytes (NHFK) by radioimmunoassay, RNase protection assay, and transient transfections of the 5'-flanking region of human PTHrP in a luciferase expression vector. Mechanisms of PTHrP secretion were investigated using chemicals (monensin, colchicine, cytochalasin B, guanosine 5'-[gamma-thio]triphosphate (GTPgammaS)) that interfere with or facilitate intracellular transport. Monensin inhibited PTHrP secretion in both NHFK and A253 cells. Ultrastructurally, monensin caused dilatation of rough endoplasmic reticulum and the formation of numerous cytoplasmic secretory vacuoles in both cell lines. Colchicine decreased PTHrP production in NHFK cells and stimulated PTHrP production and mRNA levels in A253 cells. Colchicine also stimulated transcription of the PTHrP-luciferase reporter gene. Cytochalasin B stimulated PTHrP secretion and mRNA expression in A253 cells, but had no effect in NHFK cells. GTPgammaS had no effect on PTHrP secretion in either cell line. It was concluded that PTHrP secretion is dependent on the constitutive movement of secretory vesicles to the cytoplasmic membrane and regulation of PTHrP secretion and mRNA expression are altered in squamous carcinoma cells compared to normal human keratinocytes in vitro.

Altered parathyroid hormone-related protein secretion and mRNA expression in squamous carcinoma cells in vitro

Parathyroid hormone-related protein (PTHrP), a major factor in the pathogenesis of humoral hypercalcemia of malignancy, is produced by many squamous carcinoma cells (SCCs). Two SCC lines were grown in multilayered culture systems and compared to cells grown as monolayers to evaluate the effects of cell proliferation, confluence and differentiation on PTHrP secretion and mRNA expression. Well-differentiated (SCC 2/88) and poorly differentiated (SCC-A253) SCCs were grown as monolayer and three-dimensional cultures on collagen-coated membranes to compare the regulation of PTHrP expression and secretion by the cell lines in vitro. Parathyroid hormone-related protein secretion was evaluated by radioimmunoassay and immunohistochemistry. Messenger RNA expression was analyzed by RNase protection assay and in situ hybridization. Secretion of PTHrP was greatest in preconfluent SCC 2/88 cells in monolayer culture and decreased after confluence, which was the result of decreased PTHrP mRNA expression. In contrast, PTHrP secretion in cultures of SCC-A253 cells reached maximal levels after confluence. In multilayered cultures, total PTHrP secretion and mRNA expression remained high in both SCC 2/88 and SCC-A253 cells, and secretion by the multi-layered cultures was principally in the basal direction. Parathyroid hormone-related protein was present in all cell layers in three-dimensional cultures as determined by immunohistochemistry. These results indicated that multilayered cultures of SCCs produced PTHrP continuously, whereas decreased proliferation in monolayer cultures was associated with decreased PTHrP production. Multilayered cultures represent a better system to investigate PTHrP secretion and mRNA expression in vitro and PTHrP secretion by SCCs in vivo may be greatest by proliferating cells.

In vitro model of parathyroid hormone-related protein secretion from mammary cells isolated from lactating cows

Parathyroid hormone-related protein (PTHrP) is produced by the lactating mammary gland and is present in milk in a biologically active form. The goal of this investigation was to determine if cells cultured from the lactating mammary glands of cows would secrete PTHrP in vitro. Mammary acini were isolated from lactating cows at 1-6 wk after calving, and fresh or cryopreserved mammary acini were cultured for 14 d on Type I collagen. Cultures on thick layers of collagen (2.5 mm) were detached and allowed to contract on Day 6. PTHrP production was measured by N-terminal radioimmunoassay and bioassay (increased cAMP levels in ROS 17/2.8 osteoblast-like cells). The mammary cells reached confluence at Day 6. PTHrP production was low at Day 2 (< 0.5 ng/ml) but increased to peak production (2-4 ng/ml) at approximately Day 6 and remained constant until Day 14. Immunoreactive and bioactive PTHrP levels in the culture medium correlated well. The cultures produced lactoferrin (2,000-2,300 ng/ml and alpha s1-casein (14-19 ng/ml). Prolactin stimulated PTHrP production approximately 50% on Days 6-14. PTHrP production was increased approximately 100% by treatment with epidermal growth factor (10 ng/ml) for 2 d. Morphologic evaluation of cultures on thick, contracted collagen at Day 14 revealed an inner layer of mammary epithelial cells overlying myoepithelial cells and an outer layer of collagen containing stromal cells. Immunohistochemistry demonstrated positive staining for PTHrP and cytokeratin in both mammary epithelial and myoepithelial cells and alpha-smooth muscle actin in myoepithelial cells. These data demonstrated that cryopreserved mammary tissue from lactating cows could be cultured in vitro and secreted PTHrP in a regulated manner. This in vitro model will be useful to investigate the function and regulation of PTHrP in the lactating mammary gland.

Canine glyceraldehyde-3-phosphate dehydrogenase complementary DNA: polymerase chain reaction amplification, cloning, partial sequence analysis, and use as loading control in ribonuclease protection assays

OBJECTIVE

To use canine glyceraldehyde-3-phosphate dehydrogenase complementary DNA (GAPDH cDNA) as a template in ribonuclease (RNase) protection assays to measure canine GAPDH mRNA expression.

DESIGN AND PROCEDURE

Primers designed from the human GAPDH gene were used to amplify a 191-base pair canine GAPDH cDNA by reverse-transcription polymerase chain reaction. The cDNA was sequenced, and used as a template for RNase protection assay.

SAMPLE POPULATION

Total RNA was isolated from a canine squamous carcinoma cell line.

RESULTS

Canine GAPDH cDNA had a high degree of homology to human, rat, and mouse GAPDH. In vitro transcription of canine GAPDH cDNA was used to produce complementary RNA that detected canine GAPDH mRNA by RNase protection assay.

CONCLUSION

Canine GAPDH cDNA is a useful loading control to be used in RNase protection assays measuring mRNA expression in canine cells or tissues.

Studies on chicken polyclonal anti-peptide antibodies specific for parathyroid hormone-related protein (1-36)

Chicken polyclonal antibodies were prepared against a synthetic peptide corresponding to the first 36 N-terminal amino acids of parathyroid hormone-related protein (PTHrP) by immunizing laying hens. Significant increases of antibodies to PTHrP were first detected after the second immunization. Production of anti-PTHrP egg yolk antibodies peaked 1-2 weeks after the second through sixth immunizations and declined over a period of 2-4 weeks. Polyclonal IgG (IgY) to PTHrP was purified from the egg yolks with high levels of PTHrP specific binding. The anti-PTHrP IgG was used to develop a radioimmunoassay for PTHrP that was able to detect 100 pg PTHrP ml-1 (23 pM) in conditioned cell culture medium. The anti-PTHrP IgG was bound to a solid phase and utilized to immunopurify iodinated [Tyr36]-PTHrP (1-36). Anti-PTHrP IgG inhibited the in vitro biologic activity of PTHrP as demonstrated by the inhibition of adenylate cyclase stimulation in a rat osteoblast-like cell line (ROS 17/2.8). The anti PTHrP IgG was immunopurified and utilized for immunohistochemical localization of PTHrP in canine skin. Chickens were advantageous in producing large amounts of high affinity, neutralizing antibodies to a highly conserved mammalian protein such as PTHrP. The antibodies will be useful to investigate the function and metabolism of PTHrP in vivo and in vitro.