Antipeptide antibodies against the 5-HT1A receptor.

The availability of the primary amino acid sequence for a large number of molecules provides a fruitful opportunity for their cellular localization by utilizing the procedure of antipeptide antibody formation. This procedure permits a synthetic peptide sequence to be attached to a carrier molecule for the purpose of inoculating an animal to raise specific antibodies against the selected protein sequence. In this report we describe a number of steps that can be taken to increase the likelihood that the selected peptide sequence will be specific and antigenic. In addition, we describe how the peptides are synthesized, purified and coupled to keyhold limpet hemocyanin. The preparation of the antibody and its characterization are also presented in this method report. The immunocytochemical staining at both the light and ultrastructural level with serotonin (5-HT1A) receptor antipeptide antibodies is discussed. The advantages and disadvantages of this procedure are summarized.     

Prenatal cocaine exposure disrupts the development of the serotonergic system.

Prenatal cocaine exposure has been found to result in a number of neurobehavioral abnormalities in both clinical and laboratory studies. We have previously shown that cocaine inhibits the growth of developing serotonin neurons in culture. This study examines the effects of cocaine on the developing serotonin system in vivo. Pregnant rats were injected with cocaine (40 mg/kg s.c.) from gestational day 13 to parturition. One group of rats was additionally injected on postnatal days 1-5 with cocaine (10 mg/kg s.c.). [3H]Paroxetine, a selective ligand for the serotonin uptake carrier, was used to quantify serotonin terminal fiber density at one day, one week, and four weeks postnatal. Cocaine exposure was found to significantly decrease [3H]paroxetine-labelled sites and thus the density of serotonin fibers in the cortex and hippocampus at one day and one week postnatal. By four weeks postnatal, no significant effect was observed, indicating that a recovery had occurred. Serotonin immunocytochemistry performed at one month revealed normal fiber distribution in the cortex but a loss of fibers in the CA1 and CA2 hippocampal fields. Postnatal treatment alleviated the effects of prenatal cocaine exposure, resulting in [3H]paroxetine binding levels at one week which were comparable to and, in the cortex, even higher than those of saline controls. We conclude that cocaine delays the maturation of the serotonin system when administered prenatally but may accelerate maturation when administered both pre- and postnatally.     

Glial fibrillary acidic protein immunoreactive astrocytes in developing rat hippocampus.

The developmental pattern of glial fibrillary acidic protein (GFAP)-immunoreactive astrocytes was investigated in the hippocampus (subfields CA1, CA3 and CA4) and in the dentate gyrus of male and female rats aged 11, 16, 30, 90 and 150 days by immunohistochemistry associated with image analysis. Analysis was centred on stratum radiatum, a hippocampal area rich in GFAP-immunoreactive astrocytes. The volume of different portions of hippocampus, the number and the size of astrocytes, the intensity of cell body GFAP immunostaining as well as the extension of astrocyte were assessed. A maturation pattern consisting in higher cellular expression of GFAP, an increase in overall cell size and expanding arborisation from the 11th to the 30th postnatal day, followed by stabilisation of these parameters until the 90th day of life, and a subsequent decrease in the oldest age group studied was found. A sex-related different temporal pattern of astrocytes maturation in size and GFAP content was observed in the CA1 subfield only. The increase of GFAP content during pre-weaning ages was less pronounced in females than in males as well as the decrease between the 90th and the 150th day of age. Moreover, the size of astrocytes was larger in females than in males at the 11th and 150th days of life. These findings suggest that hippocampal astrocytes undergo rapid maturation in the 1st month of postnatal life, followed by a slow consolidation of this process until the 3rd month of life. At 5 months of age, there are still dynamic changes in the mature astrocytes, which become slender and thinner probably as a response to the increased volume of hippocampus noticeable at this age.     

5-HT-immunoreactive fibers in the trigeminal nuclear complex of the rat

Summary The distribution of serotonin immunoreactive (5-HT-IR) fibers in the trigeminal nuclear complex of the rat was mapped. In the sensory nuclei, innervation appeared to be dense in areas primarily related to nociceptive afferent activity, and sparse in areas primarily related to nonnociceptive afferent activity. Specifically, the marginal and gelatinosa layers of the spinal subnucleus caudalis contained many 5-HT-IR fibers while few labeled fibers were seen in the magnocellular portion of subnucleus caudalis or in the principal sensory nucleus. The spinal subnuclei oralis and interpolaris were sparsely innervated except for a few areas which contained more 5-HT-IR fibers. The motor nucleus contained as many immunoreactive fibers as the subnucleus caudalis, although fibers in the motor nucleus were thicker and varicosities more irregularly spaced than in caudalis.This research was supported by grant BNS-79-06474 from the National Science Foundation awarded to Efrain Azmitia     

Evaluating Factors Contributing to Dropout in a Large Peritoneal Dialysis Program

BackgroundThe low prevalence of peritoneal dialysis (PD) (9%) vs. hemodialysis (HD) (88.2%) is partly due to patient dropout from therapy.MethodsThis retrospective study identified patients who withdrew from PD between 2016 and 2018 in our program. We evaluated all other factors as controllable losses. Analysis included time on therapy at dropout (very early, early or late) and method of initiation (HD to PD conversion, unplanned PD, or planned start).ResultsEighty-three patients enrolled into our PD program. 27 dropped out; 24 were due to controllable factors, 3 due to death, with a median age at dropout of 52 years old. We determined psychosocial factors (PF) to be the largest controllable factor influencing dropout; contributing a 63% rate among all controllable factors. When considering time until dropout, 100% of very early dropout patients and 50% of late dropout patients did so due to PF. Among early dropout patients 67% dropped out due to other medical reasons. The mean time to dropout for PF, other, and infection (INF) were 13, 26, and 33 months, respectively. When considering type of initiation, we found PF to be the largest attributable factor with 50% of unplanned, 100% of planned, and 50% of conversions stopping therapy.ConclusionsOur study indicates that the primary reason for controllable loss from therapy was secondary to PF regardless of the time on therapy or the method of initiation to therapy.     

Assessment and Management of Hypertension in Patients on Dialysis

Hypertension is common, difficult to diagnose, and poorly controlled among patients with ESRD. However, controversy surrounds the diagnosis and treatment of hypertension. Here, we describe the diagnosis, epidemiology, and management of hypertension in dialysis patients, and examine the data sparking debate over appropriate methods for diagnosing and treating hypertension. Furthermore, we consider the issues uniquely related to hypertension in pediatric dialysis patients. Future clinical trials designed to clarify the controversial results discussed here should lead to the implementation of diagnostic and therapeutic techniques that improve long-term cardiovascular outcomes in patients with ESRD.     

Antibody-mediated lymphocytotoxicity in rheumatoid arthritis and systemic lupus erythematosus

Lymphocyte-dependent antibody cytotoxicity (LDAC) was studied using peripheral blood and in some instances synovial fluid cells from patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). No difference from normal controls was observed with peripheral blood lymphocytes from either RA or SLE. Marked decrement in LDAC effector cell activity was present particularly with RA synovial fluid cells. Sera from patients with RA or SLE as well as RA synovial fluids markedly inhibited LDAC.