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PubMed1992

Reappraisal of the coupling interval of ventricular extrasystoles as an index of ectopic mechanisms.

OBJECTIVE: A mathematical model of modulated ventricular parasystole based on the relation between the coupling interval and the preceding RR interval was developed in an attempt to distinguish between parasystolic automaticity and other mechanisms. MATHEMATICAL MODEL: The relation between the coupling interval and the preceding RR interval was examined by plotting the coupling interval of each extrasystole against the preceding RR interval (coupling interval/RR diagram). The coupling interval/RR diagrams obtained from simulations with various modulation modes suggested that the parasystolic mechanism was likely when the dots representing extrasystoles appeared as discrete clusters. In contrast, a linear horizontal accumulation of dots indicated a non-parasystolic mechanism. CLINICAL OBSERVATION: To verify the validity of the simulations, 24 hour electrocardiographic recordings from 60 patients with frequent ventricular extrasystoles (> 1000/day) were analysed to determine whether the extrasystoles showed intrinsic periodicity. Intrinsic periodicity indicative of a parasystolic mechanism was seen in 14 (93%) of 15 patients in whom the coupling interval/RR diagram was characteristic of a parasystolic mechanism. When the coupling interval did not change (variability < 200 ms) over a wide range of RR intervals (> 700 ms) intrinsic periodicity was never identified (0/17). Parasystolic automaticity was the likely mechanism in 11 of the remaining 28 patients (39.3%) in whom coupling interval/RR diagrams were not definitive. CONCLUSION: These data indicate that definite patterns of coupling interval/RR diagrams can be used to distinguish between parasystolic and non-parasystolic mechanisms.

Adolescent↗

PubMed1997

Functional coupling in bovine ciliary epithelial cells is modulated by carbachol.

The functional coupling of the ciliary epithelium was studied in isolated pairs (couplets) of pigmented ciliary epithelial (PCE) and nonpigmented ciliary epithelial (NPCE) cells using the whole cell patch clamp and the fluorescent dye lucifer yellow. One cell of the pair (usually the NPCE cell of a NPCE-PCE cell couplet) was accessed with a 2-5 M omega electrode, containing 1-2 mM lucifer yellow, in the whole cell configuration of the patch clamp. After voltage-clamp experiments were completed, cells were viewed under a fluorescent microscope to confirm that the cells were coupled. The electrical coupling of the cells was also studied by calculating the capacitance (using the time-domain technique), assuming a "supercell" model for coupled cells. The mean capacitance of coupled pairs was 79.8 +/- 4.3 (SE) pF (n = 47) compared with single cell capacitances of 36.8 +/- 3.4 pF (n = 10) for PCE cells and 38.1 +/- 3.1 pF (n = 15) for NPCE cells. Octanol, carbachol (CCh), and raised extracellular Ca2+ concentration ([Ca2+]o) all caused uncoupling in pairs (couplets) of coupled NPCE and PCE cells. At room temperature (22-24 degrees C), the capacitance of the couplets decreased from 70.5 +/- 8.0 to 48.0 +/- 5.2 pF (n = 5) when exposed to octanol (1 mM), from 73.8 +/- 9.2 to 43.2 +/- 9.5 pF (n = 4) when exposed to CCh (100 microM), and from 80.5 +/- 6.7 to 49.9 +/- 7.8 pF (n = 4) when exposed to 10 mM [Ca2+]o. The response to CCh was dose dependent; at higher temperatures of 34-37 degrees C, 10 microM CCh caused a 38% reduction in capacitance, from 53.7 +/- 9.7 to 33.5 +/- 3.3 pF (n = 7) with a half-time of 249 s, and 100 microM CCh caused a 49% reduction in capacitance, from 51.3 +/- 5.6 to 26.0 +/- 2.4 pF (n = 7) with a half-time of 124 s. After pairs uncoupled and the uncoupling agent was washed out, the cell pairs often exhibited an increase in capacitance that we interpreted as "recoupling" or a reopening of the gap junctional communication pathway; the half-time for this process was 729 s after uncoupling with 100 microM CCh and 211 s after uncoupling with 10 microM CCh. This interpretation was confirmed optically by the spread of lucifer yellow into both cells of an uncoupled pair with a time course corresponding to the increase in electrical coupling. The controllable coupling of ciliary epithelial cells extends the idea of a functional syncytium involved in active transport. PCE cells take up solute and water from the blood, which then cross to NPCE cells via gap junctions and from there are secreted into the posterior chamber of the eye. Modulation of the coupling between NPCE and PCE cells may provide a mechanism to control secretion.

Animals↗

PubMed2006

Differential coupling of beta3A- and beta3B-adrenergic receptors to endogenous and chimeric Galphas and Galphai.

Chimeric G proteins made by replacing the COOH-terminal heptapeptide of G(alpha)q with the COOH-terminal heptapeptide of G(alpha)s or G(alpha)i were used to assess the relative coupling of beta(3)-adrenergic receptor (beta(3)-AR) splice variants (beta(3A) and beta(3B)) to G(alpha)s and G(alpha)i. The G(alpha)q/s and G(alpha)q/i chimeras transformed the response to receptor activation from regulation of adenylyl cyclase to mobilization of intracellular calcium (Ca(2+)(i)). Complementary high-throughput and single-cell approaches were used to evaluate agonist-induced coupling of the receptor to the G protein chimeras. In cells stably transformed with rat beta(3)-AR, transfected with the G protein chimeras, and evaluated using a scanning fluorometer, beta(3)-AR-induced coupling to G(alpha)q/s produced a rapid eightfold increase in Ca(2+)(i) followed by a slow decay to levels 25% above baseline. G(alpha)q/i also linked rat beta(3)-AR to mobilization of Ca(2+)(i) in a similar time- and agonist-dependent manner, but the net 2.5-fold increase in Ca(2+)(i) was only 30% of the response obtained with G(alpha)q/s. Activation of the rat beta(3)-AR also increased GTP binding to endogenous G(alpha)i threefold in membranes from CHO cells stably transformed with the receptor. A complementary single-cell imaging approach was used to assess the relative coupling of mouse beta(3A)- and beta(3B)-AR to G(alpha)i under conditions established to produce equivalent agonist-dependent coupling of the receptor splice variants to G(alpha)q/s and to increases in intracellular cAMP through endogenous G(alpha)s. The beta(3A)- and beta(3B)-AR coupled equivalently to G(alpha)q/i, but the temporal patterns of Ca(2+)(i) mobilization indicated that coupling was significantly less efficient than coupling to G(alpha)q/s. Collectively, these findings indicate less efficient but equivalent coupling of beta(3A)- and beta(3B)-AR to G(alpha)i vs. G(alpha)s and suggest that differential expression of the splice variants would not produce local differences in signaling networks linked to beta(3)-AR activation.

Adenylyl Cyclases↗

PubMed2005

Effect of electrical coupling on ionic current and synaptic potential measurements.

Recent studies have found electrical coupling to be more ubiquitous than previously thought, and coupling through gap junctions is known to play a crucial role in neuronal function and network output. In particular, current spread through gap junctions may affect the activation of voltage-dependent conductances as well as chemical synaptic release. Using voltage-clamp recordings of two strongly electrically coupled neurons of the lobster stomatogastric ganglion and conductance-based models of these neurons, we identified effects of electrical coupling on the measurement of leak and voltage-gated outward currents, as well as synaptic potentials. Experimental measurements showed that both leak and voltage-gated outward currents are recruited by gap junctions from neurons coupled to the clamped cell. Nevertheless, in spite of the strong coupling between these neurons, the errors made in estimating voltage-gated conductance parameters were relatively minor (<10%). Thus in many cases isolation of coupled neurons may not be required if a small degree of measurement error of the voltage-gated currents or the synaptic potentials is acceptable. Modeling results show, however, that such errors may be as high as 20% if the gap-junction position is near the recording site or as high as 90% when measuring smaller voltage-gated ionic currents. Paradoxically, improved space clamp increases the errors arising from electrical coupling because voltage control across gap junctions is poor for even the highest realistic coupling conductances. Furthermore, the common procedure of leak subtraction can add an extra error to the conductance measurement, the sign of which depends on the maximal conductance.

Analysis of Variance↗

PubMed1978

Fixed coupling: different mechanisms revealed by exercise-induced changes in cycle length.

Fixed coupled ventricular premature depolarizations (VPDs) are usually considered reentrant; recent experimental models have demonstrated that parasystolic rhythms may also appear in fixed coupled patterns. To analyze the mechanisms of fixed coupled VPDs, 60 exercise tests were chosen to evaluate the response of VPD coupling intervals to changes in cycle length of the dominant supraventricular rhythm. Selection criteria included the presence of frequent, unifocal VPDs that were fixed coupled (variation less than or equal to 80 msec) at any one cycle length, with the persistence of VPDs at several different cycle lengths. Three patterns of response of coupling intervals to changes in cycle length were noted: 1) 32 patients with a direct linear relation (r greater than or equal to 0.9) of coupling intervals to cycle length; 2) 16 patients with coupling intervals fixed, independent of cycle length; and 3) 12 patients with no consistent relation over a wide range of cycle lengths. Two patients in group 2 and four in group 3 fulfilled criteria for parasystole with interectopic intervals that remained constant at different cycle lengths. These results suggest that VPDs in group 1 are reentrant, while some patients with group 2 or 3 responses have evidence for parasystolic rhythms. We conclude that 1) fixed coupling of VPDs is not diagnostic of reentry, and 2) changes in cycle length induced with exercise may be useful in the analysis of mechanisms of VPDs.

Adolescent↗

PubMed2006

Couples surviving prostate cancer: Long-term intimacy needs and concerns following treatment.

Couples surviving prostate cancer face long-term challenges in their relationships as they adapt to chronic illness. Ten couples surviving prostate cancer were brought together in a focus group to discuss their experiences and concerns regarding intimacy in their relationships. During three 30-minute segments, couples described their experiences (a) as couples, (b) as individual men and women in two concurrent break-out groups, and (c) regarding current intimacy and relationship needs. Questions asked of couples focused on (a) the process of being diagnosed and treated for prostate cancer, (b) what the experience was like for them as a couple, (c) what was helpful, harmful, and surprising throughout the experience, (d) what they currently needed most as a couple, and (e) what advice they had for other couples. Findings suggested that men and women think and respond differently to intimacy and relationship challenges that occur as a result of prostate cancer, diagnosis, and treatment. Consequently, healthcare providers in any clinical setting who may interact with prostate cancer survivors must consider the relationship and intimacy needs that are unique to men, women, and couples.

Adaptation, Psychological↗

PubMed1986

Evidence, by in vitro enzymatic iodination of thyroglobulin, that the efficiency of coupling is determined by the initial iodide concentration.

The rate of iodination and the extent and the efficiency of coupling, assessed by the T4 residues formed per atom of iodine bound, have been studied by in vitro enzymatic iodination of iodine-poor (0.01% I) human goiter thyroglobulin (Tgb; 1 microM) with varying concentrations of iodide (0.75 X 10(-5)-10(-4) M I-), lactoperoxidase (0.1-5 micrograms/ml), and hydrogen peroxide (H2O2) generated from glucose (1 mg/ml) and glucose oxidase (0.025-2.5 mU/ml). Under the experimental conditions used, variations in the H2O2 concentration affect the rate of iodination, but not the extent of coupling. Variations in the peroxidase concentration do not affect the rate of iodination or the coupling efficiency. Variations in the iodide concentration do not affect the rate of iodination, but do affect the coupling efficiency, which is higher the lower the initial iodide concentration. Both iodination and coupling take place almost simultaneously. They are catalyzed by peroxidase, and iodination is completed earlier the lower the iodide concentration. Therefore, once iodination is complete, coupling alone, with high efficiency, takes place. This suggests that the active peroxidase compounds formed will be mainly directed toward the catalysis of iodination or coupling, depending on the actual iodide concentration present in the incubation medium. Provided that initially nonlimiting noninhibiting H2O2 and iodide concentrations are used and that iodination and coupling are allowed to proceed to completion, the extent of coupling is a function of the degree of iodination of Tgb achieved, and its efficiency is determined not just by the native structure of Tgb, but also by the initial iodide concentration used.

Goiter, Nodular↗

PubMed1995

Wing-beat coupling between flying locust pairs: preferred phase and lift enhancement

Pairs of locusts flying in tandem in a wind tunnel are known to couple their wing-beats intermittently. The rhythmically oscillating air flow from the front locust's wing-beat, detected by the rear individual, appears to convey the timing information for coupling. Three predictions of this arrangement were tested quantitatively in this study. (1) Given that the oscillating air flow has a wavelength of 7.5 cm, placing the rear locust 7.5 or 15 cm behind the front one should produce the same phase of coupling, whereas placing it at an intermediate distance of 11 cm should produce an opposite phase. (2) At any distance, the preferred phase at which wing-beat coupling occurs should depend, in part, on the difference in the wing-beat frequencies of the two locusts just before the coupling began. (3) At the moment that the wing-beats of the two locusts become coupled, a change should be observed consistently in the wing-beat frequency of the rear individual only. Each of these three predictions was fulfilled. We also recorded the instantaneous lift of the rear locust by tethering it to a laser torque meter. Lift varied with the phase of the wing-beats between the two locusts. For a given distance between the two locusts, lift was greater by a mean of 16 % of the locust's body mass at those phases where coupling most commonly occurred than at opposite phases. This lift effect was seen even if the wing-beats of the two locusts drifted through these preferred phases without actually coupling. These results are discussed in terms of a possible energetic advantage conferred to the rear locust by flying in tandem and by coupling its flight rhythm to the leader's wing-beat.

Journal Article↗

PubMed2006

Highly efficient optical coupling and transport phenomena in chains of dielectric microspheres.

Using the generalized multiparticle Mie theory, we investigate optical coupling and transport through chains of dielectric microspheres. We identify two distinct coupling mechanisms of optical transport in terms of the coupling efficiency between neighboring microspheres, namely, evanescent coupling and nanojet coupling. We demonstrate that perfect whispering gallery mode propagation through a chain of evanescently coupled microspheres can be achieved. However, optical coupling and transport through a chain of nanojet-inducing microspheres is less efficient due to the radiative nature of photonic nanojets. Understanding these two optical coupling mechanisms is critical for selecting appropriate microspheres to build coupled resonator optical waveguides and other photon-manipulation devices for effective and low-loss guiding of photons.

Journal Article↗

PubMed2004

Effect of lung volume reduction surgery on diaphragmatic neuromechanical coupling at 2 years.

STUDY OBJECTIVES: We previously reported that patients with emphysema show an increase in diaphragmatic neuromechanical coupling at 3 months after lung volume reduction surgery. Diaphragmatic neuromechanical coupling was quantified as the quotient of tidal volume (normalized to total lung capacity) to tidal change in transdiaphragmatic pressure (normalized to maximal transdiaphragmatic pressure). As such, neuromechanical coupling estimates the fraction of diaphragmatic capacity used to generate tidal breathing. The present investigation was conducted to determine whether benefit is maintained at 2 years. SUBJECTS: Fifteen patients with severe COPD, 8 of whom completed the 2-year study. METHODS: Lung volumes, exercise capacity (6-min walking distance), diaphragmatic function (maximal transdiaphragmatic pressure and twitch transdiaphragmatic pressure elicited by phrenic nerve stimulation), and diaphragmatic neuromechanical coupling were recorded before surgery, and at 3 months and 2 years after surgery. RESULTS: Two years after surgery, lung volumes deteriorated to preoperative values, but patients showed persistent improvements in 6-min walking distance (p < 0.05). Three months after surgery, maximal transdiaphragmatic pressure (p < 0.05), twitch transdiaphragmatic pressure (p < 0.01), and diaphragmatic neuromechanical coupling (p < 0.01) had increased over preoperative values. The improvements in neuromechanical coupling resulted from improvements in diaphragmatic strength and, to a lesser extent, from a decrease in transdiaphragmatic pressure required to maintain tidal breathing. The change in respiratory muscle function at 2 years varied among patients: diaphragmatic contractility was > 10% of preoperative value in half of the patients who concluded our study, and neuromechanical coupling was > 10% of preoperative value in three fourths of the patients who concluded our study. Patients who maintained their gains in neuromechanical coupling also maintained their gains in 6-min walking distance. CONCLUSION: Patients undergoing lung volume reduction surgery can maintain early gains in neuromechanical coupling and exercise capacity 2 years later.

Aged↗

PubMed2002

Comparison of the function of exchange in couples of similar and differing physical attractiveness.

Couples (22 young, married, 18 young unmarried) completed the Exchange Orientation Scale, which measures how much individuals believe equality of exchange should characterize their social relationships, as well as the Norman Personality Trait Scale, which gives measures for the self and ideal-self. Couples also rated their sexual satisfaction, their partners' physical attractiveness, their own attractiveness, and had their photographs evaluated for attractiveness by disinterested raters. Subgroups were formed of physically attractive couples, couples in which the members were of disparate attractiveness, and couples in which the individuals perceived themselves as equal to their partners in attractiveness or as inferior. In accordance with exchange theory, the hypotheses were (1) unmarried men would show higher exchange scores than married men, (2) attractive men in disparately attractive couples would show greater exchange scores than attractive men in both-attractive couples, (3) attractive members of disparately attractive couples would possess lower self-acceptance and (4) experience greater sexual satisfaction than attractive members of both-attractive couples. Results supported all hypotheses in varying extents.

Adult↗

PubMed1999

Nitric oxide via cGMP-dependent mechanisms increases dye coupling and excitability of rat supraoptic nucleus neurons.

Unlike many neuron populations, supraoptic nucleus (SON) neurons are rich in both nitric oxide synthase (NOS) and the NO receptor-soluble guanylyl cyclase (GC), the activation of which leads to cGMP accumulation. Elevations in cGMP result in increased coupling among SON neurons. We investigated the effect of NO on dye coupling in SONs from male, proestrus virgin female, and lactating rats. In 167 slices 263 SON neurons were recorded; 210 of these neurons were injected intracellularly (one neuron per SON) with Lucifer yellow (LY). The typically minimal coupling seen in virgin females was increased nearly fourfold by the NO precursor, L-arginine, or the NO donor, sodium nitroprusside (SNP). L-Arginine-induced coupling was abolished by a NOS inhibitor. In slices from male and lactating rats who have a higher basal incidence of coupling, SNP increased coupling by approximately twofold over control (p < 0.03). SNP effects were prevented by the NO scavenger hemoglobin (20 microM) and by the selective blocker of NO-activated GC, ODQ (10 microM). These results suggest that NO released from cells within the SON can expand the coupled network of neurons and that this action occurs via cGMP-dependent processes. Because increased coupling is associated with elevated SON neuronal excitability, we also studied the effects of 8-bromo-cGMP on excitability. In both phasically and continuously firing neurons 8-bromo-cGMP (1-2 mM), but not cGMP, produced membrane depolarizations accompanied by membrane conductance increases. Conductance increases remained when depolarizations were eliminated by current-clamping the membrane potential. Thus, NO-induced cGMP increases SON neuronal coupling and excitability.

Animals↗

PubMed1980

[Kyodo: Guizhou couple 'punished' for having third child].

A Chinese couple in Guizhou Province have been subjected to severe disciplinary steps for having a 3rd child in defiance of the state guideline for controlling population growth. According to the Guizhou Daily, reaching Beijing Sunday, the wife, Wen Jifang, who had been deputy chief of a county people's court in the province, was stripped of the court post as a disciplinary measure. The husband, Lu Yutang, deputy chief of the public prosecutor's office in the same county, was ordered to receive sterilization surgery. In addition to the punishment, the county Communist Party committee harshly reprimanded the couple for having ignored the party's urging that an abortion be carried out, the paper siad. Both the husband and wife had their salaries cut, it said. The couple had 2 girls before the wife gave birth to a son last November despite the local party leadership's repeated persuasion for an abortion, the local paper said. The couple had the strong hope to have a boy, it said. The paper blasted the couple for failing to discard the "old thinking" setting a higher value on males. The local authorities' action against the couple received strong support among the general public in the province, the paper said. China is imposing strict control on population growth with the goal of zero growth by the end of this century. It failed to achieve last year's target which was a growth rate of less than 1%. China set a severe goal this year of allowing only 1 child for 95% of the total couples living in urban areas and for 90% of the couples in provincial areas. Couples who are Communist Party members are liable to harsher disciplinary action in case of "excessive" childbirth.

Asia↗

PubMed2006

Epidemiology of depression among infertile and fertile couples in Shiraz, southern Iran.

BACKGROUND: Depression is considered as one of the main psychological disorders associated with infertility. Depression may play a significant role in the life of infertile individuals, their infertility treatment follow-up and in their hopefulness for the future; it may also influence the intensity and continuousness of the mutual relationship of the affected couple. AIMS: This study was done to determine the depression rate and make a comparison between infertile and fertile couples with respect to the same. SETTING AND DESIGN: The depression rate was evaluated between two groups--infertile couples (case group) and fertile couples (control group). MATERIALS AND METHODS: Ninety-one infertile couples (cases) and 9l fertile ones (controls) were randomly enrolled in our study. Beck depression inventory (BDI) and demographic information were provided. STATISTICAL ANALYSIS: We used Chi-square, t-test; and one-way Analysis of Variance (ANOVA) was performed to find out significant difference between infertility duration in various couples and its effect on the score of depression. RESULTS: The BDI mean difference between infertile and fertile couples was significant (P=0.015). It was significantly more among couples with infertility from 1-3 years' duration compared to those with infertility of 1-year duration or less. CONCLUSION: Regarding the high rate of depression among infertile couples, it seems necessary to pay more attention to infertility centers that offer psychological and psychiatric services.

Adult↗

PubMed1992

Decreased fecundability in Hutterite couples sharing HLA-DR.

To study the effects of parental HLA sharing on pregnancy outcome, we initiated population-based studies in the Hutterites. We previously reported longer intervals from marriage to each birth among couples sharing HLA, particularly HLA-DR. In the present report, we present the results of a prospective, 5-year study of fecundability and fetal loss rates in this population. Between April 1986 and April 1991, 154 pregnancies were observed in 104 couples. The median number of months of unprotected intercourse to a positive pregnancy test was significantly longer among couples sharing HLA-DR who stopped nursing prior to the first menses as compared with couples not sharing HLA-DR who stopped nursing prior to the first menses (5.1 vs. 2.0 mo, respectively; P = .016). Fetal loss rates were increased among couples sharing HLA-B as compared with couples not sharing HLA-B (.23 vs. .12, respectively; P = .041, adjusted for age, gravidity, and kinship). These data suggest that our earlier observations of increased birth interval lengths among Hutterite couples sharing HLA were predominantly due to longer intervals until a clinical pregnancy among couples sharing HLA-DR and, to a lesser degree, were due to increased fetal loss rates among couples sharing HLA-B.

Abortion, Spontaneous↗

PubMed1980

[Crisis-phenomena of couples in the second half of life (author's transl)].

In the introduction a literature-review has been presented concerning current discussions about marriage problems and their influence on the duration of marriage. It has been shown that a clear differentiation between disturbed and non-disturbed couples in the second half of life is as difficult as a differentiation between disturbed couples of different age. Both problems were discussed in the present investigation. For this purpose a symptom-check-list of martial diseases has been developed on a psychometric basis measuring 16 groups of martial diseases. This symptom-check-list was applied to 115 couples (non-disturbed and disturbed couples in the second half of life and disturbed couples in the first half of life). The individual answers were combined to dyadic answers; the mean-profiles of the three groups were summarized in one figure and were statistically analysed using a discriminance-analysis. In comparison to nondisturbed couples disturbed couples in the second half of life show a deficit of appreciation and of talking to each other and also differ with respect to their aims or expectations towards marriage. In comparison to couples in the first half of life disturbed couples in the second half of life have more problems concerning appreciation and the relation to their children. But they have comparatively less problems in the relation to their parents or relatives and in their professions. The results were discussed under the aspect of a clinical psychology of the second half of life and were discussed under the aspect of the possibility of their theoretical integration.

Aged↗

PubMed1983

Coupling between neurons of the developing rat neocortex.

We have estimated the prevalence of coupling between neurons of the rat neocortex during postnatal development. Single intracellular injections of the fluorescent dye Lucifer Yellow CH resulted in dye coupling among 70% of neurons from 1 to 4 days of age. Dye coupling dropped to 30 to 40% by 10 to 18 days and occurred in 20% of injected adult neurons. The number of neurons per dye-coupled aggregate also decreased. Whereas three to seven coupled neurons were common in cortex of 1 to 4 days, aggregates of more than two neurons were exceptionally rare in adults. The frequency of dye coupling did not vary systematically with cortical depth at any age. When chemical synaptic activity was blocked, most 4-day neurons exhibited short latency antidromically evoked depolarizations which were relatively insensitive to repetitive activation and membrane polarization. These depolarizations may represent electrotonically conducted spikes from coupled neurons. No such potentials were found in adult neurons. The results suggest that neuronal coupling is extensive in immature rat neocortex, but that coupling declines at a time just before the numbers of chemical synapses increase most rapidly.

Aging↗

PubMed1982

HLA-DR compatibility in couples with recurrent spontaneous abortions.

HLA antigens and antibodies of A,B and DR loci were investigated in order to study the relationship between early recurrent spontaneous abortions of unknown etiology and the HLA system, which is in a close relationship with the immune response. The frequencies of 8 HLA-A antigens, 21 HLA-B antigens and 10 HLA-DR antigens were determined in 26 patient couples, 45 control fertile couples without a history of abortion and 206 healthy adult controls (DR antigens in 106 controls). Sera from the wives in patient couples were tested for HLA-A, B, C and DR antibodies against their husbands' T and B lymphocytes and also against 2 panels of 29 typed T and B lymphocytes. Results obtained were as follows: 1) A significantly higher frequency of HLA-All antigen was found in the wives in patient couples as compared with the controls (corrected p less than 0.008). 2) A significantly higher frequency of one or two common HLA-DR antigens was shared by patient couples (84.6%, X2 = 21.66, p less than 0.001) as compared with control couples (24.4%). 3) Furthermore, a significantly higher frequency about HLA-DR locus without major incompatibility was found in patient couples (26.9%, X2 = 7.77, p less than 0.01) as compared with control couples (2.2%). 4) HLA-DR antibodies were not detected in the wives in patient couples at all. These results indicated that the compatibility of HLA-DR antigens or DR genes might possess some adverse influence on the maintenance of pregnancy.

Abortion, Habitual↗