Expression of laminin and nidogen genes during the postimplantation development of the mouse placenta

The expression patterns of laminin A, B1, B2, and nidogen genes were identified by in situ hybridization in postimplantation mouse extraembryonic tissues and maternal decidua during the period when the chorioallantoic placenta is established. Laminin and nidogen genes were not coordinately expressed either in the decidua or in trophoblast cells, indicating that these genes are regulated independently in these cell types during the establishment of the placenta. Laminin A mRNA was absent from the decidua except in the outer layer of cells adjacent to the myometrium and in the central decidual zone adjacent to the remnant of the uterine epithelium on Day 9. At this stage laminin B1, B2, and nidogen genes were strongly expressed in these cells and also in other regions of the decidua. Laminin B1 mRNA was present at higher levels in the decidua capsularis than in the decidua basalis, while nidogen mRNA showed highest expression in the decidua basalis. Laminin B2 mRNA was produced uniformly throughout the decidua at very high levels, suggesting that laminin B2 chains may be an important component of the decidual matrix. By Day 11, the nidogen gene was expressed only in endothelial cells lining the maternal blood spaces within the decidua. Laminin B1 and nidogen mRNAs were found at high levels within trophoblast giant cells at all stages, while laminin A mRNA was detected in trophoblast giant cells at later stages and laminin B2 mRNA was not produced in high levels by these cells. The patterns of gene expression show a very high degree of regional specialization, suggesting that the extracellular matrices in different regions of the decidua and extraembryonic membranes are likely to be composed of quite different ratios of laminin and nidogen polypeptides.(ABSTRACT TRUNCATED AT 250 WORDS)     

Ultrastructural study of the early development of the sheep embryo

An ultrastructural study of the different stages of pre-implantation in sheep was carried out, analysing the changes brought about mainly in the morula and blastocyst stages. The analysis of the embryos obtained showed a series of common characteristics in all stages, most noticeable being the presence of a high number of vesicles distributed in a uniform way in the cytoplasm, and also the presence of numerous electron-dense mitochondria in many varied forms. The most important ultrastructural modifications took place at the 16-cell stage and affected, principally, the nucleus, which presented numerous condensations of chromatin distributed along the nucleoplasm. The nucleoli adopted a reticular morphology, abandoning the compact aspects presented in the previous stage. These changes might be involved in the synthesis of embryonic RNA, and, accordingly, in the activation of the genome of this species. These data indicate that this stage is critical to the embryonic development and might be related to the blockage produced in the development of cultivated sheep embryos at the point of transition from 8 to 16 cells. Nevertheless, it should be pointed out that the first signs of modifications in the aspect of the nucleus are observed at the four-cell stage, being characterized by the appearance of vacuolated areas in the nucleolus, indicating the first signs of embryonic nucleic activity, which would anticipate the main change in the control of the protein synthesis.     

Prolonged development of normal and parthenogenetic postimplantation mouse embryos in vitro

OBJECTIVE: To evaluate the efficacy of intracavernous moxisylyle versus placebo in patients with erectile dysfunction of various origins. To assess the local tolerance and systemic safety of moxisylyte by self-administered injection. METHODS: Multicentre study, comprising two treatment phases: The first, double-blind phase, was conducted in two parallel groups of randomized patients, over a 1-month period (1 injection per week) in the investigator's office; the second phase was conducted under open conditions in the patient's home, over a period of 3 to 11 months. Self-administered injections (1 to 2 per week) were performed using a prefilled syringe containing 10 mg of moxisylyte. RESULTS: Out of 307 patients evaluated during the first phase, the qualitative and quantitative superiority of erectile response induced by moxisylyte compared to placebo was confirmed (p < 0.0001). The stability of the response to moxisylyte was also confirmed on 4 injections, and the frequency of responses compatible with sexual intercourse ranged from 48% to 52% from one injection to another. This efficacy was also maintained during the open phase, as 92% of the 4,487 self-administered injections generated positive erectile responses. The quality of these responses was considered sufficient to allow sexual intercourse after 62% of injections. The local tolerance was considered to be excellent for more than 95% of injections, without any major adverse effects, and a very low risk of prolonged erection and fibrotic reaction. The systemic safety was also considered to be excellent for more than 98% of erections. CONCLUSION: This study confirms the possibility of obtaining an erectile response by intracavernous injection of 10 mg of moxisylyte with a very low incidence of local and systemic adverse effects. It also tends to confirm the superior efficacy of moxisylyte by self-administered injections at home than by injection in the doctor's office.     

Observations on early development of the murine fetal oral vestibule

The Spontaneous Selective Attention Task (SSAT) is a visual word-identification task that measures the type of selective attention that occurs spontaneously when there are multiple stimuli, all potentially relevant, and insufficient time to process each of them fully. The present study was designed to examine the sensitivity of the SSAT by comparing the performance of 40 schizophrenic inpatients and 30 schizophrenic outpatients to that of 70 normal controls. The pattern of results reported previously for schizophrenic inpatients versus normals was replicated, and these findings were extended to include schizophrenic outpatients in partial symptom remission. Schizophrenic inpatients and outpatients were just as accurate in identifying words as normals, but spontaneous selective attention under conditions of predictability was abnormal in both patient groups. Furthermore, the ability of the SSAT to discriminate between schizophrenic patients and controls was confirmed. A ratio measure of spontaneous selective attention had a sensitivity of 77% and a base rate of 9% in a normal population (when a cutoff value was set to minimize false positives and false negatives). Thus, the SSAT is a sensitive measure of an attentional phenotype that may be useful in genetic studies of schizophrenia.     

Expression of murine H1 histone genes during postnatal development

Connective tissue diseases encompass a wide group of nosologic entities of unknown etiology, characterized by multisystemic organ involvement, sharing an immunologic pathogenetic mechanism, producing a variety of inflammatory manifestations, and whose primary lesion is always a diffuse vasculitis. Any part of the cardiovascular system may be involved, including the pericardium, the myocardium, the endocardium and valves, the coronary arteries, the aorta, the pulmonary vasculature, the peripheral arteries, veins, arterioles, venules, and the capillary beds of almost every organ subsystem. Pathologic studies disclose a high prevalence of heart involvement, but the presence and extent of pathologic findings correlate poorly with clinical manifestations. With the advent of echocardiography-Doppler, milder and earlier cases are now recognized. Although these patients continue under the care of rheumatologists and internists, when cardiac involvement arises, cardiologists must be aware of the characteristics, outcome and management of connective tissue diseases.     

Endogenous retinoids in the early avian embryo

Vitamin A is required to rescue the vitamin A-deficient quail embryo from early death, but the endogenous presence of bioactive retinoids has not been documented in these embryos. The analysis of 2000 pooled stage 5-8 normal quail embryos described here provides for the first time direct evidence for the presence of endogenous all-trans-retinoic acid (5 nM) and 3,4-didehydroretinoic acid (4 nM), signaling molecules known to be potent ligands for nuclear retinoic acid receptors. The demonstration of all-trans-retinal (80 nM), all-trans-retinol (100 nM), 3,4-didehydroretinol (200 nM), and retinyl esters (100 nM) suggests the capability of the early avian embryo to generate in situ the vitamin A-bioactive molecules required for development. Analysis of 2100 pooled stage 5-8 quail embryos from vitamin A-deficient eggs revealed no vitamin A-like molecules, supporting the evidence that links vitamin A deficiency in these embryos to abnormalities and early death.     

Unequal cleavage in the early Tubifex embryo

The objective of this study was to generate and characterize monoclonal antibodies against rat airway mucins. Therefore, it should serve as a useful tool in studying the regulation of airway mucins using various in vivo rat models that are currently available. As an antigen, we used a high molecular mass mucin preparation purified from the spent media of rat tracheal surface epithelial cells in primary culture. Seven monoclonal hybridomas were obtained, among which mAbRT03 showed the highest immunoreactivity against the mucin. All of the antibodies secreted by these hybridomas recognized carbohydrate epitopes but not sialic acid residues, since their immunoreactivity was completely abolished by treatment of the mucin with 20 mM periodate but not with neuraminidase. Further characterization of mAbRT03 showed that (1) it belongs to the IgM type, (2) it binds to high molecular mass mucins based on Western blot, (3) it could indirectly immunoprecipitate rat airway mucin--and, as we know, this is the first demonstration of immunoprecipitation of airway mucin with anti-mucin antibodies--(4) it binds to the luminal side of tracheal epithelium as well as some goblet cells based on immunohistochemistry, and (5) it also recognizes in vivo airway mucins from rats, but not from human nor hamsters, which have been purified from the airway lavage fluids. This is the first monoclonal antibody against rat airway mucin, which has been developed against purified rat airway mucins. Therefore, mAbRT03 should be able to serve as an invaluable tool in studying the regulation of airway mucins using various intact rat models that are currently available.     

Expression of basement membrane type IV collagen chains during postnatal development in the murine cochlea

An immunofluorescence study was performed to examine the temporal and spatial patterns of expression for the different type IV collagen chains during postnatal cochlear development. At birth, the classical chains (4A1 and 4A2) were widely expressed, while the novel chains (4A3, 4A4, and 4A5) were completely absent. Activation of the novel chains was observed at 4 days of age, with intense, widely distributed immunostaining suggesting that most of the cells in the cochlea express the novel chains at this developmental stage. From day 8 through day 14, developmental inactivation of the novel chains results in a reduction of generalized immunoreactivity with a concomitant elevation of specific staining in the membranous structures bounding the interdental cells of the spiral limbus, the inner sulcus, the basilar membrane, and in a fibrous bed of staining radiating from the spiral prominence into the region of the spiral ligament which corresponds to the location of the root cell processes. This pattern of intense immunostaining for the novel chains persists through adulthood. The classical chains are expressed in these same anatomical regions only transiently (from day 6 to day 10), after which a gradual developmental inactivation leads to the adult expression pattern where classical collagen chains are found primarily in the perineurium, in the membranes surrounding the spiral ganglion cell bodies, and in the vascular basement membranes of the spiral ligament and the stria vascularis. The complex developmental pattern of expression for the type IV collagen chains in the murine cochlea is similar to that observed in the murine kidney, which is the other major site for basement membrane pathology in Alport syndrome.     

Identification of mRNA, localized at various segments of the Xenopus laevis embryo at early stages of the gastrula

METHODS: In a randomized double-blind study, 134 patients were given 500 mg metronidazole as an intravenous infusion immediately before operation for abdominal total hysterectomy and again 8 hours later and 124 patients received placebo. RESULTS: There was more wound infection, postoperative hospitalization was longer and the sedimentation rate on the sixth postoperative day was significantly higher in the placebo group. There was no difference in postoperative temperature. Postoperative wound infections occurred in 12% in the placebo group and 6% in the metronidazole group. Eight percent in the total material had urinary tract infections, the diagnosis was based on urine cultures. CONCLUSIONS: Prophylaxis with intravenous infusion of metronidazole is recommended in total hysterectomies.     

Tubular up-regulation of clusterin mRNA in murine lupus-like nephritis

Clusterin, a widely distributed glycoprotein, is detected in most tissues and in numerous physiological fluids. In the kidney, this protein is constitutively expressed in tubular epithelial cells, and its expression is enhanced following tubular injuries. In addition, clusterin has been detected in glomerular immune deposits of glomerulonephritis. The present study was designed to define the sites of clusterin mRNA accumulation in murine lupus-like nephritis in comparison with murine tubulopathies. In lupus-like nephritis, a significant increase of clusterin mRNA abundance was demonstrated. This up-regulation was localized exclusively in tubular epithelial cells exhibiting tubulointerstitial alterations, whereas no clusterin mRNA was detectable in diseased glomeruli, excluding an active synthesis of clusterin by glomerular cells. A similar tubular increase of clusterin mRNA abundance was observed in myeloma-like cast nephropathy induced by IgG3 monoclonal cryoglobulins and even in the absence of any detectable histological alterations in a model of septic shock induced by the injection of bacterial lipopolysaccharides. Our results suggest that tubular epithelial cells are the only sites of clusterin mRNA accumulation during the course of lupus-like nephritis and that the tubular up-regulation of clusterin gene expression may reflect the cellular response to various types of tubular injuries.     

Chick embryo development can be irreversibly altered by early exposure to weak extremely-low-frequency magnetic fields

Several reports have shown that weak, extremely-low-frequency (ELF), pulsed magnetic fields (PMFs) can adversely affect the early embryonic development of the chick. In this study, freshly fertilized chicken eggs were exposed during the first 48 h of postlaying incubation to PMFs with 100 Hz repetition rate, 1.0 microT peak-to-peak amplitude, and 500 microseconds pulse duration. Two different pulse waveforms were used, having rise and fall times of 85 microseconds (PMF-A) or 2.1 microseconds (PMF-B). It has been reported that, with 2 day exposure, these fields significantly increase the proportion of developmental abnormalities. In the present study, following exposure, the eggs were allowed to incubate for an additional 9 days in the absence of the PMFs. The embryos were taken out of the eggs and studied blind. Each of the two PMF-exposed groups showed an excess in the percentage of developmental anomalies compared with the respective sham-exposed samples. This excess of anomalies was not significant for the PMF-A-treated embryos (P = 0.173), whereas it was significant for the PMF-B-exposed group (P = 0.007), which showed a particularly high rate of early embryonic death. These results reveal that PMFs can induce irreversible developmental alterations and confirm that the pulse waveform can be a determinant factor in the embryonic response to ELF magnetic fields. The data also validate previous work based on the study of PMFs' effects at day 2 of embryonic development under field exposure.     

Insulin synthesis in chick embryo retinas during development

Retinas of chick embryos contain insulin and further, are capable of synthesizing it, as demonstrated by incubating retinas at different ages (7th-18th day) with [3H]leucine. The synthesized radioactive insulin was isolated and assayed by means of a HPLC procedure. The synthesis of insulin was found to be highest in the youngest retinas studied (day 7), afterwards it declined with age except for an increment found at 14-15 day. Explants of chick embryo retinas, cultured in vitro, rapidly degraded insulin. Nevertheless, the content of immunoreactive insulin in retinal explants diminished slowly with the age of culture, so that, after 8 days of incubation, it was about 60% of the content found in the retinas at the beginning of incubation. This was proof that cultured explants are capable of efficiently synthesizing insulin. The synthesized [3H]insulin was released from explants into the medium. This was evident also after 6-8 days in culture.     

Permanent impairment of embryo development by hydrosalpinges

Recent reports suggest a deleterious effect of hydrosalpinges on pregnancy outcome for in-vitro fertilization (IVF) and improvement following surgical treatment. We compared the effect of hydrosalpinx on pregnancy outcome in 286 patients having 348 IVF cycles and followed the development of untransferred embryos for 7 days to determine if hydrosalpinges affect oocyte quality or embryo development. The delivery rate per retrieval was significantly lower for patients with hydrosalpinx, but was restored by surgical treatment to that of patients without hydrosalpinx. However, the implantation rate per embryo transferred and normal blastulation of untransferred embryos, which were significantly decreased in patients with hydrosalpinx, and growth arrest and degeneration of untransferred embryos, which were significantly increased compared to patients without hydrosalpinx, were not restored by surgical treatment of hydrosalpinges. We conclude that surgical treatment of hydrosalpinges decreases early pregnancy loss and improves pregnancy outcome, possibly by diminishing reversible deleterious effects exerted on the endometrium. As we have seen in our laboratory, hydrosalpinges may have a permanent negative influence on ovarian function, follicular development and oocyte quality since implantation of transferred embryos and normal blastulation of untransferred embryos remain low, and in-vitro growth arrest and degeneration remain high despite surgical treatment of hydrosalpinges.