Differential actions of antiparkinson agents at multiple classes of monoaminergic receptor. III. Agonist and antagonist properties at serotonin, 5-HT(1) and 5-HT(2), receptor subtypes

Although certain antiparkinson agents interact with serotonin (5-HT) receptors, little information is available concerning functional actions. Herein, we characterized efficacies of apomorphine, bromocriptine, cabergoline, lisuride, piribedil, pergolide, roxindole, and terguride at human (h)5-HT(1A), h5-HT(1B), and h5-HT(1D) receptors [guanosine 5'-O-(3-[(35)S]thio)triphosphate ([(35)S]GTPgammaS) binding], and at h5-HT(2A), h5-HT(2B), and h5-HT(2C) receptors (depletion of membrane-bound [(3)H]phosphatydilinositol). All drugs stimulated h5-HT(1A) receptors with efficacies (compared with 5-HT, 100%) ranging from modest (apomorphine, 35%) to high (cabergoline, 93%). At h5-HT(1B) receptors, efficacies varied from mild (terguride, 37%) to marked (cabergoline, 102%) and potencies were modest (pEC(50) values of 5.8-7.6): h5-HT(1D) sites were activated with a similar range of efficacies and greater potency (7.1-8.5). Piribedil and apomorphine were inactive at h5-HT(1B) and h5-HT(1D) receptors. At h5-HT(2A) receptors, terguride, lisuride, bromocriptine, cabergoline, and pergolide displayed potent (7.6-8.8) agonist properties (49-103%), whereas apomorphine and roxindole were antagonists and piribedil was inactive. Only pergolide (113%/8.2) and cabergoline (123%/8.6) displayed pronounced agonist properties at h5-HT(2B) receptors. At 5-HT(2C) receptors, lisuride, bromocriptine, pergolide, and cabergoline were efficacious (75-96%) agonists, apomorphine and terguride were antagonists, and piribedil was inactive. MDL100,907 and SB242,084, selective antagonists at 5-HT(2A) and 5-HT(2C) receptors, respectively, abolished these actions of pergolide, cabergoline, and bromocriptine. In conclusion, antiparkinson agents display markedly different patterns of agonist and antagonist properties at multiple 5-HT receptor subtypes. Although all show modest (agonist) activity at 5-HT(1A) sites, their contrasting actions at 5-HT(2A) and 5-HT(2C) sites may be of particular significance to their functional profiles in vivo.     

Apoa5 Q139X truncation predisposes to late-onset hyperchylomicronemia due to lipoprotein lipase impairment

While type 1 hyperlipidemia is associated with lipoprotein lipase or apoCII deficiencies, the etiology of type 5 hyperlipidemia remains largely unknown. We explored a new candidate gene, APOA5, for possible causative mutations in a pedigree of late-onset, vertically transmitted hyperchylomicronemia. A heterozygous Q139X mutation in APOA5 was present in both the proband and his affected son but was absent in 200 controls. It was subsequently found in 2 of 140 cases of hyperchylomicronemia. Haplotype analysis suggested the new Q139X as a founder mutation. Family studies showed that 5 of 9 total Q139X carriers had hyperchylomicronemia, 1 patient being homozygote. Severe hypertriglyceridemia in 8 heterozygotes was strictly associated with the presence on the second allele of 1 of 2 previously described triglyceride-raising minor APOA5 haplotypes. Furthermore, ultracentrifugation fraction analysis indicated in carriers an altered association of Apoa5 truncated and WT proteins to lipoproteins, whereas in normal plasma, Apoa5 associated with VLDL and HDL/LDL fractions. APOB100 kinetic studies in 3 severely dyslipidemic patients with Q139X revealed a major impairment of VLDL catabolism. Lipoprotein lipase activity and mass were dramatically reduced in dyslipidemic carriers, leading to severe lipolysis defect. Our observations strongly support in humans a role for APOA5 in lipolysis regulation and in familial hyperchylomicronemia.     

Testis ultrasound in Klinefelter syndrome infertile men: making the diagnosis and avoiding inappropriate management

Objective

To compare the testicular Color Doppler ultrasound (US), hormone levels, and histological results from 67 infertile men with Klinefelter syndrome (KS), vs. 66 non-KS non-obstructive azoospermic men.

Methods

Scrotal US images were collected from 67 infertile KS and 66 non-obstructive, non-KS azoospermic men. The testis volume, echotexture, vascularity, and microliths were evaluated and graded. We defined the following echo pattern alteration groups: normal, striated, coarse, and measurable nodules. The vascularization was classified as low, normal, moderate, or strong. Testosterone, follicle-stimulating hormone, luteinizing hormone, and inhibin B levels were determined. Large testicular nodules were removed. A testicular biopsy and sperm extraction was performed in 18 of the KS, and all of the 66 non-KS men.

Results

The mean testis volume was low in the KS, compared to the non-KS patients: i.e., 2 vs. 8 mL (P < 0.0001). The distributions in the echotexture groups differed markedly, with coarse or nodular patterns in the KS men, and normal/striated patterns in the control patients (P < 0.0001). The vascularization and microlithiasis grades were higher in the KS patients than the control men (P < 0.0001 and P < 0.001, respectively). All of the nodules removed from the KS patients were benign Leydig cell tumors, and all of the biopsies showed marked Leydig cell hyperplasia, with spermatogenesis in only two patients. The non-KS biopsies were predominantly Sertoli cell-only syndrome.

Conclusions

Small testes, with a coarse or nodular echotexture, hypervascularization, and microlithiasis are associated with KS. The KS nodules were benign Leydig cell tumors/hyperplasias.

     

Kangaroo supported diagonal flexion positioning: Positive impact on maternal stress and postpartum depression risk and on skin-to-skin practice with very preterm infants

Purpose

To test the effects of a new skin-to-skin Supported Diagonal Flexion (SDF) positioning on maternal stress, postpartum depression risk and skin-to-skin daily practice, in comparison with the usual Kangaroo Care in Upright positioning, during the first weeks after very premature birth.

Clinical and immunological effects of a 6 week immunotherapy cycle with murabutide in HIV-1 patients with unsuccessful long-term antiretroviral treatment

In an effort to evaluate the potential of non-specific immunotherapy in restoring global immunity, we have examined the clinical tolerance and biological effects of a 6 week administration of the immunomodulator, murabutide, in chronically infected HIV-1 patients. Forty-two subjects, presenting weak immune reconstitution and ineffective virus suppression following long-term highly active antiretroviral therapy (HAART), were randomized to receive, or not, murabutide 7 mg/day on five consecutive days/week. Clinical and immunological parameters were monitored before and after the immunotherapy period. Administration of murabutide was generally well tolerated, although some grade III adverse events, reversible on treatment cessation, were observed. Interestingly, in comparison with pre-inclusion levels, at 1 week after the immunotherapy cycle, only murabutide recipients presented a significant increase in CD4 cells, platelet counts, and in the percentage of patients with undetectable viral loads (<50 copies/mL). Statistical significance between the two groups was only evident with the latter parameter. Some of these clinical changes were maintained even up to 12 weeks after murabutide administration, and were accompanied by an increased ability to mount cellular responses to active immunization with a recall antigen, and by a significant increase in the percentage of patients presenting positive lymphoproliferative responses to the viral antigen gp160. These results warrant further evaluation of extended periods or cycles of murabutide immunotherapy as adjunct to HAART.     

Prospective observational study of drug-induced hyperkalemia in hospitalized non dialized adult patients

OBJECTIVE: To study the incidence and risk factors of drug-induced hyperkalemia in adult, hospitalized patients. METHODOLOGY: A three months prospective observational study was used including all hospitalized, non dialyzed, patients older than 17 years who presented with a hyperkalemia egal or over 6 mmol/L. The studied variables were demographic, clinical, biological and therapeutic. RESULTS: Forty patients, among 112 included, had a hyperkalemia promoted by drug(s) (3.5 cases for 1000 hospitalized patients). They were 73 +/- 15 years old and 72.5% had a past medical history of chronic renal failure. The hyperkalemia (6.42 +/- 0.48 mmol/L) was associated with an increase in creatininemia in 67.5% of patients. The most frequent treatment observed were renin angiotensin system drugs in 62.5% of patients, spironolactone in 37.5% or both drugs in 25%. CONCLUSION: A better use of these drugs would be able to prevent some cases of hyperkalemia.     

Effect of Intraluminal Flow on Proximal Tubular Reabsorption

Micropuncture techniques in the rat were used to reinvestigate the possibility that intraluminal flow rate per se may influence net volume reabsorption by the proximal tubule. An experimental design was devised which lowered intraluminal flow without affecting filtration rate of the nephron under study or without directly affecting other renal hemodynamics. In 11 rats flow of tubular fluid between early and late proximal tubular sites was reduced by partially collecting tubular fluid at the early puncture site. In 42 nephrons the rate of flow of tubular fluid was reduced an average of 45% without changing nephron filtration rate and there was an associated reduction in reabsorption between the two sites which averaged 29%. This indicated 63% balance between delivery of tubular fluid and the rate of reabsorption between two sites along proximal tubules. The results of these studies indicate that a reduction in delivery of normal filtrate along the proximal tubule is associated with a concordant reduction in the absolute rate of reabsorption. Since this relationship occurred in the absence of changes in renal hemodynamics or even a change in filtration rate of the nephron under study it is concluded that changes in intraluminal load per se play an important role in the phenomenon of glomerulotubular balance.     

Moving Beyond Content Validation of Nursing Diagnoses

TOPIC. Studies to establish construct and criterion-related validity of nursing diagnoses.
PURPOSE. The overwhelming majority of previous studies addressed content validation by nurse experts. This paper describes strategies to move beyond content validation research to construct and criterion-related validation.
SOURCES. The range of studies that should be conducted for development of nursing diagnoses are reviewed with examples drawn from the field of psychology. Existing studies on the diagnoses of ineffective breathing pattern, ineffective airway clearance and impaired gas exchange are used as examples.
CONCLUSIONS. Many types of studies are needed for each nursing diagnosis. Increased funding and support for nursing diagnosis research will be facilitated by attention to the accuracy of nurses' diagnoses and outcomes of the diagnostic process.     

Somatic non-cancerous overgrowth syndrome of obscure molecular etiology: what are the causes and options?

Journal of Molecular Medicine -