Morpholino phenocopies of sqt, oep, and ntl mutations.
Explore the source record for details and available documents.
Animals↗
Biomedical subjects
B Feldman
Publications and source records attributed to B Feldman.
First-trimester embryo size discordance: a predictor of premature birth following multifetal pregnancy reduction.
OBJECTIVE: We have previously reported a correlation between the starting number of embryos for multifetal pregnancy reduction (MFPR) and discordance in size during the first trimester. Here we evaluated the correlation between the degree of discordance and length of gestation in the remaining fetuses. DESIGN: Observational clinical series. SETTING: Academic medical center with a single physician who performs a large number of MFPRs. PATIENT(S): Analysis of 252 consecutive MFPRs from a 2.5-year period (1996-1998). INTERVENTION(S): MFPR for patients with multifetal pregnancies. MAIN OUTCOME MEASURE(S): We evaluated the correlation between the degree of discordance in embryo size, as measured by the greatest difference in crown-rump length (CRL) (delta max), and the length of gestation. RESULT(S): Embryo size discordance was related to length of gestation of the remaining fetuses after MFPR. Of 72 patients with a delta max >5 mm, the rate of severe premature birth (delivery at <28 weeks' gestation) was 9.7%, compared with 1.7% for patients with a delta max <5 mm (P<.01). Of patients with severe premature birth, 70% had delta max >5 mm, compared with less than 30% in patients who delivered after 28 weeks (P<.05). CONCLUSION(S): Variations in embryo growth patterns in multifetal pregnancies may be observed even in the first trimester, which may be predictive of late pregnancy outcomes. With a delta max > or =5 mm, there is a significant increase in the risk of severe premature birth (delivery at <28 weeks).
Crown-Rump Length↗
The randomized placebo-phase design for clinical trials.
Randomized controlled trials are the criterion standard method for evaluating the effectiveness of medical treatments. There are situations, however, where the possibility of being in the control group in a randomized controlled trial is unacceptable to potential subjects or their physicians. This lack of acceptance is a reason for poor accrual. We developed and validated a new clinical trial design for survival data that may allay concerns about not receiving an investigational product and should be more acceptable. Called the randomized placebo-phase design, this new design asks whether, on average, those subjects who begin active treatment sooner respond sooner than those who begin it later. Using Monte Carlo computer simulations, we demonstrated that the design is valid and may offer advantages over traditional randomized controlled trials in some situations. The randomized placebo-phase design may be especially useful when highly potent therapies for rare diseases are tested or when accrual may be otherwise difficult.
Humans↗
Correlations between motor persistence and plasma levels in methylphenidate-treated boys with ADHD.
Following a 0.9 mg/kg methylphenidate loading dose, serial plasma level determinations, self-scored mood ratings, and measures of motor persistence were gathered on eight previously unmedicated boys with attention deficit disorder with hyperactivity (ADHD) during a 9-h period. The measures were repeated using the same loading dose after 6 months of maintenance treatment with methylphenidate (1.3 mg/kg x d). Kinetic-dynamic modelling suggests inverse correlative relationships between motor performance errors and plasma levels. Pharmacokinetic parameters did not change between acute and maintenance drug treatment phases, and there was no evidence of long-term tolerance.
Adolescent↗
Octreotide reduces vitreous hemorrhage and loss of visual acuity risk in patients with high-risk proliferative diabetic retinopathy.
OBJECTIVE: Growth hormone and insulin-like growth factor-I have been implicated as strong promoters of proliferative diabetic retinopathy. We studied reduction of bleeding and preservation of visual acuity by treatment with the long-acting somatostatin analogue, octreotide, in diabetic patients at an advanced stage of proliferative diabetic retinopathy. RESEARCH DESIGN AND METHODS: Randomized trial in a University hospital setting. Reading ophthalmologists were masked for octreotide use, diabetologists were aware of that treatment. Nine patients received 100 microg tid octreotide (verum) subcutaneously for a maximum of 36 months. Nine diabetics served as controls, no placebo treatment was used. Episodes of vitreous hemorrhages were counted, measurement of visual acuity, estimation of neovascularization by stereoscopic fundus photography and fluorescein angiography were carried out. RESULTS: After 3 years of treatment, the incidence of vitreous hemorrhages and the need for vitreoretinal surgery was significantly lower (log rank test p = 0.002) in the octreotide-treated patients. Visual acuity was preserved and significantly better in the octreotide treated group compared to controls (p = 0.05). CONCLUSIONS: In diabetics with high-risk proliferative retinopathy after full scatter laser coagulation, octreotide reduced the number of vitreous hemorrhages, preserving visual acuity.
Adult↗
Microbiology of serous otitis media in children: correlation with age and length of effusion.
The purpose of this study was to correlate the microbiology of serous otitis media in children with the duration of the condition and the patient's age. Aspirates of serous ear fluids from 114 children were examined for aerobic and anaerobic bacteria. Bacterial growth was noted in 47 patients (41%). Aerobic organisms only were recovered in 27 aspirates (57% of the culture-positive aspirates); anaerobic bacteria only in 7 (15%); and mixed aerobic and anaerobic bacteria in 13 (28%). A total of 83 bacterial isolates were recovered, accounting for 1.8 isolates per specimen (1.2 aerobes and 0.6 anaerobe). There were a total of 57 aerobic isolates, including Haemophilus influenzae (15 isolates), Streptococcus pneumoniae (13), and Staphylococcus sp (12). Twenty-six anaerobes were recovered, including anaerobic gram-positive cocci (10), Prevotella spp (8), and Propionibacterium acnes (4). The rate of positive cultures (20 of 36; 56%) was higher in patients younger than 2 years of age than in those older than 2 years of age (27 of 78; 35%). Streptococcus pneumoniae and H influenzae were more often isolated in children younger than 2 years of age and those with effusion for 3 to 5 months, whereas anaerobes were recovered more often in those older than 2 years of age and those with effusion for 6 to 13 months. These data illustrate the effects of the length of effusion and age on the recovery of aerobic and anaerobic bacteria in serous otitis media.
Age Factors↗
In vitro fertilization following natural cycles in poor responders.
This prospective study was designed to examine the feasibility of natural cycle in vitro fertilization (IVF) in poor responders, and the clinical factors that may predict successful outcome. Twenty-two poor responders underwent IVF treatment with 44 unstimulated cycles. The results of the natural cycles were compared with those of the 55 low-response stimulated cycles of these patients during the 12 months prior to the study. Eighteen (82%) patients had at least one oocyte retrieved, while nine (41%) had at least one cycle with embryo transfer. Two (9%) patients each gave birth to a healthy term baby. These results are comparable with those of the stimulated cycles. Serum early follicular follicle stimulating hormone (FSH) level was found to be the only reliable predictor of oocyte recovery and overall outcome in each specific natural cycle. However, because of great variability in basal FSH levels among different cycles of the same patient, this is not a reliable predictor of outcome in future cycles. We conclude that poor responders are a unique group of patients who may benefit from natural-cycle IVF treatment.
Adult↗
Nodal-related signals establish mesendodermal fate and trunk neural identity in zebrafish.
The vertebrate body plan arises during gastrulation, when morphogenetic movements form the ectoderm, mesoderm, and endoderm. In zebrafish, mesoderm and endoderm derive from the marginal region of the late blastula, and cells located nearer the animal pole form the ectoderm [1]. Analysis in mouse, Xenopus, and zebrafish has demonstrated that Nodal-related proteins, a subclass of the TGF-beta superfamily, are essential for mesendoderm development [2], but previous mutational studies have not established whether Nodal-related signals control fate specification, morphogenetic movements, or survival of mesendodermal precursors. Here, we report that Nodal-related signals are required to allocate marginal cells to mesendodermal fates in the zebrafish embryo. In double mutants for the zebrafish nodal-related genes squint (sqt) and cyclops (cyc) [3] [4] [5], dorsal marginal cells adopt neural fates, whereas in wild-type embryos, cells at this position form endoderm and axial mesoderm. Involution movements characteristic of developing mesendoderm are also blocked in the absence of Nodal signaling. Because it has been proposed [6] that inhibition of Nodal-related signals promotes the development of anterior neural fates, we also examined anteroposterior organization of the neural tube in sqt;cyc mutants. Anterior trunk spinal cord is absent in sqt;cyc mutants, despite the presence of more anterior and posterior neural fates. These results demonstrate that nodal-related genes are required for the allocation of dorsal marginal cells to mesendodermal fates and for anteroposterior patterning of the neural tube.
Animals↗
Routine prenatal diagnosis of aneuploidy by FISH studies in high-risk pregnancies.
This study is a prospective clinical trial with fluorescent in situ hybridization (FISH) as a "routine" test for prenatal detection of the most common aneuploidies in high-risk pregnancies. Since April 1996, FISH studies with multicolor, commercially available, specific probes for chromosomes 13, 18, 21, X, and Y have been routinely performed in our cytogenetic laboratory on uncultured chorionic villous samplings (CVS), amniotic fluid samples, or fetal blood obtained by cordocentesis from patients with major or minor fetal anomalies detected by ultrasonography. Among the 4,193 prenatal samples analyzed between April 1996 and June 1998, routine FISH studies were ordered by the referring physicians on 301 (7.2%) cases. Aneuploidies were detected in 32 (10.6%) samples. Fourteen trisomy-21, 10 trisomy-18, 3 trisomy-13, 4 monosomies of X, and 1 case of triploidy were diagnosed by FISH. All 1,505 hybridizations were informative, and all 301 results were available and reported to the referring physicians in 24-48 hr. All relevant FISH results were confirmed by subsequent cytogenetic analysis. In 10 (3.8%) cases with normal FISH results, the final cytogenetic analysis revealed abnormal chromosomal rearrangements that could not be detected by the routine FISH studies. We conclude that rapid FISH analysis of interphase, uncultured fetal cells is an accurate and very sensitive method for routine prenatal diagnosis of the most common aneuploidies in high-risk pregnancies.
Aneuploidy↗
Rapid confirmation of previously detected prenatal mosaicism by fluorescence in situ hybridization in interphase uncultured amniocytes.
Fluorescence in situ hybridization (FISH) of chromosome-specific probes to interphase uncultured amniocytes was performed in cases in which follow-up amniocenteses were done for confirmation of previously detected mosaicism. FISH results were informative in all seven cases included in the study, and confirmed by subsequent cytogenetic analysis. FISH analysis provides rapid results for referral physicians and in most cases reassurance for patients within 24 hours of the follow-up aminocentesis. Although FISH studies are not considered accurate in determining a primary diagnosis of mosaicism in uncultured cells, the analysis is accurate and clinically useful when the diagnosis is known and mosaicism involving a specific chromosome needs to be confirmed in follow-up testing.
Amniocentesis↗
FreeStyle: a small-volume electrochemical glucose sensor for home blood glucose testing.
FreeStyle accurately measures the concentration of glucose in a 300-nL volume of capillary blood obtained with significantly reduced pain from the forearm where the density of capillaries is much lower than in the fingertips. The readings are independent of temperature, of altitude (O2 pressure) and of hematocrit in the 0%-60% range. At their physiological levels, none of the often interfering constituents of blood affect the readings.
Blood Glucose↗
Analysis of chromosomal rearrangements induced by postmeiotic mutagenesis with ethylnitrosourea in zebrafish.
Mutations identified in zebrafish genetic screens allow the dissection of a wide array of problems in vertebrate biology. Most screens have examined mutations induced by treatment of spermatogonial (premeiotic) cells with the chemical mutagen N-ethyl-N-nitrosourea (ENU). Treatment of postmeiotic gametes with ENU induces specific-locus mutations at a higher rate than premeiotic regimens, suggesting that postmeiotic mutagenesis protocols could be useful in some screening strategies. Whereas there is extensive evidence that ENU induces point mutations in premeiotic cells, the range of mutations induced in postmeiotic zebrafish germ cells has been less thoroughly characterized. Here we report the identification and analysis of five mutations induced by postmeiotic ENU treatment. One mutation, snh(st1), is a translocation involving linkage group (LG) 11 and LG 14. The other four mutations, oep(st2), kny(st3), Df(LG 13)(st4), and cyc(st5), are deletions, ranging in size from less than 3 cM to greater than 20 cM. These results show that germ cell stage is an important determinant of the type of mutations induced. The induction of chromosomal rearrangements may account for the elevated frequency of specific-locus mutations observed after treatment of postmeiotic gametes with ENU.
Animals↗
Prenatal evaluation of a de novo X;9 translocation.
A case of X-autosome translocation was diagnosed prenatally [46,X, t(X;9)(p21.3 approximately 22.1;q22]. We describe the use of fluorescence in situ hybridization (FISH) to estimate the integrity of the Duchenne muscular dystrophy (DMD) gene. X-inactivation studies were used as well to assess the probability of phenotypic abnormalities associated with functional partial disomy X and monosomy 9.
Adult↗
Prenatal diagnosis of 46,XY/46,XX mosaicism: a case report.
We report on the prenatal diagnosis of a fetus with 46,XY and 46,XX cell lines with a normal male phenotype. Cytogenetic and molecular studies ruled out the possibility of maternal cell contamination and showed that all the X chromosomes present in both fetal cell lines were derived from a single maternal X chromosome. This suggests 46,XY/46,XX mosaicism.
Alleles↗
Molecular cytogenetic analysis of a de novo 5q31q33 deletion associated multiple congenital anomalies: case report.
Interstitial deletions are relatively rare chromosomal anomalies that usually arise de novo. The data describing the phenotype associated with interstitial deletions of 5q are very limited. We describe the first case of multiple fetal anomalies, diagnosed on prenatal sonographic examination, associated with a deletion at 5q31q33. Sonographic examination at 23 weeks' gestation demonstrated growth parameters consistent with 20 weeks' gestation; a 7-mm nuchal fold; a dilated loop of bowel adjacent to the stomach suggestive of duodenal atresia; clubbing of the left foot; a narrow aorta; suspected ventricular septal defect; and placental thickening. The patient delivered a severely growth-restricted fetus and enlarged placenta at 30 weeks' gestation. The infant died neonatally.
Adult↗
Genomic organization and embryonic expression of the mouse fibroblast growth factor 9 gene.
Fibroblast growth factor 9 (FGF9), originally cloned as glial-activating factor from human glioma cells, is expressed in adult rat brain and kidney. Here we report the chromosomal localization, genomic organization, and embryonic expression pattern of the mouse Fgf9 gene. Fgf9 maps to chromosome 14 near the Ctla6 locus. The gene spans more than 34 kb and contains three exons and two introns. Translation initiation occurs in exon 1, and translation termination occurs in exon 3. Fgf9 RNA was detected during mouse embryogenesis in several tissues in which Fgf gene expression has not been previously described, including intermediate mesoderm of late-stage gastrulation, ventricular myocardium, lung pleura, skeletal myoblasts in the early limb bud, spinal cord motor neurons, olfactory bulb, and gut lumenal epithelium. Fgf9 is coexpressed with other Fgf genes in some skeletal myoblasts, in limb apical ectoderm, in craniofacial ectoderm, and in the retina, inner ear, and tooth bud. Dev Dyn 1999;216:72-88.
Amino Acid Sequence↗
In-vitro fertilization treatment for severe male factor: the fertilization potential of immotile spermatozoa obtained by testicular extraction.
A retrospective analysis in 50 couples of 53 cycles of intracytoplasmic sperm injection (ICSI) with immotile spermatozoa from testicular-retrieved spermatozoa was performed to evaluate whether total immotile spermatozoa achieved after testicular sperm extraction could fertilize ova and result in pregnancies. We assessed the efficacy of ICSI with totally immotile testicular spermatozoa extracted from the testes of azoospermic patients with severe spermatogenic failure (group 1) and compared these results with those from spermatozoa which were recovered after several hours of incubation and were motile (group 2) at the time of injection. In 19 cycles, only totally immotile spermatozoa were injected at the time of ICSI. For the remaining 34 cycles, at least one motile spermatozoon was found for injection. The oocyte fertilization rates were 51% for group 1 and 62% for group 2 (P < 0.02). Eighteen of 19 cycles in group 1 (90%) and all 34 (100%) cycles in group 2 had embryos for replacement. The mean number of embryos per cycle was 5.2 +/- 0.8 and 7.5 +/- 0.9 in groups 1 and 2 respectively; this and the embryo quality (cumulative embryo scoring = 40 +/- 8 for group 1 and 50 +/- 7 for group 2), and clinical pregnancy rates (15.8% per oocyte retrieval in group 1 and 23.5% in group 2) were not significantly different between groups. Fertilization, cleavage and pregnancy can be achieved with intracytoplasmic testicular sperm injection from patients with immotile spermatozoa, at levels comparable with those of ICSI using motile spermatozoa.
Adult↗
Zebrafish organizer development and germ-layer formation require nodal-related signals.
The vertebrate body plan is established during gastrulation, when cells move inwards to form the mesodermal and endodermal germ layers. Signals from a region of dorsal mesoderm, which is termed the organizer, pattern the body axis by specifying the fates of neighbouring cells. The organizer is itself induced by earlier signals. Although members of the transforming growth factor-beta (TGF-beta) and Wnt families have been implicated in the formation of the organizer, no endogenous signalling molecule is known to be required for this process. Here we report that the zebrafish squint (sqt) and cyclops (cyc) genes have essential, although partly redundant, functions in organizer development and also in the formation of mesoderm and endoderm. We show that the sqt gene encodes a member of the TGF-beta superfamily that is related to mouse nodal. cyc encodes another nodal-related proteins, which is consistent with our genetic evidence that sqt and cyc have overlapping functions. The sqt gene is expressed in a dorsal region of the blastula that includes the extraembryonic yolk syncytial layer (YSL). The YSL has been implicated as a source of signals that induce organizer development and mesendoderm formation. Misexpression of sqt RNA within the embryo or specifically in the YSL induces expanded or ectopic dorsal mesoderm. These results establish an essential role for nodal-related signals in organizer development and mesendoderm formation.
Amino Acid Sequence↗