A clinical-pharmaceutical medication reconciliation with patient interview for a medication review to identify drug-related problems in elective patients during hospital admission.

Background and aim: Drug-related problems (DRPs), e.g.drug-drug interactions (DDI), can lead to adversedrug reactions (ADRs) and thus complications during hospitalization. For this reason, such DRP, DDI and ADR should be identified and characterized as early as possible during hospital admission. We aimed to perform a clinical-pharmaceutical medication reconciliation in which patient-related information was collected and compared to drug-related information in a medication review. Investigations: During a 24-week-period, we consecutively invited patients electively admitted to Urology, Otolaryngology, Oral and Maxillofacial Surgery, General and Visceral Surgery, and Oncology Departments of a 300-bed hospital. A clinical pharmacist performed a patient interview asking for medication, ADR, and adherence. The medication reconciliation considered packages for a brown-bag analysis, medication lists, and data from the clinical information-system (CIS). In a medication review, we matched patient-related information to drug-related information from the drug label, guidelines, drug-databases and websites to identify DRPs. Results: In the study, 356 patients (median age: 58 years) taking 1,712 drugs participated. Of all patients, 7.3% reported ADR and 10.7% missing adherence. 5.3% brought packages that enabled a brown-bag analysis and 21.1% a medication list. In 76.7% of patients, information from CIS was incomplete or not up-to-date. Among the most frequently identified DRPs were "Medication without diagnosis" (31.2%) and "Inappropriate timing of administration" (11.5%). The proportion of patients affected by severe DDI ranged from 0.8%-16.6%, depending on the drug information source. Conclusions: Incomplete patient data, frequently identified DRPs and inconsistent drug-based information make pharmaceutical involvement in medication reconciliation on admission a necessity.

Impact of Covid-19 on farming systems in Europe through the lens of resilience thinking.

Context: Resilience is the ability to deal with shocks and stresses, including the unknown and previously unimaginable, such as the Covid-19 crisis. Objective: This paper assesses (i) how different farming systems were exposed to the crisis, (ii) which resilience capacities were revealed and (iii) how resilience was enabled or constrained by the farming systems' social and institutional environment. Methods: The 11 farming systems included have been analysed since 2017. This allows a comparison of pre-Covid-19 findings and the Covid-19 crisis. Pre-Covid findings are from the SURE-Farm systematic sustainability and resilience assessment. For Covid-19 a special data collection was carried out during the early stage of lockdowns. Results and conclusions: Our case studies found limited impact of Covid-19 on the production and delivery of food and other agricultural products. This was due to either little exposure or the agile activation of robustness capacities of the farming systems in combination with an enabling institutional environment. Revealed capacities were mainly based on already existing connectedness among farmers and more broadly in value chains. Across cases, the experience of the crisis triggered reflexivity about the operation of the farming systems. Recurring topics were the need for shorter chains, more fairness towards farmers, and less dependence on migrant workers. However, actors in the farming systems and the enabling environment generally focused on the immediate issues and gave little real consideration to long-term implications and challenges. Hence, adaptive or transformative capacities were much less on display than coping capacities. The comparison with pre-Covid findings mostly showed similarities. If challenges, such as shortage of labour, already loomed before, they persisted during the crisis. Furthermore, the eminent role of resilience attributes was confirmed. In cases with high connectedness and diversity we found that these system characteristics contributed significantly to dealing with the crisis. Also the focus on coping capacities was already visible before the crisis. We are not sure yet whether the focus on short-term robustness just reflects the higher visibility and urgency of shocks compared to slow processes that undermine or threaten important system functions, or whether they betray an imbalance in resilience capacities at the expense of adaptability and transformability. Significance: Our analysis indicates that if transformations are required, e.g. to respond to concerns about transnational value chains and future pandemics from zoonosis, the transformative capacity of many farming systems needs to be actively enhanced through an enabling environment.

Somatic mutation of the MEN1 gene in parathyroid tumours.

Primary hyperparathyroidism is a common disorder with an annual incidence of approximately 0.5 in 1,000 (ref. 1). In more than 95% of cases, the disease is caused by sporadic parathyroid adenoma or sporadic hyperplasia. Some cases are caused by inherited syndromes, such as multiple endocrine neoplasia type 1 (MEN1; ref. 2). In most cases, the molecular basis of parathyroid neoplasia is unknown. Parathyroid adenomas are usually monoclonal, suggesting that one important step in tumour development is a mutation in a progenitor cell. Approximately 30% of sporadic parathyroid tumours show loss of heterozygosity (LOH) for polymorphic markers on 11q13, the site of the MEN1 tumour suppressor gene. This raises the question of whether such sporadic parathyroid tumours are caused by sequential inactivation of both alleles of the MEN1 gene. We recently cloned the MEN1 gene and identified MEN1 germline mutations in fourteen of fifteen kindreds with familial MEN1 (ref. 10). We have studied parathyroid tumours not associated with MEN1 to determine whether somatic mutations in the MEN1 gene are present. Among 33 tumours we found somatic MEN1 gene mutation in 7, while the corresponding MEN1 germline sequence was normal in each patient. All tumours with MEN1 gene mutation showed LOH on 11q13, making the tumour cells hemi- or homozygous for the mutant allele. Thus, somatic MEN1 gene mutation for the mutant allele. Thus, somatic MEN1 gene mutation contributes to tumorigenesis in a substantial number of parathyroid tumours not associated with the MEN1 syndrome.

Adverse events following vaccination in the French armed forces: An overview of surveillance conducted from 2002 to 2010.

French military personnel are subject to a compulsory vaccination schedule. The aim of this study was to describe vaccine adverse events (VAE) reported from 2002 to 2010 in armed forces. VAE are routinely surveyed by the military Centre for epidemiology and public health. For each case, military practitioners fill a notification form, providing patient characteristics, clinical information and vaccines administered. For this study, VAE following influenza A(H1N1)pdm09 vaccination were excluded. Among the 473 cases retained, 442 (93%) corresponded to non-severe VAE,including local, regional and systemic events, while 31 corresponded to severe VAE, with two leading to significant disability. The global VAE reporting rate (RR) was 14.0 per 100,000 injections. While stationary from 2002 to 2008, the RR increased from 2009. The most important observations were a marked increase of VAE attributed to Bacillus Calmette-Guérin (BCG) vaccine from 2005 to 2008, a high RR observed with the inactivated diphtheria-tetanus (toxoids)-poliovirus vaccine combined with acellular pertussis vaccine (dTap-IPV) from 2008 and an increase in RR for seasonal influenza vaccine VAE in 2009. Our RR for severe VAE (1.1 VAEper 100,000) appears comparable with rates observed among United States civilians and military personnel. The increase observed from 2009 could be partly explained by the influenza A(H1N1)pdm09 pandemic which increased practitioner awareness towards VAE. In conclusion, the tolerance of the vaccines used in French armed forces appears acceptable.

G proteins in cellular control.

In the past year, cDNA cloning has revealed substantial diversity in G protein alpha, beta and gamma subunits. The number of cellular functions recognized to be controlled by G proteins is also increasing. Most G proteins are associated with the cytoplasmic surface of the plasma membrane, and molecular mechanisms for membrane association of certain G protein subunits have been defined recently. Mutations in G protein subunits, both artificially induced and naturally occurring, have provided important insights into G protein structure and function.

International Standardized Nomenclature for Outbred Stocks of Laboratory Animals.

In accordance with the «Aims of ICLA¼ (ICLA Bulletin No. 26, March 1970) the Governing Board established in 1969 a Working Party to prepare an International Nomenclature System for Outbred Animals. The members were: Professor, Dr. A. Spiegel, Federal Republic of Germany, chairman.Dr. M. Festing, United KingdomDr. K. Kondo, JapanDr. R. Loosli, SwitzerlandMr. S. Poiley, U.S.A. The nomenclature rules, completed and approved by the ICLA Governing Board on 8 December 1971, are published herewith. I am convinced that this system will bring order out of the existing chaos. The system is an offer to the world laboratory animal science, particularly the breeders and users. Editors of scientific journals, catalogues, and indices all over the world are also encouraged to require and use animal stock identification by this system for outbred animals used in experimentation. The ICLA Governing Board would have preferred to have seen an international centralization of symbol registration. However, the ICLA Secretariat has not got the capacity necessary for such a task and some practical solution to the registration problem will have to be found by the Governing Board. A final aim should then be for ICLA to publish a comprehensive world list of breeder symbols at intervals. Oslo, January 1972 Stian Erichsen  Secretary-General.

Protein kinase A and protein kinase C(alpha)/PPP1CC2 play opposing roles in the regulation of phosphatidylinositol 3-kinase activation in bovine sperm.

In order to acquire fertilization competence, spermatozoa have to undergo biochemical changes in the female reproductive tract, known as capacitation. Signaling pathways that take place during the capacitation process are much investigated issue. However, the role and regulation of phosphatidylinositol 3-kinase (PI3K) in this process are still not clear. Previously, we reported that short-time activation of protein kinase A (PRKA, PKA) leads to PI3K activation and protein kinase C(alpha)(PRKCA, PKC(alpha)) inhibition. In the present study, we found that during the capacitation PI3K phosphorylation/activation increases. PI3K activation was PRKA dependent, and down-regulated by PRKCA. PRKCA is found to be highly active at the beginning of the capacitation, conditions in which PI3K is not active. Moreover, inhibition of PRKCA causes significant activation of PI3K. Similar activation of PI3K is seen when the phosphatase PPP1 is blocked suggesting that PPP1 regulates PI3K activity. We found that during the capacitation PRKCA and PPP1CC2 (PP1gamma2) form a complex, and the two enzymes were degraded during the capacitation, suggesting that this degradation enables the activation of PI3K. This degradation is mediated by PRKA, indicating that in addition to the direct activation of PI3K by PRKA, this kinase can enhance PI3K phosphorylation indirectly by enhancing the degradation and inactivation of PRKCA and PPP1CC2.

Amino- and carboxy-terminal deletion mutants of Gs alpha are localized to the particulate fraction of transfected COS cells.

To elucidate the structural basis for membrane attachment of the alpha subunit of the stimulatory G protein (Gs alpha), mutant Gs alpha cDNAs with deletions of amino acid residues in the amino and/or carboxy termini were transiently expressed in COS-7 cells. The particulate and soluble fractions prepared from these cells were analyzed by immunoblot using peptide specific antibodies to monitor distribution of the expressed proteins. Transfection of mutant forms of Gs alpha with either 26 amino terminal residues deleted (delta 3-28) or with 59 amino terminal residues deleted (delta 1-59) resulted in immunoreactive proteins which localized primarily to the particulate fraction. Similarly, mutants with 10 (delta 385-394), 32 (delta 353-384), or 42 (delta 353-394) amino acid residues deleted from the carboxy terminus also localized to the particulate fraction, as did a mutant form of Gs alpha lacking amino acid residues at both the amino and carboxy termini (delta 3-28)/(delta 353-384). Mutant and wild type forms of Gs alpha demonstrated a similar degree of tightness in their binding to membranes as demonstrated by treatment with 2.5 M NaCl or 6 M urea, but some mutant forms were relatively resistant compared with wild type Gs alpha to solubilization by 15 mM NaOH or 1% sodium cholate. We conclude that: (a) deletion of significant portions of the amino and/or carboxyl terminus of Gs alpha is still compatible with protein expression; (b) deletion of these regions is insufficient to cause cytosolic localization of the expressed protein. The basis of Gs alpha membrane targeting remains to be elucidated.

Mediation of growth factor induced DNA synthesis and calcium mobilization by Gq and Gi2.

A newly identified subclass of the heterotrimeric GTP binding regulatory protein family, Gq, has been found to be expressed in a diverse range of cell types. We investigated the potential role of this protein in growth factor signal transduction pathways and its potential relationship to the function of other G alpha subclasses. Recent biochemical studies have suggested that Gq regulates the beta 1 isozyme of phospholipase C (PLC beta 1), an effector for some growth factors. By microinjection of inhibitory antibodies specific to distinct G alpha subunits into living cells, we have determined that G alpha q transduces bradykinin- and thrombin-stimulated intracellular calcium transients which are likely to be mediated by PLC beta 1. Moreover, we found that G alpha q function is required for the mitogenic action of both of these growth factors. These results indicate that both thrombin and bradykinin utilize Gq to couple to increases in intracellular calcium, and that Gq is a necessary component of the mitogenic action of these factors. While microinjection of antibodies against G alpha i2 did not abolish calcium transients stimulated by either of these factors, such microinjection prevented DNA synthesis in response to thrombin but not to bradykinin. These data suggest that thrombin-induced mitogenesis requires both Gq and Gi2, whereas bradykinin needs only the former. Thus, different growth factors operating upon the same cell type use overlapping yet distinct sets of G alpha subtypes in mitogenic signal transduction pathways. The direct identification of the coupling of both a pertussis toxin sensitive and insensitive G protein subtype in the mitogenic pathways utilized by thrombin offers an in vivo biochemical clarification of previous results obtained by pharmacologic studies.

Subceliular Localization of Inorganic Ions in Plant Cells by in vivo Precipitation.

Uptake of iodide (as a possible tracer of chloride) by barley roots preloaded with thallium (as a tracer of potassium) resulted in in vivo precipitation of the almost insoluble yellow thallium iodide. Electron microscopic observation revealed in several cells a dense precipitate of thallium iodide within the cisternae of the endoplasmic reticulum, which suggests that this membrane system is involved in intracellular ion transport.

Detection of alpha-transducin in retinal rods but not cones.

The distribution in chicken retina of the alpha subunit of transducin, the guanine nucleotide--binding protein that couples light-dependent activation of rhodopsin with activation of guanosine 3',5'-monophosphate phosphodiesterase, was determined with the aid of a specific antiserum. alpha-Transducin was found in rod photoreceptor cells but was not detected in cones. These results show that rods and cones differ with respect to alpha-transducin content and suggest that the processes of phototransduction may differ correspondingly in rods and cones.

Positional cloning of the gene for multiple endocrine neoplasia-type 1.

Multiple endocrine neoplasia-type 1 (MEN1) is an autosomal dominant familial cancer syndrome characterized by tumors in parathyroids, enteropancreatic endocrine tissues, and the anterior pituitary. DNA sequencing from a previously identified minimal interval on chromosome 11q13 identified several candidate genes, one of which contained 12 different frameshift, nonsense, missense, and in-frame deletion mutations in 14 probands from 15 families. The MEN1 gene contains 10 exons and encodes a ubiquitously expressed 2.8-kilobase transcript. The predicted 610-amino acid protein product, termed menin, exhibits no apparent similarities to any previously known proteins. The identification of MEN1 will enable improved understanding of the mechanism of endocrine tumorigenesis and should facilitate early diagnosis.

Community-focused greywater management in two informal settlements in South Africa.

South Africa is struggling to provide services to the millions of poor people migrating to the major centres and living in informal settlements (shanty towns). Whilst the local authorities are generally able to provide potable water from the municipal network to communal taps scattered around the settlements, there is usually inadequate provision of sanitation and little or no provision for the drainage of either stormwater or greywater. This paper describes an investigation into ways of engaging with community structures in the settlements with a view to encouraging "self-help" solutions to greywater management requiring minimal capital investment as an interim "crisis" solution until such time that local and national government is able to provide formal services to everyone. The work was carried out in three settlements encompassing a range of different conditions. Only two are described here. It has become clear that the management of greywater has a low priority amongst the residents of informal settlements. The lack of effective political structures and the breakdown in communication with Ward Councillors and local government officials have contributed to the lack of progress. As the project progressed it became evident that greywater cannot be considered separately from stormwater, sanitation and refuse removal.

The G protein connection: molecular basis of membrane association.

Two distinct types of lipid modification, myristoylation and isoprenylation, are critical for membrane association of heterotrimeric G proteins. Elucidation of the molecular basis for G protein membrane association has important implications for understanding G protein structure and function, and is relevant to potential therapeutic approaches to AIDS and cancer.

Better early outcome with enteral rather than parenteral nutrition in children undergoing MAC allo-SCT.

There is no consensus on the type of nutritional support to introduce in children undergoing allogeneic stem cell transplantation (allo-SCT) after myeloablative conditioning (MAC). This retrospective, multicenter, observational study compared the early administration of enteral nutrition (EN group, n = 97) versus parenteral nutrition (PN group, n = 97) in such patients with matching for important covariates. The primary endpoint was the study of day 100 overall mortality. The early outcome at day 100 was better in EN group regarding mortality rate (1% vs. 13%; p = 0.0127), non relapse mortality (1% vs. 7%; p = 0.066), acute GVHD grades II-IV (37% vs. 54%; p = 0.0127), III-IV (18% vs. 34%; p = 0.0333) and its gut localization (16% vs. 32%; p = 0.0136). Platelet engraftment was better in EN group than in PN group for the threshold of 20 G/L (97% vs. 80% p < 0.0001) and 50 G/L (92% vs. 78%, p < 0.0001). The length of stay was shorter in EN group (28 vs. 52 days, p < 0.0001). There were no differences between the two groups regarding the polynuclear neutrophil engraftment, infection rate or mucositis occurrence. These results suggest that, in children undergoing MAC allo-SCT, PN should be reserved to the only cases when up-front EN is insufficient or impossible to perform.

Deficient guanine nucleotide regulatory unit activity in cultured fibroblast membranes from patients with pseudohypoparathyroidism type I. a cause of impaired synthesis of 3',5'-cyclic AMP by intact and broken cells.

Deficient activity of the guanine nucleotide regulatory protein (G unit), an integral component of the membrane-bound adenylate cyclase complex, has been implicated as the biochemical lesion in many patients with pseudohypoparathyroidism (PHP) type I. In addition to renal resistance to parathyroid hormone in this disorder, there is decreased responsiveness of diverse tissues to hormones that act via 3',5'-cyclic AMP (cAMP). To assess whether a deficiency of G units could account for impaired adenylate cyclase activity, we studied cAMP production in intact cultured fibroblasts and fibroblast plasma membranes from five patients with PHP in response to several activators of adenylate cyclase. The number of G units in PHP fibroblast membranes, measured by cholera toxin-dependent [(32)P]ADP ribosylation of G-unit peptides, as well as the G-unit activity, determined by the ability of detergent extracts to reconstitute adenylate cyclase activity in G-unit-deficient S49 CYC(-) membranes, were found to be markedly reduced compared with control membranes (43 and 40%, respectively), The activation of fibroblast membrane adenylate cyclase by effectors that act directly through the G unit (guanosine triphosphate, guanosine 5'-0-[3-thiotriphosphate] [GTP-gamma-S], NaF) was significantly greater in control membranes than in membranes from patients with PHP. Moreover, we found that hormone (prostaglandin E(1)) stimulated adenylate cyclase activity was also greater in control membranes than in PHP membranes. Neither the apparent affinity of membrane adenylate cyclase for GTP-gamma-S (apparent K(m) =5 X 10(-8) M) nor the rate of enzyme activation by GTP-gamma-S was significantly different in fibroblast membranes from control subjects and patients with PHP. In contrast to the notable differences in hormone and G-unit-activated adenylate cyclase shown in fibroblast membranes from PHP patients and control subjects, the intrinsic catalytic activity of membranes, as determined by forskolin-stimulated adenylate cyclase, was not significantly different in the two groups. Intact fibroblasts derived from patients with PHP accumulated significantly (P 0.001) less cAMP (46+/-21 pmol cAMP/mcg DNA, n = 5) than cells from normal individuals (170+/-51 pmol cAMP/mcg DNA, n = 11) when stimulated with PGE(1). PGE(1)-stimulated accumulation of cAMP by intact fibroblast monolayers correlated closely with PGE(1) plus GTP-activated membrane adenylate cyclase activity in both patients and controls (r = 0.97, P < 0.001). Our data show that, in patients with PHP, (a) fibroblast membranes show a decreased complement of G units, (b) membrane catalytic activity is normal, but adenylate cyclase activity is reduced when stimulated by hormone or by effectors which activate the G unit, (c) the ability of cells to accumulate cAMP in response to hormone stimulation is reduced, and (d) reduced membrane adenylate cyclase activity correlates well with impaired cellular cAMP synthesis. These results, taken together, indicate that a deficiency of G-unit activity can impair synthesis of cAMP by both intact and broken cells, and may explain the resistance of multiple tissues to hormones that act via cAMP observed in PHP.

Deficient adenylate cyclase regulatory protein in renal membranes from a patient with pseudohypoparathyroidism.

Recent studies have established that some patients with pseudohypoparathyroidism have a deficiency of the adenylate cyclase regulatory protein (the G unit) in plasma membranes from erythrocytes, platelets, and fibroblasts. We have directly measured the activity of the G unit in renal membranes from a patient with pseudohypoparathyroidism who, in addition to parathyroid hormone resistance, has resistance to thyrotropin and gonadotropins. Erythrocyte membrane G unit activity was 57% that of control erythrocyte membranes. Lubrol PX extracts of renal membranes had only 30% of the G unit activity of control renal membrane extracts, whether assayed with sodium fluoride or guanosine-5'-O-(3-thiotriphosphate) (GTP-gamma-S). In cholate extracts, the G unit activity was 37 and 48% of control with fluoride or GTP-gamma-S, respectively. Cholera toxin-dependent incorporation of [32P]ADP-ribose into the 42,000-Mr subunit of the G unit was decreased in renal membranes from the patient compared with control renal membranes. The data demonstrate that the membrane G unit deficiency in pseudohypoparathyroidism extends to the cells of a clinically relevant parathyroid hormone target tissue.

Reproduction of human fibrous dysplasia of bone in immunocompromised mice by transplanted mosaics of normal and Gsalpha-mutated skeletal progenitor cells.

We have isolated progenitor cells from the stromal system of the fibrous dysplastic marrow of patients with McCune-Albright Syndrome. Analysis of the Gsalpha gene from individual colonies provided direct evidence for the presence of two different genotypes within single fibrous dysplastic lesions: marrow stromal cells containing two normal Gsalpha alleles, and those containing one normal allele and an allele with an activating mutation. Transplantation of clonal populations of normal cells into the subcutis of immunocompromised mice resulted in normal ossicle formation. In contrast, transplantation of clonal populations of mutant cells always led to the loss of transplanted cells from the transplantation site and no ossicle formation. However, transplantation of a mixture of normal and mutant cells reproduced an abnormal ectopic ossicle recapitulating human fibrous dysplasia and providing an in vivo cellular model of this disease. These results provide experimental evidence for the necessity of both normal and mutant cells in the development of McCune-Albright Syndrome fibrous dysplastic lesions in bone.

Urinary calcium excretion in familial hypocalciuric hypercalcemia. Persistence of relative hypocalciuria after induction of hypoparathyroidism.

Familial hypocalciuric hypercalcemia (FHH) is an autosomal dominant trait comprising hypercalcemia, hypophosphatemia, parathyroid hyperplasia, and unusually low renal clearance of calcium. We evaluated the role of parathyroid hormone in the relative hypocalciuria of FHH and characterized the renal transport of calcium in this disorder using three previously hypercalcemic FHH patients with surgical hypoparathyroidism and three controls with surgical hypoparathyroidism. Intravenous infusion of calcium chloride in two patients with FHH and in three controls increased serum calcium from a mean basal of 5.0 to a mean peak of 6.8 meq/liter in two FHH patients and from 4.2 to 5.7 in three control subjects. Urinary calcium in a third FHH patient was studied without calcium infusion during recovery from hypercalcemia of vitamin D intoxication. At all serum concentrations of calcium, calcium clearance was lower in FHH than in controls; at base-line serum calcium, the ratio of calcium clearance to inulin clearance (C(Ca)/C(IN)) in FHH subjects was 32% of that in controls and decreased to 19% during hypercalcemia. Calcium infusion increased the ratio of sodium clearance to inulin clearance in controls from a base line of 0.020 to 0.053 at peak concentrations of calcium in serum, but did not affect this parameter in FHH (0.017 at base-line serum calcium vs. 0.019 at peak). When calcium infusion studies were performed (in two patients with FHH and one control) during administration of acetazolamide, a drug whose principal renal action causes inhibition of proximal transport of solute, C(Ca)/C(IN) in the patients with FHH was 29 and 7% of that of the control at base-line and peak serum calcium, respectively. In contrast, ethacrynic acid, a diuretic that acts in the ascending limb of the loop of Henle, increased C(Ca)/C(IN) more in the FHH patients than in the control subject; C(Ca)/C(IN) was 65% at base-line and 47% at peak serum calcium, compared with that of the control subject. The greater calciuric response to ethacrynic acid than to acetazolamide or calcium infusion alone in FHH indicates that a major renal locus of abnormal calcium transport in this disorder may be the ascending limb of the loop of Henle.Decreased clearance of calcium in patients with FHH and hypoparathyroidism when compared with hypoparathyroid controls indicates that relative hypocalciuria in FHH is not dependent on hyperparathyroidism. Since the parathyroid glands in FHH are not appropriately suppressed by calcium, this implies that FHH represents a disorder of abnormal transport of, and/or response to, extracellular calcium in at least two organs, parathyroid gland and kidney.

Impaired formation of beta-adrenergic receptor-nucleotide regulatory protein complexes in pseudohypoparathyroidism.

Decreased activity of the guanine nucleotide regulatory protein (N) of the adenylate cyclase system is present in cell membranes of some patients with pseudohypoparathyrodism (PHP-Ia) whereas others have normal activity of N (PHP-Ib). Low N activity in PHP-Ia results in a decrease in hormone (H)-stimulatable adenylate cyclase in various tissues, which might be due to decreased ability to form an agonist-specific high affinity complex composed of H, receptor (R), and N. To test this hypothesis, we compared beta-adrenergic agonist-specific binding properties in erythrocyte membranes from five patients with PHP-Ia (N = 45% of control), five patients with PHP-Ib (N = 97%), and five control subjects. Competition curves that were generated by increasing concentrations of the beta-agonist isoproterenol competing with [125I]pindolol were shallow (slope factors less than 1) and were computer fit to a two-state model with corresponding high and low affinity for the agonist. The agonist competition curves from the PHP-Ia patients were shifted significantly (P less than 0.02) to the right as a result of a significant (P less than 0.01) decrease in the percent of beta-adrenergic receptors in the high affinity state from 64 +/- 22% in PHP-Ib and 56 +/- 5% in controls to 10 +/- 8% in PHP-Ia. The agonist competition curves were computer fit to a "ternary complex" model for the two-step reaction: H + R + N in equilibrium HR + N in equilibrium HRN. The modeling was consistent with a 60% decrease in the functional concentration of N, and was in good agreement with the biochemically determined decrease in erythrocyte N protein activity. These in vitro findings in erythrocytes taken together with the recent observations that in vivo isoproterenol-stimulated adenylate cyclase activity is decreased in patients with PHP (Carlson, H. E., and A. S. Brickman, 1983, J. Clin. Endocrinol. Metab. 56:1323-1326) are consistent with the notion that N is a bifunctional protein interacting with both R and the adenylate cyclase. It may be that in patients with PHP-Ia a single molecular and genetic defect accounts for both decreased HRN formation and decreased adenylate cyclase activity, whereas in PHP-Ib the biochemical lesion(s) appear not to affect HRN complex formation.