Fingerprint recognition with identical twin fingerprints

Fingerprint recognition with identical twins is a challenging task due to the closest genetics-based relationship existing in the identical twins. Several pioneers have analyzed the similarity between twins' fingerprints. In this work we continue to investigate the topic of the similarity of identical twin fingerprints. Our study was tested based on a large identical twin fingerprint database that contains 83 twin pairs, 4 fingers per individual and six impressions per finger: 3984 (83*2*4*6) images. Compared to the previous work, our contributions are summarized as follows: (1) Two state-of-the-art fingerprint identification methods: P071 and VeriFinger 6.1 were used, rather than one fingerprint identification method in previous studies. (2) Six impressions per finger were captured, rather than just one impression, which makes the genuine distribution of matching scores more realistic. (3) A larger sample (83 pairs) was collected. (4) A novel statistical analysis, which aims at showing the probability distribution of the fingerprint types for the corresponding fingers of identical twins which have same fingerprint type, has been conducted. (5) A novel analysis, which aims at showing which finger from identical twins has higher probability of having same fingerprint type, has been conducted. Our results showed that: (a) A state-of-the-art automatic fingerprint verification system can distinguish identical twins without drastic degradation in performance. (b) The chance that the fingerprints have the same type from identical twins is 0.7440, comparing to 0.3215 from non-identical twins. (c) For the corresponding fingers of identical twins which have same fingerprint type, the probability distribution of five major fingerprint types is similar to the probability distribution for all the fingers' fingerprint type. (d) For each of four fingers of identical twins, the probability of having same fingerprint type is similar.     

Paroxysmal nocturnal hemoglobinuria in an identical twin

The presentation of symptoms, laboratory findings and possible precipitating factors are reviewed in an 18-year-old patient with the onset of typical paroxysmal nocturnal hemoglobinuria. The opportunity was taken to study the physiology in his normal identical twin sibling who showed no hematological abnormalities on exhaustive studies, including photoscanning of the erythrocytes. These observations strengthen the evidence that PNH is an acquired disease with no basic measurable abnormalities of a hereditary or genetic nature.     

Heritability of running economy: a study made on twin brothers

Running economy (RE), defined as the steady-state of oxygen uptake (V˙O₂) for a given running velocity, is a factor of sports performance the genetic component of which has seldom been reported to date. We studied this component using a heritability index (HI) in a group of 32 male twins, 8 monozygotic (MZ) and 8 dizygotic (DZ) pairs, all sportsmen with similar perinatal and environmental backgrounds. Zygocity was determined by the identity of erythrocytic antigenic, protein and enzymatic polymorphism, and human leucocyte antigen serologic types between co-twins. The subjects exercised twice on a treadmill, once until exhaustion and again at submaximal intensities. Pulmonary gas exchange was measured continuously using an automatic analyser system during both tests. Blood samples were obtained during the recovery period to determine lactate concentrations. No significant differences were observed between MZ and DZ, in respect of RE at any speed or in maximal V˙O₂ relative to body mass. Nevertheless, significant HI (P < 0.05) was found in maximal lactate concentrations (HI = 0.75) and in respiratory equivalent for oxygen at two speeds, 7 km · h⁻¹ (HI = 0.71) and 8 km · h⁻¹ (HI = 0.79), differences which probably suggest that there are differences in RE. In conclusion, we did not detect a genetic component in RE or in maximal oxygen uptake, but a genetic component for markers of anaerobic metabolism was present. Accepted: 5 November 1997     

Production of identical twin rabbits by micromanipulation of embryos

The research was conducted to improve micromanipulation procedures with rabbit embryos, including the production of genetically identical progeny. In the first experiment, embryos in different stages of development were used for micromanipulation by removing half of the blastomeres with a beveled aspirating pipette. Embryos 74-78 h postovulatory, in the late compacted morula or early blastocyst stage, were demonstrated to be best for micromanipulation. When embryos at this stage were halved, 77% (64/83) developed into blastocysts compared to 78% (65/83) for the intact control. In the second experiment, the survival of demi-embryos in original versus foreign zonae was tested. Young born from the demi-embryos transferred within original zonae (33%) were not significantly different (p greater than 0.05) from those transferred in foreign zonae (24%). Significantly more offspring, however, were obtained from intact control embryos (58%, p less than 0.01). In the third experiment, identical monozygotic twins were produced from Day 3 embryos, after modification of the aspirating pipette by further sharpening it to a fine point with a microforge. Thirty-four percent young (11) were obtained after microsurgery compared to 36% for intact control embryos transferred. Among the demi-embryos, a pair of albino and a pair of Dutch-belted young were identical twins.     

Production of identical twin and triplet mice by nuclear transplantation

Transplantation of a single nucleus from two- or four-cell embryos into one of the enucleated blastomeres of a two-cell embryo resulted in successful production of identical triplet and twin mice. The proportion of reconstituted embryos that developed in blastocysts was 71% (84/118) when four-cell embryos were used as donors of nuclei; 10 sets of quadruplet and nine sets each of triplet and twin blastocysts were obtained by this technique. After transfer to recipients, 30% (18/61) developed to term, and one set of identical triplet and four sets of identical twin mice were obtained. When two-cell embryos were used as donors of nuclei, 79 (95%) sets of twin embryos developed to blastocysts. Of 38 twin blastocysts transferred to recipients, 21 sets (55%) developed to term as identical twin mice. These results demonstrate that the enucleated two-cell embryo develops in vitro after transfer of a nucleus from a two- or four-cell embryo and the resultant blastocyst has high potential for development to term after transfer to a recipient.     

Erythrocyte sodium-lithium countertransport and blood pressure in identical twin pairs discordant for insulin dependent diabetes.

OBJECTIVE--To investigate whether insulin dependent diabetes is responsible for the abnormal behaviour of the carrier in sodium-lithium countertransport and whether the diabetic state is associated with rise in blood pressure. DESIGN--Case-control study. SETTING--London teaching hospital. SUBJECTS--44 twin pairs discordant for insulin dependent diabetes living in United Kingdom and 44 healthy control subjects matched for age, sex, and body mass index. None of the twin pairs or the controls had evidence of microalbuminuria. MAIN OUTCOME MEASURES--Sodium-lithium countertransport activity in erythrocytes and arterial blood pressure. RESULTS--The mean (95% confidence interval) sodium-lithium countertransport activity (mmol Li per litre of red blood cells per h) of the diabetic twins (0.291 (0.244 to 0.338)) was similar to that of their non-diabetic cotwins (0.247 (0.204 to 0.290)); both values were significantly higher than that of the controls (0.187 (0.157 to 0.216); p < 0.05). In addition, systolic blood pressure was higher in those twins with diabetes (127 (122 to 133) mm Hg) than in the non-diabetic cotwins (122 (117 to 127) mm Hg; p < 0.01). There were no significant differences in mean diastolic blood pressure between any of the groups studied. CONCLUSIONS--The raised erythrocyte sodium-lithium countertransport activity in the diabetic twins compared with the controls seems to be inherited rather than a consequence of overt diabetes. The higher systolic blood pressure in diabetic twins than non-diabetic cotwins indicates that insulin dependent diabetes does exert a small influence on systolic blood pressure.     

An analysis of seven infants with Brachmann-de Lange syndrome, of whom two identical twin sisters

An analysis of seven infants with Brachmann-de Lange syndrome, of whom two identical twin sisters: Brachmann-de Lange syndrome (BDLS) is characterized by typical facial features, intrauterine growth retardation, short stature, microbrachycephaly, hirsutism and limb anomalies. Here, we reviewed the findings of seven infants with BDLS, of whom two were identical twin sisters of normal parents. All of the infants' parents were normal, and no consanguinity between the parents was noted although the ratio of consanguineous marriages is very high (21.1%) in Turkey. It is well known that most cases of BDLS are sporadic, some cases of this disorder are inherited in an autosomal dominant trait. Our findings suggested that familial cases of BDLS were infrequent, and vast majority of cases appeared to be sporadic and the occurrence of the syndrome in the identical twin sisters of normal parents was also thought a heterogeneity in this condition, overlapping with other conditions and syndromes as mentioned by Fryns et al.     

Drosophila twin spot clones reveal cell division dynamics in regenerating imaginal discs

Cell proliferation is required for tissue regeneration, yet the dynamics of proliferation during regeneration are not well understood. Here we investigated the proliferation of eye and leg regeneration in fragments of Drosophila imaginal discs. Using twin spot clones, we followed the proliferation and fates of sister cells arising from the same mother cell in the regeneration blastema. We show that the mother cell gives rise to two sisters that participate equally in regeneration. However, when cells switch disc identity and transdetermine to another fate, they fail to turn off the cell cycle and continue dividing long after regeneration is complete. We further demonstrate that the regeneration blastema moves as a sweep of proliferation, in which cells are displaced. Our results suggest that regenerating cells stop dividing once the missing parts are formed, but if they undergo a switch in cell fate, the proliferation clock is reset.     

The Ubi brothers reunited

Atg12 and Atg8/LC3 are two ubiquitin-like proteins involved in autophagosome formation. They show several similar characteristics just like brothers evolved from the same ancestor, however, their functional relationship has been obscure. We recently reported that a super protein complex, the Atg16L complex, which consists of multiple Atg12-Atg5 conjugates and the associating protein Atg16L, has an E3-like role in the LC3 lipidation reaction(1). The activated intermediate, LC3-Atg3 (E2) is recruited to the site where the lipidation takes place by virtue of the Atg16L complex. Thus, these two closely resembling systems are connected also in terms of their functions. This finding will provide further important clues as to the origin of the autophagosome membrane, and how the process is regulated by starvation and PtdIns3P signals.     

Cancer metabolism and the dynamics of metastasis

Cancer growth dynamics, commonly simulated with a Gompertzian model, is analyzed in the framework of a more recent and realistic model. In particular, we consider the setting of a tumor embedded in a host organ and investigate their interaction. We assume that, at least in some cases, tumor metastasis may be triggered by an ‘energetic crisis’, when the tumor exceeds the ‘carrying capacity’ of the host organ. As a consequence, dissemination of clusters of cancer cells is set in motion, with a statistical probability given by a Poisson distribution. The model, although still at a preclinical level, is fully quantitative and is applied, as an example, to the case of prostate cancer. The results confirm that, at least for the more aggressive cancers, metastasis starts very early during tumorigenesis and a quantitative link is found between the tumor's doubling time, its ‘aggressiveness’ and the metastatic potential.     

The presence of both stochastic and deterministic dynamics in electroretinograms measured under identical experimental conditions

We have studied whether living things investigated under the same measuring conditions can generate signals with different types of dynamics. We also wanted to detect the possible effects of low-intensity microwaves using parameters of deterministic chaos. For this purpose, two sets of electroretinograms were analysed by methods aimed at recognizing different types of dynamics. Both sets included the time series recorded from objects exposed to low-intensity microwaves and those that were not exposed. The analytical methods are based on nonlinear forecasting and a “surrogate data” technique. Although the experimental conditions were identical for the two sets, we have shown that both have time series with deterministic and stochastic dynamics. We also found that the use of parameters of deterministic dynamics is insufficient to distinguish between the sets. Received: 18 January 1994 / Accepted: 13 June 1997