Pre-eclampsia is associated with sleep-disordered breathing and endothelial dysfunction.

Pre-eclamptic toxaemia (PET) may be associated with both endothelial dysfunction (ED) and sleep-disordered breathing (SDB). It was hypothesised that females with PET would demonstrate both SDB and ED, and that a correlation between these two would suggest a potential causative association. A total of 17 females with PET and 25 matched females with uncomplicated pregnancy were studied. They underwent a nocturnal ambulatory sleep study (using Watch_PAT100) and noninvasive evaluation of endothelial function utilising the reactive hyperaemia test (using Endo_PAT 2000). A higher ratio of post- to pre-occlusion pulse-wave amplitude (endothelial function index (EFI)) indicated better endothelial function. Females with PET had a significantly higher respiratory disturbance index (RDI) and lower EFI than controls (18.4+/-8.4 versus 8.3+/-1.3.h(-1), and 1.5+/-0.1 versus 1.8+/-0.1, respectively). Blood pressure significantly correlated with RDI and with EFI. EFI tended to correlate with RDI. In conclusion, these results suggest that both sleep-disordered breathing and endothelial dysfunction are more likely to occur in females with pre-eclamptic toxaemia than in females with uncomplicated pregnancies. The current authors speculate that respiratory disturbances contribute to the functional abnormality of the blood vessels seen in females with pre-eclamptic toxaemia, although causality cannot be determined based on this study.     

Isochronic transplantation of neonatal grafts in the visual cortex of cats: responsiveness,ocular dominance and specificity of cortical cells to visual stimulation

Summary The visual cortex of adult cats was studied physiologically following neonatal isochronic transplantation of grafts from areas 17,18, which were placed homotopically, in order to reveal their functional integration and thus possible repairing of damaged cortical neuronal circuits. Three homograft cats, in which transplantation was carried out between siblings (228 cortical cells) were compared to 4 animals receiving reimplanted autografts of the equivalent size (131 cells) as well as 3 animals with analogous sectioning of the visual cortex (162 cells) (pseudograft controls). The location of the boundaries between the transplant region and the host were determined using the Nissl's method for staining histological cross sections. Extracellular unit recording revealed typical waveform of the action potentials in the transplanted region and in the surrounding host tissue of all groups of cats. Visual responsiveness in the homograft cats was 17.5% in the transplanted region and 80.4% in the unoperated hemisphere; the corresponding results were 40.3% for the transplanted region and 82.2% for the unoperated hemisphere in the autografts and 23.1% and 73.4% in the pseudografts. The specificity of the cells to visual stimulation as expressed by their orientation and direction specificity, indicated preservation of these properties in the transplanted cats. While all responsive cells in the transplanted region of the homografts were orientation specific, their proportion was 60% in the autografts and 55.5% in the analogous region in the pseudograft controls. As to the direction specific cells, their performance in the grafted region of the grafted cats was even much higher than that of the pseudograft controls. The ocular dominance distribution of the cells showed preservation of binocularity in the transplanted region (90.0% binocular cells) of the homografts; it was however smaller in the equivalent region of the autografts (65.0%) and remarkably reduced (20.0%) in the pseudografts. It was concluded that despite the deafferentation induced during the transplantation procedure, a remarkable visual responsiveness was found in the transplanted region, indicating postoperative recovery. However, the cells there were mainly affected in their activity and less in their specificity to visual stimulation.     

Polymorphism of germ-line immunoglobulin VH genes correlates with allotype and idiotype markers

The polymorphic nature of the immunoglobulin V_H genes was investigated by Southern blot analysis of liver DNA of sixteen different mouse strains and hybridization with V_H probes. Differences in restriction enzyme pattern (REP) were observed and six different patterns of restriction fragments were found for the sixteen strains analyzed. No equivalent polymorphism was observed in another multigene family, the actins. The six patterns correlate with immunoglobin constant region allotypes (Igh-1). Experiments with Igh-1-congenic strains suggest that the V_H REP is linked to immunoglobulin constant region haplotype. Mouse strains which share inherited idiotypes also share identical V_H restriction pattern. This provides a structural basis for the genetic linkage between idiotypes and allotypes. It also indicates that different strains carry different VH gene repertoires, which may be the basis for the expression of different inherited idiotypes in various strains. We propose that a V_H group is a set of linked genes that are coinherited as a cluster with the constant region genes and that V_H and C_H can be regarded as an extended haplotype.     

Toxoplasma gondii: bystander or cofactor in rheumatoid arthritis

Parasitic infections may induce variable immunomodulatory effects and control of autoimmune disease. Toxoplasma gondii (T. gondii) is a ubiquitous intracellular protozoan that was recently associated with autoimmunity. This study was undertaken to investigate the seroprevalence and clinical correlation of anti-T. gondii antibodies in patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). We evaluated sera from European patients with RA (n = 125) and SLE (n = 164) for the prevalence of anti-T. gondii IgG antibodies (ATXAb), as well as other common infections such as Cytomegalovirus, Epstein-Barr, and Rubella virus. The rates of seropositivity were determined utilizing the LIAISON chemiluminescent immunoassays (DiaSorin, Italy). Our results showed a higher seroprevalence of ATXAb in RA patients, as compared with SLE patients [63 vs. 36 %, respectively (p = 0.01)]. The rates of seropositivity of IgG against other infectious agents were comparable between RA and SLE patients. ATXAb-seropositivity was associated with older age of RA patients, although it did not correlate with RA disease activity and other manifestations of the disease. In conclusion, our data suggest a possible link between exposure to T. gondii infection and RA.     

Fetal cardiomyopathy--in utero evaluation and clinical significance

OBJECTIVE: To describe the prenatal diagnosis and outcome of fetal cardiomyopathy (CM). METHODS: The charts, photographs and videotapes of all fetuses with CM, who were assessed during pregnancy at two referral centers, were reviewed. RESULTS: The diagnosis of CM was established in 12 fetuses. All had structurally normal hearts, and all cases were diagnosed after 23 weeks of gestation, following normal early fetal echocardiogram. Three clusters of fetal CM appeared: Familial--two sib fetuses of a mother, who is a second generation of CM. Both had dilated CM and pathological findings were consistent with the diagnosis of endocardial fibroelastosis. Secondary--CM that was induced by another factor. Idiopathic--six cases of CM without an underlying specific etiology. Three women elected to terminate their pregnancy. Among the nine who delivered, four had a favorable outcome with normal cardiac function at the age of 1 month, in which three belonged to the secondary category, and five cases were complicated by fetal/infant death. CONCLUSIONS: CM may develop during fetal life and might be diagnosed by prenatal echocardiography. Normal cardiac findings in a midtrimester fetus do not exclude subsequent development of CM. Detailed prenatal sonographic examination may aid in determining the neonatal outcome.     

Fetal pleural effusions

The clinical course of primary fetal hydrothorax is unpredictable. Whereas smaller unilateral effusions might remain stable or even regress, this is rarely the case with larger collections. Bilateral effusions, hydrops, preterm delivery and the lack of antenatal therapy are all associated with poor outcome. Once structural and chromosomal anomalies have been excluded, optimal management depends on gestational age, rate of progression, the development of hydrops and associated maternal symptoms. For very large effusions with mediastinal shift, hydrops and/or hydramnios, or when there is rapid enlargement of the effusion, fetal intervention is warranted. Survival can be maximized by pleuroamniotic shunting, which can reverse hydrops and hydramnios and prevent pulmonary hypoplasia. Pleuroamniotic shunting can also be used for the treatment of other large cystic lung lesions, such as a macrocystic congenital cystic adenomatoid malformation or bronchopulmonary sequestration, especially when associated with hydrops.     

Deprivation of pattern vision studied by visual evoked potentials in the rat cortex

In the present experiments we studied whether visual pattern deprivation affects the visual evoked potential (VEP) as has been assumed from modification of neuronal structures found in the rat cortex under this condition. The VEP of normal and of monocularly deprived rats is similar in waveform and composed of a small negative component at 40 msec, a large and fast positive wave (270 μV) with a latency of 67 msec and a negative afterpotential of 150 msec latency. The low ratio obtained in normal rats between the amplitudes of contralateral and ipsilateral VEPs (2.7:1) in comparison to the ratio of crossed and uncrossed fibers (15:1) indicates volume conduction interference with neural conduction. Mapping of the visual projection to the contralateral hemisphere in normal rats showed that area 17 was the visually most active region. Visual areas 18 and 18a were only secondary in their respnosiveness. Area 7, althought not considered to be a visual area, exhibited fair responses. The cortical region projected by the ipsilateral input overlapped the contralateral region. The mapping procedure was used to describe the responsiveness of monocularly deprived animals. Considering contralateral responses, area 17 of the normal hemisphere showed higher activity by 27% in comparison with the deprived hemisphere. Ipsilateral responses were similar in both cortices. The contralateral potentials recorded in control animals are higher in amplitude by 41% and their latencies are shorter than those recorded in the deprived animals contralaterally to the nondeprived eye. This may point to suppression of binocular interaction as a result of unilateral visual deprivation. It was concluded from the results in which animals were examined after deprivation of 70–170 days that specific neuronal changes occur due to visual deprivation and correlated with the suppression of the visual evoked potential. These changes differ from the gross processes characterized by neural degeneration since the visual system is still responsive.     

Effect of visual environment on refractive error of cats

33 eyes of 18 cats raised in cages or in small rooms under conditions of near vision were compared with 22 eyes of 11 street cats. Refraction of the caged cats showed that three quarters of them were myopic (average: ?0.8 D) while 87.5 percent of the street cats were hypermetropic (average: +1.4 D). The antero-posterior diameter was practically equal in both groups (20.4 mm) and in both myopic and hypermetropic eyes. The site of the permanent refractive changes is suggested to be the lens.