1/49. Pharyngeal pituitary: development, malformation, and tumorigenesis.The development of the pharyngeal pituitary (PhP) in the fetal period was morphologically and, for the first time, immunohistochemically examined. PhP, found in every individual, begins its hormone production at the 17-18th week of gestation, that is, 4-8 weeks later than that of sellar pituitary (SP). Only 1 of 25 examined fetuses without any stigmata of developmental anomalies showed a residual pituitary fragment in the craniopharyngeal canal (craniopharyngeal pituitary, CPhP). An adult case of a rare clivus pituitary adenoma that we examined is demonstrated in discussing its relationship to PhP. Extracranial ectopic pituitary adenomas in the literature describe an exclusively sphenoid sinus/nasopharyngeal/clivus location of the tumor. Their location corresponded exactly with that of PhP, so that the origin of the tumors can be reasonably speculated as PhP, although another origin, e.g., CPhP, can not be excluded. A variety of malformations of PhP, although very rare, have been described for the fist time during the systemic examination of 16 fetuses with different cranioneural malformations, such as agenesis, unseparated PhP from SP (pharyngosellar pituitary), fragmentation, and residual pituitary tissue in the open craniopharyngeal canal. However, developmental anomaly of PhP was not specifically associated with cranioneural malformations except in cases of chromosomal aberrations. The hormone production in PhP in malformation cases tended to be retarded. Absence of SP was recorded in 50% of anencephalics in the literature; however, PhP was identified in all anencephalics in our series, independent of the existence of SP. This supports the opinion that agenesis of SP in anencephalics seems to be false information.- - - - - - - - - - ranking = 1keywords = ring (Clic here for more details about this article) |
2/49. trisomy 2p syndrome: a fetus with anencephaly and postaxial polydactyly.We report on a male fetus with partial trisomy 2p21-2pter and monosomy 15q26-15qter due to t(2,15)(p21;q26). This fetus had a typical trisomy 2p phenotype including minor facial anomalies, musculoskeletal defects and two unusual findings: polydactyly and anencephaly. The observation of anencephaly adds support to the theory that genetic material mapping to chromosome band 2p24 is involved in neural tube development. In addition, we propose that a gene on 2p23 may play a role in the morphogenetic patterning of hands and feet.- - - - - - - - - - ranking = 8.0908896699976keywords = chromosome (Clic here for more details about this article) |
3/49. prenatal diagnosis of mosaic ring chromosome 13 with anencephaly.We report on the prenatal diagnosis, genetic analysis and clinical manifestations of a second-trimester fetus with mosaic ring chromosome 13 and anencephaly. A 35-year-old, gravida 3, para 2 woman was referred for genetic counselling at 23 weeks' gestation because of an elevated maternal serum alpha-fetoprotein level of 2.386 multiples of the median. Prenatal ultrasonography showed intrauterine growth retardation and anencephaly. amniocentesis revealed a karyotype of de novo mos 46,xx,r(13)(p11q32)/45,xx,-r(13) [corrected] (77%/23%). Molecular genetic analysis by quantitative fluorescent polymerase chain reaction (PCR) with small tandem repeat markers specific for chromosome 13 rapidly confirmed the maternal origin of the aberrant chromosome and determined the breakpoint at 13q32 between D13S225 (present) and D13S147 (absent). Our present finding indicates that anencephaly can be due to mosaic r(13) with a terminal deletion of 13q32-13q34 and an additional secondary rearrangement of loss of r(13). We propose that cytogenetic analysis is beneficial and warranted in pregnancies with fetal neural tube defects.- - - - - - - - - - ranking = 649.25334491152keywords = ring chromosome, chromosome, ring (Clic here for more details about this article) |
4/49. Early ultrasound diagnosis of Neu-Laxova syndrome.We report the mid-trimester prenatal diagnosis of Neu-Laxova syndrome (NLS) in two at risk families utilizing serial sonographic examinations. Ultrasound and pathologic findings from seven affected pregnancies, the largest case series of NLS to date, are presented. One fetus had anencephaly and incomplete rachischisis, an anomaly that has not been previously reported in association with NLS. Ultrasonographic detection of severe intrauterine growth restriction (IUGR), abnormally postured limbs, microcephaly, and edema allowed prenatal diagnosis of NLS in five of these at risk pregnancies during the mid-trimester. growth curves derived from serial sonograms reveal abnormalities of all standard biometric measurements. The growth discrepancy was most pronounced in the measurements of the biparietal diameter, which were consistently less than two standard deviations below the mean across all gestational ages. This case series confirms that aberrant growth and anomalies may be detected sufficiently early in gestation to permit prenatal diagnosis of NLS.- - - - - - - - - - ranking = 1keywords = ring (Clic here for more details about this article) |
5/49. Use of a temporary vena cava filter in a woman with septic abortion and inferior vena cava thrombosis. A case report.BACKGROUND: Ovarian vein and inferior vena cava (IVC) thrombosis are rare but life-threatening complications of severe obstetric infections. IVC filters have been used to reduce the risk of pulmonary embolus in patients who have recurrent thrombotic and embolic events or underlying risk factors. More recently, retrievable IVC filters have been used in patients in whom the risk is transient. CASE: At 18 weeks' gestation a multigravida with a fetus with anencephaly became septic after laminaria placement and rupture of the membranes. She developed ovarian vein and IVC thrombosis and was treated successfully with a retrievable IVC filter, anticoagulation and antibiotics. The filter was removed after 9 days. CONCLUSION: In young patients at transient risk for emboli and requiring placement of an IVC filter, a retrievable filter should be considered to reduce the long-term risks of an indwelling filter.- - - - - - - - - - ranking = 1keywords = ring (Clic here for more details about this article) |
6/49. The smile in anencephalic infants.During the period 1947-1959 twelve new-born mero-anencephalics were observed, who survived for more than 1 day after birth. Two even lived for 20 and 237 days, respectively. In 4 of the 12 children studied touching or slight pressure, and also faradic stimulation of various spots of the cerebro-vascular area were invariably followed by a facial expression which was very similar to smiling. Movies of it were shown to groups of impartial observers. In 78% the facial expression was judged to be a smile, a laugh or a grin. The neuroanatomical finding of a largely intact pontine tegmentum as being the most rostrally situated identifiable structure of the brainstem, has led to the hypothesis that the neural mechanisms underlying the smile are localized in the pontine tegmentum.- - - - - - - - - - ranking = 1keywords = ring (Clic here for more details about this article) |
7/49. High levels of maternal serum alpha-fetoprotein and human chorionic gonadotrophins leading to the diagnosis of combined neural tube defect and partial mole.A case of combined partial mole and neural tube defect is presented. The detection of high levels of both maternal serum (MS) alpha-fetoprotein (AFP) and human chorionic gonadotrophin (hCG) during the second trimester led to the ultrasonic demonstration of anencephaly, omphalocele, and partial mole. This is the first report of combined elevation of MSAFP and MShCG.- - - - - - - - - - ranking = 1keywords = ring (Clic here for more details about this article) |
8/49. Ring chromosome 13: lack of distinct syndromes based on different breakpoints on 13q.A stillborn male child with anencephaly and multiple malformations was found to have the karyotype 46,XY,r(13) (p11q21.1). The breakpoint at 13q21.1, determined by high resolution banding, is the most proximal breakpoint ever reported in patients with ring chromosome 13. In situ hybridisation with the probe L1.26 confirmed the derivation from chromosome 13 and dna polymorphism analysis showed maternal origin of the ring chromosome. Our results, together with a review of previous reports of cases with ring chromosome 13 with identified breakpoints, could neither support the theory of distinct clinical syndromes based on different breakpoints on 13q nor correlate the severity of symptoms with instability of the ring.- - - - - - - - - - ranking = 421.2973876929keywords = ring chromosome, chromosome, ring (Clic here for more details about this article) |
9/49. klippel-feil syndrome plus atretic meningocele in one identical twin and anencephaly in the other.klippel-feil syndrome (KFS) is a heterogeneous entity, characterized by specific congenital anomalies of segmentation of the cervical spine. We report a case of KFS plus atretic meningocele in one identical twin and anencephaly in the other. These identical twins were both male with no chromosome defect. One of them had anencephaly diagnosed at the gestational age of 17 weeks and died soon after birth, whereas the co-twin had KFS with multiple congenital anomalies including short neck with low hairline, occipital atretic meningocele, butterfly vertebrae, hemivertebrae, cervico-thoracic scoliosis, left thumb preaxial polydactyly, and right undescended testis. He received rehabilitation during infancy and could walk at the age of 15 months. Both of these infants had preaxial polydactyly, which is an uncommon anomaly associated with KFS. In conclusion, iniencephaly and anencephaly are probably the extreme manifestations of KFS rather than different dysraphisms. Prompt clinical suspicion with early diagnostic imaging for spine lesions and occult opening of neural tube is mandatory for further intervention and rehabilitation.- - - - - - - - - - ranking = 9.0908896699976keywords = chromosome, ring (Clic here for more details about this article) |
10/49. Partial duplication 2p as the sole abnormality in two cases with anencephaly.anencephaly/NTD has been observed in aneuploid and non-aneuploid individuals. We present two cases of anencephaly diagnosed prenatally with partial duplication of the short arm of chromosome 2 as the sole abnormality. The absence of aneuploidy involving other regions of the genome in these cases, further substantiates suggestions of the existence of a gene or genes on the short arm of chromosome 2 critical in the development of the central nervous system.- - - - - - - - - - ranking = 16.181779339995keywords = chromosome (Clic here for more details about this article) |
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