Intramuscular administration of ACTH1-24 vs. 24-hour blood sampling in the assessment of adrenocortical function

The standard intravenous short Synacthen test (SSST) has long been accepted as one of the most reliable diagnostic tests of adrenocortical insufficiency. Intramuscular (i.m.) administration of ACTH obviates the need of venous cannulation and can be used as an alternative to the intravenous test. Nevertheless, reports of correlation between cortisol response to i.m. ACTH1-24 and 24-hr average cortisol concentration are scarce. We studied this relation in 64 nonobese healthy men. Blood samples for serial cortisol measurements were collected hourly over 24 hrs. The following day, blood samples were collected at baseline and at 30 and 60 min after intramuscular (i.m.) administration of 250 microg of ACTH1-24. All healthy men reached 24-hr serum cortisol peak values (Cmax) between 0600 h and 1000 h. Following i.m. ACTH1-24, cortisol levels significantly increased at both 30 (C30ACTH) and 60 (C60ACTH) minutes, when compared to baseline values. C30ACTH and C60ACTH significantly correlated with Cmax and with the 24-hr time-integrated cortisol concentration (AUC0-24). Morning mean cortisol was calculated as the average of serum concentrations measured between 0600 h and 1000 h (C(av)6-10) and correlated very well with AUC0-24. In conclusion, we confirmed that i.m. administration of ACTH1-24, followed by a single blood sampling at 60 min for cortisol measurement represents a valid, convenient and cost- effective screening test of adrenal function.     

Partitioning of limiting protein and energy in the growing pig: description of the problem, possible rules and their qualitative evaluation

A core part of any animal growth model is how it predicts the partitioning of dietary protein and energy to protein and lipid retention for different genotypes at different degrees of maturity. Rules of partitioning need to be combined with protein and energy systems to make predictions. The animal needs describing in relation to its genotype, live weight and, possibly, body composition. Some existing partitioning rules will apply over rather narrow ranges of food composition, animal and environment. Ideally, a rule would apply over the whole of the possible experimental space (scope). The live weight range over which it will apply should at least extend beyond the 'slaughter weight range', and ideally would include the period from the start of feeding through to maturity. Solutions proposed in the literature to the partitioning problem are described in detail and criticised in relation to their scope, generality and economy of parameters. They all raise the issue, at least implicitly, of the factors that affect the net marginal efficiency of using absorbed dietary protein for protein retention. This is identified as the crucial problem to solve. A problem identified as important is whether the effects of animal and food composition variables are independent of each other or not. Of the rules in the literature, several could be rejected on qualitative grounds. Those rules that survived were taken forward for further critical and quantitative analysis in the companion paper.     

Differential immunogenicity of HLA mismatches in clinical transplantation

Although HLA matching is beneficial in clinical transplantation, it is not feasible to select a completely HLA matched donor for every potential recipient because of the enormous polymorphism of the HLA system. As a consequence, the majority of the recipients will be transplanted with a mismatched donor organ or hematopoietic stem cell transplant. For this large group of patients it is important to take advantage of the differential immunogenicity of HLA mismatches and to select for them a donor with HLA mismatches of low immunogenicity, the so-called acceptable mismatches. The differential immunogenicity of HLA mismatches can be determined by either retrospective analysis of graft survival data or by in vitro assays measuring T-cell and B-cell alloreactivity. A recently developed computer algorithm (HLAMatchmaker) can be instrumental in selecting donors with HLA mismatches, which do not lead to alloantibody formation. The theoretical background and practical implications of this acceptable mismatch approach are discussed.     

Evaluation and treatment of Cushing's syndrome

Cushing’s syndrome results from sustained pathologic hypercortisolism caused by excessive corticotropin (ACTH) secretion by tumors in the pituitary gland (Cushing’s disease, 70%) or elsewhere (15%), or by ACTH-independent cortisol secretion from adrenal tumors (15%). The clinical features are variable, and no single pattern is seen in all patients. Those features most specific for Cushing’s syndrome include abnormal fat distribution, particularly in the supraclavicular and temporal fossae, proximal muscle weakness, wide purple striae, and decreased linear growth with continued weight gain in a child. Patients with characteristics of glucocorticoid excess should be screened with measurements of saliva or urine cortisol or dexamethasone suppression testing. The diagnosis of Cushing’s syndrome should be followed by the measurement of plasma ACTH concentration to determine whether the hypercortisolism is ACTH-independent. In ACTH-dependent patients, bilateral inferior petrosal sinus sampling with measurement of ACTH before and after administration of ACTH-releasing hormone most accurately distinguishes pituitary from ectopic ACTH secretion. Surgical resection of tumor is the optimal treatment for all forms of Cushing’s syndrome; bilateral adrenalectomy, medical treatment, or radiotherapy are sought in inoperable or recurrent cases. The medical treatment of choice is ketoconazole. The prognosis is better for Cushing’s disease and benign adrenal causes of Cushing’s syndrome than adrenocortical cancer and malignant ACTH-producing tumors.     

Comparative study of plasma ghrelin levels in women with polycystic ovary syndrome, in hyperandrogenic women and in normal controls

BACKGROUND: Ghrelin is a novel peptide associated with energy balance, obesity, and perhaps gonadal function. The present study was designed in order: (i) to compare plasma ghrelin levels between women with PCOS, women who presented only with hyperandrogenaemia and healthy controls; and (ii) to investigate the relationship between circulating ghrelin and the heterogeneity of clinical and biochemical manifestations of PCOS. METHODS: Two hundred and fifty-nine women with PCOS, 25 women who had only hyperandrogenaemia and 46 controls, were studied. Women with PCOS were further divided, based on the presence of chronic anovulation, biochemical hyperandrogenaemia, clinical hyperandrogenism, and polycystic ovary morphology on ultrasound evaluation. In all women, the basal levels of gonadotrophins, androgens, 17-OH-progesterone, sex hormone-binding globulin, glucose, insulin and ghrelin were measured. RESULTS: Women with PCOS had lower ghrelin levels, compared to both women with hyperandrogenaemia and controls; women with hyperandrogenaemia had lower ghrelin levels, compared to controls, but not significantly so. While PCOS-associated hyperandrogenaemia was inversely related to ghrelin levels, anovulation and polycystic ovary morphology were associated with higher concentrations. Ghrelin levels were negatively correlated with 17-OH-progesterone levels. CONCLUSIONS: In PCOS, circulating ghrelin and androgens are inversely related and it is possible that this peptide is involved in steroidal synthesis and/or action. It is also likely that different clinical and biochemical manifestations of the syndrome are also associated with different ghrelin concentrations.     

Behaviour of food restricted broilers during rearing and lay--effects of an alternative feeding method

Broiler breeders are subjected to quantitative food restriction in order to control their growth, and this restriction is particularly severe during rearing. While such restriction improves some welfare problems associated with ad libitum feeding, it causes others: birds routinely show abnormal oral behaviours and have elevated plasma corticosterone concentration (PCC) and changes in white blood cell counts (WBCs). The aim of this study was to examine if feeding birds qualitatively restricted diets ad libitum during rearing could reduce signs of impaired welfare, as judged by behaviour and blood indices of stress, while also meeting commercially desired growth rates and uniformity. Furthermore, we examined what carry-over effects such a feeding method had on birds in the laying phase when all birds were fed on a conventional quantitative restriction regime. During rearing (1-20 weeks of age), pens of birds were either fed limited amounts of standard basal diets (Control, i.e. quantitative restriction), or ad libitum diets consisting of standard basal diets with gradually increasing levels of calcium propionate (CaP) and a constant level of oat hulls (OH), designated CaP + OH (i.e. qualitative restriction). Results showed that, during rearing, weights and weight uniformity were similar for the two groups. During feeding motivation tests, Control birds always consumed more food than CaP + OH birds. This suggests that Control birds were more highly motivated to feed than CaP + OH birds, although care has to be taken in interpreting these results. Treatment did not affect PCCs or WBCs, but there was a general decline in PCCs with bird age. All reported behaviours differed significantly between treatment groups during rearing, but disappeared during lay when all birds were fed a similar amount of food. Control birds spent up to 50% of time in object pecking during rearing periods, but this behaviour was virtually non-existent in birds in the qualitative feeding regime. Overall, the results indicate that broiler breeders can be successfully limited in growth rates by qualitative food restriction and this results in significant changes of behaviour that suggest improvements to bird welfare.     

Aberrant deltaPKC activation in the spinal cord of Wobbler mouse: a model of motor neuron disease

Protein kinase C (PKC) was suggested to play a role in the pathology of amyotrophic lateral sclerosis (ALS) patients. Activation of PKC delta (deltaPKC) modulates mitochondrially induced apoptosis. The goal of the present study was to define whether deltaPKC activation occurs in Wobbler mouse spinal cord (a model of motor neuron disease). The level of deltaPKC in the soluble fraction was significantly decreased in the spinal cord of Wobbler mice, which was associated with a significant increase in deltaPKC cleavage. Since caspase-3 is known to cleave deltaPKC, we determined caspase-3 activation in the Wobbler mice spinal cord, immunohistochemically. The results demonstrated intense immunoreactivity for activated caspase-3 in corticospinal tract motor neurons of Wobbler mice spinal cord. We hypothesize from these results that caspase-3 activation cleaves deltaPKC, which in turn promotes an aberrant signal transduction pathway in the Wobbler spinal cord.     

Effects into adulthood of single or repeated antenatal corticosteroids in sheep

OBJECTIVE: To determine effects of maternal or fetal injections of betamethasone on postnatal growth and arterial pressure. STUDY DESIGN: We measured body weight, arterial pressure, and heart rate serially in sheep born after single or repeated maternal or fetal betamethasone injections. At approximately 3.5 years, organ weights were measured. RESULTS: Repeated maternal betamethasone injections caused intrauterine growth restriction, and low body weight and blood pressure at 3 months. From 6 months to 3 years, body weight, blood pressure, and heart rate were not affected by treatment. At approximately 3.5 years, brain weight was reduced after single or repeated maternal betamethasone by 13% and 18%, respectively (P = .001). Fetal betamethasone reduced brain weight by 7% to 8% (P = .018). Weights of other organs were not affected by treatment. Brain weight was unrelated to body weight at approximately 3.5 years (P = .649) but was related to birth weight (P = .029). CONCLUSION: Prenatal betamethasone does not have long-term effects on blood pressure but causes a persistent deficit in brain weight.     

Assessment of the enhancement in predictive accuracy provided by systematic biopsy in predicting outcome for clinically localized prostate cancer

PURPOSE: Current localized prostate cancer treatment outcome nomograms rely on prostate specific antigen (PSA), tumor stage and grade. We investigated whether the addition of prostate biopsy features may enhance the accuracy of a nomogram predicting recurrence after radical prostatectomy (RP). MATERIALS AND METHODS: Clinical data from 1,152 patients who underwent RP were used and included PSA, clinical stage, biopsy Gleason grade and systematic biopsy information that quantified the amount of cancer and high grade cancer. Predictive accuracy for freedom from recurrence after RP was assessed with and without tumor quantification in the biopsy by the area under the receiver operating characteristics curve (AUC). RESULTS: Percentage and number of cores with cancer, and percentage and number of cores with high grade cancer were predictors of outcome when added to models that included PSA, Gleason grade and clinical stage (all p <0.0001). Nomogram accuracy with 3 traditional variables (AUC 0.790) was minimally enhanced with the addition of percentage or number of positive cores (AUC 0.804 and 0.800, respectively), or percentage or number of cores with high grade cancer (AUC 0.802 and 0.800, respectively). Maximum predictive accuracy of 0.811 was achieved after supplementing the traditional 3-variable nomogram with various combinations of additional pathological predictors. CONCLUSIONS: The information provided by systematic biopsies substantially improves the ability to predict outcome following RP. However, some incremental predictive accuracy was achieved by adding systematic biopsy features.     

HLAMatchmaker-based strategy to identify acceptable HLA class I mismatches for highly sensitized kidney transplant candidates

HLAMatchmaker determines HLA compatibility at the level of polymorphic amino acid triplets in antibody-accessible sequence positions. Recent studies have shown that among HLA-DR-matched kidney transplants, the HLA-A,B antigen mismatches which are compatible at the triplet level have almost identical graft survival rates as the zero-HLA-A,B antigen mismatches. This finding provides the basis of a new strategy to identify HLA-mismatched organs that have similar success rates as the zero-HLA-antigen mismatches. This report describes how in conjunction with the Acceptable Mismatch program in Eurotransplant, HLAMatchmaker can expand the pool of potential donors for highly sensitized patients, for whom it is very difficult to find a compatible transplant. Sera from 35 highly sensitized kidney transplant candidates with an average PRA of 96% were screened by lymphocytotoxicity with HLA-typed panels that included cells that were selectively mismatched for one or two HLA antigens for each patient. Acceptable and unacceptable HLA-A,B antigen mismatches were determined from the serum reactivity with the cell panel. HLAMatchmaker analysis was applied to identify additional HLA class I antigens that were matched at the triplet level. For each patient, we calculated the probability of finding a donor (PFD) in the different match categories from HLA gene frequencies in the kidney donor population. The median PFD for a zero-antigen mismatch was 0.025%. Matching at the triplet level increased the median PFD to 0.037% (P=0.008). The median PFD was 0.058% for a 0-1-triplet mismatch and 0.226% for a 0-2-triplet mismatch. Serum screening identified acceptable antigen mismatches for 28 of 35 highly sensitized patients, and the median PFD increased to 0.307% for a zero/acceptable antigen mismatch. The application of HLAMatchmaker permitted for 33 patients (or 92%) the identification of additional antigens that were acceptable at the triplet level, and the median PFD for a zero/acceptable triplet mismatch went up to 0.425%. Inclusion of one-triplet mismatches increased the median PFD to 1.112%. Validation studies have shown that patient sera reacted with none of the zero-triplet-mismatched antigens, 8-13% of the one-triplet mismatches, and 12-19% of the two-triplet mismatches. Although most antigens with one or two mismatched triplets appear acceptable to highly sensitized patients, a serum analysis must ascertain that the patient's antibodies do not recognize such mismatched triplets. HLAMatchmaker offers a useful strategy of identifying more donors with acceptable HLA mismatches and could alleviate the problem of accumulation of highly sensitized patients on the transplant waiting list.