Performance and Stability of New Class of Fetal Bovine Sera (FBS) and Its Lyophilized Form in ELISpot and FluoroSpot Assays: Applications for Monitoring the Immune Response in Vaccine, and Cell and Gene Immunotherapy in Clinical Trials

Interferon-gamma (IFNγ) ELISpot and FluoroSpot are widely used assays to detect functional cell responses in immunotherapy clinical studies. Recognized for their importance in vaccine development studies to quantitate immune responses, these assays have more recently risen to the forefront in cell and gene therapy as well as cancer immunotherapy fields where responses against cancer neoantigens are not easily detectable above assay background. Here, we test a new class of fetal bovine serum (FBS), CultraPure FBS, in ex vivo ELISpot and FluoroSpot assays and cultured FluoroSpot assays following in vitro expansion. Several CultraPure FBS lots that have been specially formulated through the process of lyophilization (lyo-FBS) were compared to liquid CultraPure FBS. We stimulated human PBMCs with antigen-specific peptide pools diluted in media supplemented with liquid CultraPure FBS or lyo-FBS and found equivalent cytokine production with negligible to no assay background with both liquid and lyo-FBS formats. Moreover, the lyo-FBS showed lot-to-lot consistency and 90-day refrigerated (4 °C) stability in both ex vivo direct and in vitro cultured assays. In addition, we present here a method using lyo-FBS for the expansion of low-frequency antigen-specific T cells, mimicking the low frequency seen with cancer neoantigens by utilizing a cultured FluoroSpot assay. Our results demonstrate the presence of Granzyme B, interferon-gamma (IFNγ), and tumor necrosis factor (TNF) production by antigen-specific polyfunctional T cells following a 9-day culture using media supplemented with lyo-FBS.

The visualisation of fingermarks on Pangolin scales using gelatine lifters

Recent media reports document the plight of the Pangolin and its current position as "the most trafficked mammal in the world". They are described by some as scaly anteaters as all species are covered in hard keratinous tissue in the form of overlapping scales acting as a "flexible dermal armour". It is estimated that between 2011 and 2013, 117,000-234,000 pangolins were slaughtered, but the seizures may only represent as little as 10% of the true volume of pangolins being illegally traded. In this paper, methods to visualise fingermarks on Pangolin scales using gelatine lifters is presented. The gelatine lifters provide an easy to use, inexpensive but effective method to help wildlife crime rangers across Africa and Asia to disrupt the trafficking. The gelatine lifting process visualised marks producing clear ridge detail on 52% of the Pangolin scales examined, with a further 30% showing the impression of a finger with limited ridge detail. The paper builds on an initial sociotechnical approach to establishing requirement, then it focuses on the methods and outcomes relating to lifting fingermarks off Pangolin scales using gelatine lifters, providing an evaluation of its use in practice.

Is Preputioplasty Effective and Acceptable?

Foreskin complaints in childhood, if not manageable conservatively, are usually treated by circumcision. A less radical surgical option, when balanitis xerotica obliterans is absent, is preputioplasty. We sent questionnaires to the parents of 23 boys who had had this procedure and 22 replied.

Mean interval since operation was 20 months (range 3-36). The main indications for surgery had been irretractable foreskin in 9, recurrent balanoposthitis in 10 and ballooning on voiding in 3 and the operation had dealt successfully with these in 7, 7, and 3, respectively. In all but one case the parents were satisfied with the cosmetic result. However, in 8 cases (36%) the parents said they would have preferred circumcision and 3 of the boys had been listed for further surgery.

Preputioplasty is a satisfactory alternative to circumcision in selected cases.

No resistance to tenofovir disoproxil fumarate detected after up to 144 weeks of therapy in patients monoinfected with chronic hepatitis B virus

Tenofovir disoproxil fumarate (TDF) is a nucleotide analogue with potent activity against human immunodeficiency virus type 1 and hepatitis B virus (HBV). To date, no reports of HBV clinical resistance to TDF have been confirmed. In two phase 3 studies (GS-US-174-0102 and GS-US-174-0103), 375 hepatitis B e antigen-negative (HBeAg(-) ) patients and 266 HBeAg(+) patients with chronic hepatitis B (some nucleoside-naive and some lamivudine-experienced) were randomized 2:1 to receive TDF (n = 426) or adefovir dipivoxil (ADV; n = 215) for 48 weeks. After week 48, eligible patients received open-label TDF with no interruption. The studies are being continued through week 384/year 8; week 144 data are presented here. Per protocol, viremic patients (HBV DNA level ≥ 400 copies/mL or 69 IU/mL) had the option of adding emtricitabine (FTC) at or after week 72. Resistance analyses of HBV polymerase/reverse transcriptase (pol/RT) were based on population dideoxy sequencing. Phenotypic analyses were conducted in HepG2 cells with recombinant HBV derived from patient serum. Most patients maintained TDF monotherapy treatment across both studies (607/641, 95%). A resistance analysis of HBV pol/RT was performed at the baseline for all patients, for viremic patients at week 144 or at the last time when they were on TDF monotherapy (34 on TDF and 19 on ADV-TDF), and for patients who remained viremic after the addition of FTC (7/20 on TDF and 5/14 on ADV-TDF). No patient developed amino acid substitutions associated with resistance to TDF. Virological breakthrough on TDF monotherapy was infrequent over 144 weeks (13/426, 3%) and was attributed to documented nonadherence in most cases (11/13, 85%). Persistent viremia (≥400 copies/mL) through week 144 was rare (5/641, 0.8%) and was not associated with virological resistance to TDF by population or clonal analyses.

CONCLUSION

No nucleoside-naive or nucleoside-experienced patient developed HBV pol/RT mutations associated with TDF resistance after up to 144 weeks of exposure to TDF monotherapy.

Targeted chemoradiation for metastatic colorectal cancer: A phase I trial of oral capecitabine combined with 131I- huA33

4078

Background: HuA33 is a humanized antibody that targets the A33 antigen, which is highly expressed in intestinal epithelium and >95% of human colon cancers, but not other normal tissues. Previous studies have shown huA33 can target and be retained in a metastatic tumor for 6 weeks, but eliminated from normal colonocytes within days. This phase 1 study used radio-labeled huA33 in combination with capecitabine chemotherapy to target chemoradiation to metastatic colorectal cancer. Methods: The primary objective was safety and tolerability of the combination of capecitabine and 131I-huA33. Pharmacokinetics, biodistribution, immunogenicity, and tumor response were also assessed. Eligibility included measurable metastatic colorectal cancer, adequate hematological and biochemical function, and informed consent. An outpatient scout 131I-huA33 dose was followed by a single therapy infusion one week later, when capecitabine was commenced. Dose escalation occurred over 5 dose levels. Patients were evaluated weekly, with tumor response assessment at the end of the12 week trial. Tumor targeting was assessed using gamma camera and single photon emission computerized tomography (SPECT) imaging. Results: 16 patients have enrolled with 2 currently on treatment, including one in the final dose cohort. Accrual will be completed by March 2007. The dose escalation protocol was amended following 2 dose limiting toxicities in the second cohort, but subsequent cohorts demonstrated good tolerability. Biodistribution analysis demonstrated excellent tumor targeting of the known tumor sites, expected transient bowel uptake, but no other normal tissue uptake. Maximal duration of stable disease is currently 3 years. Conclusions: 131I-huA33 achieves specific targeting of radiotherapy to sites of metastasis and can be safely combined with chemotherapy. This provides an opportunity to deliver chemoradiation specifically to metastatic disease in colorectal cancer patients.

[Table: see text]

No significant financial relationships to disclose.

A phase I single dose escalation trial of ch806 in patients with advanced tumors expressing the 806 antigen

13028

Background: Ch806 is a chimeric antibody (mAb) that binds to a unique epitope only exposed on a transitional untethered form of the Epidermal Growth Factor Receptor (EGFR), and the de2–7 EGFR, but not exposed on wtEGFR. Immunohistochemistry (IHC) studies have demonstrated that the 806 antigen is not detected in any normal human tissue, but is highly expressed in a broad range of epithelial cancers, and in gliomas. Preclinial studies have shown that ch806 has potent anti-tumor activity in xenograft models expressing amplified EGFR or de2–7 EGFR, and is internalized into tumor cells. Methods: The primary objective of this first in man study was to determine the toxicity of increasing single doses of c806. The secondary objectives were to characterize the biodistribution, pharmacokinetics (pK) and tumor uptake of In-111 ch806, to determine human antibody responses (HACA), and to document tumour responses to ch806. Patients with advanced or metastatic disease whose tumors expressed the 806 antigen by IHC received a single infusion of 111In-labelled ch806. 111In-ch806 was administered as a single, 1 hour infusion at dose levels of of 5 mg/m2, 10 mg/m2, 20 mg/m2 and 40 mg/m2. Results: 7 patients (1 at 5mg/m2 dose and 2 each at 10, 20 and 40 mg/m2 doses) have been entered into the study: squamous cell lung (2), colorectal (1), squamous cell anus (1), mesothelioma (1), squamous cell larynx (1) and squamous cell skin with lung metastasis (1). Patients had a median age 66 (range 49–75) and median of 1.5 (range 0–4) prior oncological treatment regimens. No significant toxicities were observed. The biodistribution of ch806 showed excellent targeting of tumour sites in all patients. There was no evidence of any normal tissue uptake of ch806. PK analysis showed comparable Cl at all dose levels (mean ± SD: 34.6 ± 5.0 mL/hr), no normal tissue saturable compartment, and dose dependent Cmax and AUC. HACA analysis is ongoing. One patient had a reduction in size of cervical lymphadenopathy on study, and progressive pulmonary disease at study completion. There was 1 patient with SD and 6 with PD at study completion. Conclusion: ch806 was very well tolerated and targeted a wide range of tumour types with no normal tissue uptake, which is markedly different to other mAbs that target wtEGFR.

No significant financial relationships to disclose.

Is preputioplasty effective and acceptable?

Foreskin complaints in childhood, if not manageable conservatively, are usually treated by circumcision. A less radical surgical option, when balanitis xerotica obliterans is absent, is preputioplasty. We sent questionnaires to the parents of 23 boys who had had this procedure and 22 replied. Mean interval since operation was 20 months (range 3-36). The main indications for surgery had been irretractable foreskin in 9, recurrent balanoposthitis in 10 and ballooning on voiding in 3 and the operation had dealt successfully with these in 7, 7, and 3, respectively. In all but one case the parents were satisfied with the cosmetic result. However, in 8 cases (36%) the parents said they would have preferred circumcision and 3 of the boys had been listed for further surgery. Preputioplasty is a satisfactory alternative to circumcision in selected cases.

Developmental practicum experiences of preservice teachers in deaf education: implications for practicum placement and faculty-student collaborative research

The study examined the developmental practicum experiences of second-year graduate students in deaf education. Participants in the study consisted of a convenient sample of five practicum students. Triangulated data for the study came from the researcher's observational notes, e-mail correspondence with participants, and participants' journals. Inductive analysis was used to analyze the data. Results of the study evinced developmental experiences that are different from those reported in previous studies. The results of the study have significant implications for (a) practicum placement of graduate students in deaf education in terms of site-based orientation, use of the clinical model of supervision, opportunities for self-reflection, and periodic practicum seminars; and (b) faculty-student collaborative research in terms of planning, ethical issues, students' time needs, and training.

Meeting the educational needs of general practitioners for epilepsy

Epilepsy care in general practice has been criticized, but what do GPs feel they deal with most and complete satisfactorily? If criticism is justified, education should be useful in improving epilepsy care, but what do general practitioners want to learn and how do they want to learn it? Questionnaires about these issues were sent to randomly chosen general practitioners throughout the United Kingdom. One hundred and twenty-four out of 200 (62%) responded. They were not biased by age, sex, type of practice or previous interest in epilepsy. Drug treatment and regular review were the two areas of care GPs said they dealt with most, but only half felt they dealt with them well. Sixty-six percent wanted to learn more about drug treatment, 46% about lifestyle advice, 45% about non-drug treatment, 44% about diagnosis and only 16% did not want to learn more about any aspect of care. Weekdays and evenings were the preferred times for study. Courses up to one full day away from practices were popular, distance learning and personal education plans were not, except for a group of younger GPs. When attending courses multi-disciplinary lectures rated highly and nearly three-quarters preferred to attend courses where epilepsy was covered in conjunction with other conditions. Future epilepsy education for GPs should recognize these findings if attendance and positive outcomes are to be maximized.

Interobserver variability in the measurement of internal carotid stenosis

OBJECTIVE

To assess interobserver variability in the measurement of carotid stenoses from digital subtraction angiograms displayed in different ways (nonmagnified or magnified, white or black arteries); and to compare human readers with computer-generated densitometric measurements of vessel stenosis.

METHODS

Digital subtraction angiograms of 20 proximal internal carotid artery stenoses were laser printed in the following ways: (1) Nonmagnified white artery on a black background; (2) Magnified white artery on a black background; (3) Nonmagnified black artery on a white background; (4) Magnified black artery on a white background. This resulted in 80 images of internal carotid artery stenoses. These stenoses were independently measured by 4 radiologists using the North American Symptomatic Carotid Endarterectomy Trial method. A computer-generated densitometric measurement of the black nonmagnified images was also obtained.

RESULTS

The most reliable stenosis measurements were obtained from the nonmagnified black and white artery images. The interobserver variability in the measurement of internal carotid stenoses using these images was quite small. Variability increased with the use of magnification. The computer-generated stenosis measurements were consistently much higher than those of the radiologists.

CONCLUSION

There was significant variability in measurements made from magnified images and between human readers and computer-generated measurements. This has great clinical significance. Readers of digital angiographic images must determine the most reliable, reproducible images generated by their equipment, as these measurements significantly affect treatment of patients with symptomatic internal carotid artery stenosis.

Patient views on primary care services for epilepsy and areas where additional professional knowledge would be welcome

In the past decade there has been increasing interest in the part that general practice can play in the care of people with epilepsy. Primary care services for epilepsy vary from practice to practice. Some studies have suggested that people with epilepsy prefer secondary care services and are not keen for their epilepsy to be managed in general practice, but much of the data were collected in secondary care. This study collected data from various sources about present provision of services, patient satisfaction with services, views about service development, areas where GP knowledge may be improved and whether the site of data collection influenced the results. A questionnaire was piloted, then distributed and collected through branches of the British Epilepsy Association, general practice and secondary care clinics. Data collected were both quantitative and qualitative. One hundred and seventy-eight questionnaires were collected from three sources. The responders were a severe seizure group. Structured care in general practice was uncommon with 54% being seen only when needed. Dose and type of antiepileptic medication was rarely altered in general practice. Information about their condition was given to 44% of the responders by their GP. Sixty-one percent would prefer their epilepsy care to be 'shared' between primary and secondary services. The majority of patients were satisfied with GP services, felt they could easily discuss their epilepsy, but 58% felt they 'rarely' or 'never' received enough information about their condition in general practice. Satisfaction with GP care varied, dependent on where the data were collected. Patients would value more information and more time to discuss the effects of their epilepsy. In conclusion general practice care for epilepsy is still reactive. Patients value more information and more time to discuss implications. The data collection point affects the results; any conclusions about the organisation of epilepsy care should draw data from community patient samples.

Managing epilepsy in general practice: the dissemination and uptake of a free audit package, and collated results from 12 practices in England and Wales

This study aimed to assess the uptake and use by general practitioners of a free epilepsy audit protocol, and describe the care provided by practices which returned completed audits. A protocol for epilepsy audit in general practice was designed and described in the medical press. Practices were invited to reply. Responders were provided with the protocol. A total of 215 practices responded to the articles in the press. Questionnaires asking how they had used the audit protocol were sent to them 18 months later. One hundred and seventy (79%) of the 215 responding practices returned the questionnaires. Forty-seven (28%) had collected some or all of the data. Twenty-two (13%) submitted data of which 12 (7%) matched the original protocol. Aggregated list sizes for these 12 practices was 75689 and 502 (0.66%) patients were being treated. Of these, 60% were seizure free and 11% were having more than one seizure per month. Seventy-one were receiving monotherapy and only two patients were taking more than three drugs. Eighty-eight per cent of patients still having seizures had been seen by their GP for their epilepsy in the last 12 months. In 18% of cases, information on epilepsy lifestyle issues had been given and noted. Offering a free epilepsy audit package can stimulate interest amongst practices in the topic and resulted in 13% collecting and submitting their data for analysis. Practices reported a higher prevalence for epilepsy (0.66%) than in previous studies. The majority of patients with active epilepsy (88%) had been seen by a general practitioner in the last 12 months. Most (71%) were receiving monotherapy, but recording of seizure frequency and provision of information about epilepsy was low.

Generic prescribing for epilepsy. Is it safe?

Generic prescribing for epilepsy remains controversial. This study aimed to ascertain if a change occurred in the incidence of seizures or side-effects when a different pharmaceutical manufacturer's version of the same antiepileptic drug was taken (a 'switch'). Forty general practices with a list size of 350 168 were recruited. They identified 2285 people being treated for epilepsy with either carbamazepine, phenytoin or sodium valproate. A questionnaire was sent to the people with epilepsy. Those who recalled taking a different pharmaceutical manufacturer's supply of the same antiepileptic drug over the last 2 years were interviewed by their practice if they reported a problem with the control of their epilepsy after a 'switch'. One thousand, three hundred and thirty-three (58.8%) people with epilepsy responded: 251 (18.7%) had experienced a 'switch', 27 (10.8%) reported 'validated' problems; 25 (9.9%) reported unproven problems; 22 (8.8%) reported problems, but follow-up was incomplete; 177 (70.5%) reported no problems. This study suggests that money saved by generic prescribing is outweighed by negative health gain for the person with epilepsy, increased work in general practice, and increased social costs.

Correlates of employment history and employability in a British epilepsy sample

This study examined the inter-relationships between employment status, employment experiences, background, educational and epilepsy-related variables in a community sample of 1709 people with epilepsy in England and Wales. A postal questionnaire yielded information which included attitudes to careers advice, experiences with fellow employees and management when in work, experiences of being questioned about epilepsy, and the perceived effect of having epilepsy on employment prospects. In a principal components analysis, a factor of 'employability' was identified that had high loadings for educational qualifications, socioeconomic status and employment history. Good employability was found to be related to perceptions that epilepsy had little or no effect on job prospects, good experiences with work colleagues and management, low seizure severity and good seizure control. Further data analyses which focused on people's actual employment histories confirmed the importance of past experiences in employment, educational qualifications, seizure severity and seizure frequency for distinguishing between groups. The study findings are discussed and, taken together, they imply that quality of medical care, employability and good employment history are interconnected in important ways.

Plasma epinephrine appearance and clearance rates in fetal and newborn sheep

Newborn plasma catecholamine levels are elevated compared to fetal life. Whether this reflects increased catecholamine secretion after birth or decreased clearance is not known. To determine the plasma appearance and clearance rates for catecholamines during the transition to postnatal life, we compared plasma epinephrine appearance and clearance rates in fetal sheep before birth and in newborns after delivery. Plasma epinephrine appearance and clearance rates were measured by radiotracer analysis in eight fetuses at 127 +/- 1 days of gestation and, after cesarean delivery, at 130 +/- 1 days of gestation. There was no difference in plasma epinephrine appearance rate during the fetal (26 +/- 4 ng.kg-1 x min-1) or newborn studies (31 +/- 5 ng.kg-1 x min-1). The fetal plasma epinephrine clearance rate (131 +/- 13 ml.kg-1 x min-1) was significantly higher than newborn plasma epinephrine clearance rate (40 +/- 3 ml.kg-1 x min-1). Thus fetal plasma epinephrine appearance rate is not different from appearance rate in the immediate newborn period when catecholamine levels are higher than during most other physiological circumstances. The increase in circulating catecholamine levels at birth is due in part to a significant decrease in clearance rate. It is likely that removal of the placental contribution to whole body clearance accounts for much of the difference observed in fetal and newborn clearance rates.

Effects of fetal growth retardation on the development of central and peripheral catecholaminergic pathways in the sheep

Regional norepinephrine and dopamine content and cerebral alpha 1- and beta-adrenergic receptor mechanisms were studied in the brain of sham operated control and single umbilical artery ligation (SUAL) induced growth retarded newborn sheep. Brain sparing was evidenced by relative preservation of brain weight compared to other organ systems. Norepinephrine and dopamine content of the brain were not affected by SUAL. This is in contrast to decreased norepinephrine levels in the brown fat, a normally densely innervated peripheral tissue. Alpha 1- and beta-adrenergic receptor numbers and affinity states were similar between the two groups. Coupling between beta-receptor and guanine nucleotide stimulatory protein and agonist stimulated adenylyl cyclase activity were unaffected by SUAL. Brain regional DNA content and protein/DNA ratios were not different between the two groups. These data suggest that single umbilical artery ligation induced fetal growth retardation modifies peripheral but not central catecholaminergic pathways in the sheep. Both growth and expression of specific catecholaminergic signal transduction system are protected in the brain.

Single umbilical artery ligation-induced fetal growth retardation: effect on postnatal adaptation

To assess whether prolonged intrauterine stress and resultant fetal growth retardation result in depletion of adrenal catecholamines and alter the adrenergic signal transduction system, we studied newborn sheep after single umbilical artery ligation (SUAL)-induced growth retardation. The animals were delivered at term, and postnatal cardiovascular, pulmonary, endocrine, and metabolic responses were measured. We also evaluated the status of myocardial and pulmonary beta-adrenergic receptor number and function. SUAL caused significant growth retardation but relative preservation of brain and adrenal gland weight and adrenal catecholamine content. Blood pressure, plasma free fatty acid, and glucose responses at birth were blunted in SUAL animals. The plasma epinephrine (Epi) and norepinephrine levels were comparable in both groups for the first 2 h of age. By 4 h, both plasma concentration and plasma appearance rate of Epi were reduced to 40% of control in SUAL animals (P less than 0.05). Neither beta-receptor density, affinity, nor adenylate cyclase activity were altered by SUAL in either cardiac or pulmonary membranes. These results suggest that, rather than overt depletion, there is relative sparing of initial adrenal medullary function that later waned. This response and preservation of the beta-adrenergic signal transduction system may represent partial compensation for the physiological stress induced by SUAL.

Free and sulfoconjugated catecholamine responses at birth in newborn sheep

There have been little data on catecholamine sulfoconjugation in developing animals or humans. We studied the differences in free and sulfoconjugated catecholamines at birth in newborn sheep. Baseline concentrations of sulfoconjugated norepinephrine and epinephrine were the predominant form of circulating catecholamine, representing 77 +/- 4 and 65 +/- 12% of total circulating catecholamines, respectively. At birth the free epinephrine concentration increased 10-fold (49 +/- 27 to 653 +/- 21 pg/ml, respectively), and plasma free norepinephrine concentration rose 4-fold (307 +/- 92 to 1,178 +/- 389 pg/ml). In contrast, there was only a transient twofold increase in the sulfoconjugated epinephrine. There was no increase in the sulfoconjugated form of norepinephrine. These data demonstrate that, while the near-term newborn sheep has a well-developed mechanism for sulfoconjugation of circulating catecholamines, this does not occur rapidly. During the logarithmic increases of circulating catecholamines at birth, there are not commensurate increases in the concentration of sulfoconjugated norepinephrine or epinephrine. Thus sulfoconjugation does not appear to represent a significant mechanism for inactivation of the high circulating levels of catecholamines seen at birth.

Epilepsy: patient views on their condition and treatment

To determine how patients with epilepsy feel about their condition, their current medication and their treatment, a mail survey was conducted among a random selection of 800 members of the British Epilepsy Association (BEA). Completed questionnaires were received from 437 members (55% response rate). This high response rate, achieved over a 4-week period, indicates great concern about their condition among the membership sampled. The majority of patients (80%) were adults; 20% were 18 years or younger. Some 72% of patients experienced one or less seizures per month and 52% were employed. Comments from an open-ended question about treatment indicated that respondents would like to see an increase in the provision of services and in the information conveyed (a more interactive communication between the patient and the physician); both issues should improve the emotional support provided by physicians. Positive feelings about medications were reported when seizures were controlled, although unhappiness was expressed with the length of time and varying doses that had to be taken before a 'correct' dosage level was established. Also expressed was a concern about the extent of management and of experimentation with medication left to the patient and care-giver. Opportunities exist for greater communication among physician, patient and care-givers to ease the feeling of frustration, discouragement and isolation seen with a condition which affects 2 to 3% of individuals during their lifetime.

Maturational changes in expression of enkephalin peptides in adrenal and extra-adrenal tissue of fetal and adult rabbits

Met-enkephalin immunoreactivity (MET-ENKi), total enkephalin immunoreactivity (TOTAL MET-ENKi) and catecholamines were measured in adrenal and extra-adrenal tissue of fetal, newborn and adult rabbits. Met-enkephalin peptides were detected in adrenal and extra-adrenal tissue by 29 days of gestation. There were progressive increases in TOTAL MET-ENKi in both the adrenal and extra-adrenal tissue during development. In 29-day-old fetuses, MET-ENKi represented 43 and 50% of the peptide content in adrenal and extra-adrenal tissues respectively. By 3 days after birth, MET-ENKi represented only 15 and 7% of the peptide content in the same tissues. In the adult adrenals, 10% of enkephalin peptides were found as MET-ENKi. There were progressive increases in adrenal and extra-adrenal catecholamine content in the fetal and newborn rabbits throughout development. The changes in the ratio of MET-ENKi to TOTAL MET-ENKi peptides suggest differences in posttranslational processing of proenkephalin peptide during maturation. We speculate that enkephalin peptides derived from proenkephalin A are important during fetal and early newborn life and that extra-adrenal tissue may be an important source of these peptides during development.

Cardiovascular effects of SKF 104078 in lambs

We studied the effects of SKF 104078 in anesthetized, newborn lambs and compared it to nonspecific alpha-receptor blockade by tolazoline. SKF 104078 infusion decreased pulmonary and systemic arterial pressures in newborn lambs when infused during normoxic ventilation. When infused during hypoxia, SKF 104078 decreased cardiac output and systemic blood pressure without affecting pulmonary pressure. Due to the predominance of systemic effects, the usefulness of SKF 104078 in states of hypoxic pulmonary vasoconstriction is limited.