Mythos and logos in Hesiod's Theogony,circa 700 B.C.

Hesiod's Theogony, a completely preserved poem, is dated from about 700 B.C. It depicts partly a development, partly a situation that has arisen in the course of time in the world. It constitutes an attempt to understand the cosmos as the product of a genealogical evolution, which can be seen as a process of successive separation, differentiation, and hierarchization. In this attempted picture of the world myth and reality are inextricably interwoven. Observations of natural phenomena as far as of congenital malformations are accordingly exaggerated and undergone mythical transformation. Entities enumerated in this genealogical poem, no matter whether they stand for parts and concrete phenomena of the physical world or intellectual properties and abstract concepts, behave, think, and act, and are accordingly thought of, in anthropomorphic terms. Monogamy, polygamy, endogamy, exogamy, asexual and sexual reproduction, multiple conceptions and births, dominantly and recessively inherited traits, normal and abnormal offspring, and perceptions and notions on cosmogony, isogamy, and teratogenesis could be observed in the writing of the Theogony and interpreted by rational modern concepts. © 1996 Wiley-Liss, Inc.     

Correlations of placental vascular anatomy and clinical outcomes in 69 monochorionic twin pregnancies

Monochorionic monozygotic twins frequently suffer complications from the presence of vascular anastomoses in their monochorionic placentas. Also, sharing of perfusion zones may be unequal, leading to marked growth discordance. This paper analyzes four measures of perinatal outcome (gestational age at delivery, perinatal mortality, birth weight discordance, and presence/absence of hydramnios) according to the vascular patterns of the monochorionic placentas. The worst clinical outcomes were associated with arteriovenous anastomoses in the absence of arterio-arterial and veno-venous anastomoses. The vascular patterns of monochorionic placentas cause significant fetal environmental differences within pairs of monochorionic monozygotic twins. These differences may cause life-long discordance for several phenotypic traits that are not genetically based, and which cause monochorionic monozygotic twins to be “non-identical.” © 1996 Wiley-Liss, Inc.     

X-chromosome inactivation is mostly random in placental tissues of female monozygotic twins and triplets

Patterns of X-chromosome inactivation in chorion, amnion, and cord from 79 pairs of twins were examined. Seven sets of triplets were included in the analysis, both as twin pairs and triplets. Twins were stratified as dizygotic (DZ), monozygotic (MZ), monochorionic, and dichorionic and were selected for birth weight discordance, discordance for congenital anomalies, twin-twin transfusion syndrome, and various patterns of vascular anastomosis. X-inactivation was predominantly symmetric. Chorion was the most likely tissue to show asymmetric X-inactivation and was found most frequently in MZ dichorionic twins. There was no correlation of X-inactivation pattern with the selected clinical criteria. This study does not confirm that asymmetric X-inactivation in embryonic tissues is a common phenomenon in female twins, including monozygotic twins. © 1996 Wiley-Liss, Inc.     

Blood group chimerism in human multiple births is not rare

Twin blood group chimerism seems to be very rare in humans. The 30–40 previously reported cases usually were found by mere coincidence during routine blood grouping in hospitals or blood banks. Usually in these cases frank blood group mixtures of, for example, 50/50%, 25/75%, or 5/95% at most were seen. Smaller percentages are very difficult to notice during routine work-up. Using a sensitive fluorescence technique (sensitivity >0.01%) we detected blood group chimerism in 32/415 (8%) twin pairs and 12/57 (21%) triplet pairs, respectively, which is a higher incidence than reported previously. © 1996 Wiley-Liss, Inc.     

Twin Anemia Polycythemia Sequence: Knowledge and Insights After 15 Years of Research

Twin anemia polycythemia sequence (TAPS) is a chronic form of unbalanced feto-fetal transfusion through minuscule placental anastomoses in monochorionic twin pregnancies, leading to anemia in the donor twin and polycythemia in the recipient twin. TAPS can occur spontaneously in up to 5% of monochorionic twins or can arise in 2%-16% of cases after incomplete laser surgery for twin-twin transfusion syndrome. TAPS can develop across the entire second and third trimester. Antenatal diagnosis for TAPS is reached via Doppler measurement of the fetal middle cerebral artery peak systolic velocity, showing an increased velocity in the donor, combined with a decreased velocity in the recipient. Treatment options for TAPS include expectant management, preterm delivery, intrauterine blood transfusion with or without a partial exchange transfusion, fetoscopic laser surgery and selective feticide. The best treatment option is unclear and is currently being investigated in an international multicenter randomized trial (the TAPS trial). Spontaneous fetal demise occurs in 5%-11% of TAPS twins, more often in donors (8%-18%) than in recipients (2%-5%). Severe long-term neurodevelopmental impairment is seen in 9% of TAPS twins, with donors having an increased risk for cognitive impairment and hearing problems (15%).     

Analysis of c-kit exon 11 and exon 17 of urticaria pigmentosa that occurred in monozygotic twin sisters

Genomic DNA extracted from peripheral blood mononuclear cells of monozygotic twin patients with urticaria pigmentosa was investigated for mutations of proto-oncogene c-kit. Neither the patients nor their families had genomic mutations in exon 11 or exon 17 of c-kit. The patients did not have any systemic involvement or bone marrow abnormalities. There are indications that some genetic factors may participate in the pathogenesis of urticaria pigmentosa in monozygotic twins. In the present patients, factors other than genomic faults in exon 11 and exon 17 of c-kit may be responsible for the pathogenesis.     

Supraventricular Electrical Interaction in Conjoined Twins with Common Coronary Sinus

Conjoined twins with echocardiographic evidence of continuity of the coronary sinuses had identical heart rates on ECG. Both had broad, polyphasic QRS complexes, and various imaging modalities were unable to determine whether there was ventricular myocardial continuity. Administration of adenosine demonstrated that the broad polyphasic complexes were a "fusion" of the twins' individual QRS complexes, which could be clearly distinguished after administration of the drug. Ventricular pacing resulted in dissociation of the individual QRS complexes, thus demonstrating an absence of ventricular myocardial continuity. This was confirmed when the twins were successfully separated at the age of 10 months.     

一对糖尿病双生子肾虚证动态变化观察

目的:以病证结合的方法调查一对2型糖尿病(Type 2 Diabetes Mellitus,T2DM)双生子,分析双生子肾虚证随病程延长的动态变化特征。方法连续2年每年5次评估双生子病情,采用包含39项症状指标的肾虚证量表对双生子各临床症状逐项进行四级评分。结果:大双和小双的肾虚程度均随病程延长而逐渐加重,但是加剧的程度不一致,小双重于大双。肾虚证细化分型可见二者都辨为肾阴阳两虚证,随病程递增,以肾阴虚程度加重更为突出,小双的这种表现更明显。讨论:同卵双生子由于遗传物质完全相同,双生子间表现出西医病和中医证的属性也基本相同。但是由于个体差异、外在环境等的影响,二者在病情程度和发病进程上有明显的差异。