Using monozygotic twin differences to examine the relationship between parental affection and personality: a life history account

The relationship between maternal and paternal affection, reported in adulthood, and personality was examined using a genetically sensitive research design comparing differences between monozygotic twins. Using life history theory as a framework, it was predicted that differences in maternal and paternal affection would be predictive of differences in personality such that the twin reporting greater maternal and paternal affection would also report a personality profile reflective of a slow life history strategy. Specifically, it was predicted that the twin that reported greater maternal and paternal affection would also score high on the meta-traits of plasticity, stability, and the general factor of personality (GFP). The results supported the hypotheses, with most variance accounted for by the GFP. Additional results suggest that differences in paternal affection exhibit a stronger effect and that stability and plasticity may provide unique information about the association between differences in parental affection and differences in personality. Attachment and parental investment theories offer possible explanations for the findings, although alternative explanations are also proffered. It may also be beneficial for future research using a monozygotic twin difference approach to utilize biometric measures of life history strategy.     

Social learning of diet and foraging skills by wild immature Bornean orangutans: implications for culture

Studies of social learning in the wild are important to complement findings from experiments in captivity. In this field study, immature Bornean orangutans rarely foraged independently but consistently followed their mothers' choices. Their diets were essentially identical to their mothers' even though not all mothers had the same diet. This suggests vertical transmission of diet by enhancement. Also, immatures selectively observed their mothers during extractive foraging, which increased goal‐directed practice but not general manipulation of similar objects, suggesting observational forms of learning of complex skills. Teaching was not observed. These results are consistent with the reported presence of food traditions and skill cultures in wild orangutans. We suggest that food traditions can develop wherever association commonly allows for social learning. However, the capacity for observational learning, and thus more complex culture, is more likely to evolve among extractive foragers with prolonged association between adults and immatures. Am. J. Primatol. 72:62–71, 2010. © 2009 Wiley‐Liss, Inc.     

Polymorphic Cytochrome P450 Enzymes (CYPs) and Their Role in Personalized Therapy

The cytochrome P450 (CYP) enzymes are major players in drug metabolism. More than 2,000 mutations have been described, and certain single nucleotide polymorphisms (SNPs) have been shown to have a large impact on CYP activity. Therefore, CYPs play an important role in inter-individual drug response and their genetic variability should be factored into personalized medicine. To identify the most relevant polymorphisms in human CYPs, a text mining approach was used. We investigated their frequencies in different ethnic groups, the number of drugs that are metabolized by each CYP, the impact of CYP SNPs, as well as CYP expression patterns in different tissues. The most important polymorphic CYPs were found to be 1A2, 2D6, 2C9 and 2C19. Thirty-four common allele variants in Caucasians led to altered enzyme activity. To compare the relevant Caucasian SNPs with those of other ethnicities a search in 1,000 individual genomes was undertaken. We found 199 non-synonymous SNPs with frequencies over one percent in the 1,000 genomes, many of them not described so far. With knowledge of frequent mutations and their impact on CYP activities, it may be possible to predict patient response to certain drugs, as well as adverse side effects. With improved availability of genotyping, our data may provide a resource for an understanding of the effects of specific SNPs in CYPs, enabling the selection of a more personalized treatment regimen.     

Combined,Sequential Intravenous and Intra-Arterial Chemotherapy (Bridge Chemotherapy) for Young Infants with Retinoblastoma

Background

Intra-arterial (IA) chemotherapy has more risks of procedural complications in neonates and young infants. For these reasons, we have developed a strategy of bridge intravenous single agent chemotherapy to postpone IA chemotherapy in these children

Procedure

Neonates and young infants with retinoblastoma who required chemotherapy were treated with systemic carboplatin chemotherapy (18.7 mg/kg IV every 3–4 weeks) until they reached the age of 3 months and a weight of 6 Kg. If necessary, IA chemotherapy was subsequently performed at 4 weeks intervals. Efficacy was judged by tumor regression on ophthalmological examination. Retinal toxicity was judged by electroretinography.

Results

Eleven children (19 eyes) were treated. All patients are alive and no patient has developed metastatic disease or second malignancies (mean follow-up 27 months, range 9–46 months). Intravenous carboplatin (median 2 cycles, range 1–5) combined with cryotherapy and laser was given to all children. This was effective for five eyes, which did not require IA chemotherapy. IA chemotherapy was administered to 14 eyes (median 3.5 cycles per eye, range 1 to 6). No radiation therapy was required. The Kaplan Meier estimate of ocular radiation-free survival was 94.7% at one year (95% confidence interval 68.1–99.2%). One eye was enucleated due to tumor progression. ERG showed no deterioration of retinal function.

Conclusion

Bridge IV-IA chemotherapy was feasible and safe, and is a promising strategy to treat retinoblastoma in neonates and young infants.     

Clinical aspects of male germ cell apoptosis during testis development and spermatogenesis

Apoptosis appears to have an essential role in the control of germ cell number in testes. During spermatogenesis germ cell deletion has been estimated to result in the loss of up to 75% of the potential number of mature sperm cells. At least three factors seem to determine the onset of apoptosis in male germ cells: (1) lack of hormones, especially gonadotropins and androgens; (2) the specific stage in the spermatogenic cycle; (3) and the developmental stage of the animal. Although male germ cell apoptosis has been well characterized in various animal models, few studies are presently available regarding germ cell apoptosis in the human testis. The first part of this review is focused on germ cell apoptosis in testes of prepubertal boys, with special emphasis on apoptosis in normal and cryptorchid testes. A higher percentage of apoptotic spermatogonia was seen in the cryptorchid testes than in the scrotal testes. The hCG-treatment increased the number of apoptotic spermatogonia. The hCG-treatment-induced apoptosis in spermatogonia had severe long-term consequences in reproductive functions in adulthood. Increased apoptosis after hCG-treatment was associated with subnormal testis volumes, subnormal sperm density and pathologically elevated serum FSH. This finding indicates that increased apoptosis in spermatogonia in prepuberty leads to disruption of testis development. To evaluate the role of apoptosis in human adult testes, apoptosis was induced in seminiferous tubules that were incubated under serum-free conditions in the absence or presence of testosterone. Most frequently apoptosis was identified in spermatocytes. Occasionally some spermatids also showed signs of apoptosis. In short term incubations apoptosis was suppressed by testosterone. Our findings lead to the conclusion that apoptosis is a normal, hormonally controlled phenomenon in the human testis. The role of apoptosis in disorders of spermatogenesis remains to be established.     

Pre- and postsynaptic mechanisms in the clonidine- and oxymetazoline-induced inhibition of gastric motility in the rat

The inhibitory effect of clonidine (non-selective alpha2-adrenoceptor agonist) and oxymetazoline (alpha2A-adrenoceptor selective agonist) was compared on basal and stimulated gastric motor activity (gastric tone and contractions) using the balloon method in the rat. It was shown that oxymetazoline (0.2-1.7 micromol/kg, i.v.) decreased the basal motility, while clonidine (1.9-3.8 micromol/kg, i.v.) failed to affect it. When motility was stimulated centrally by insulin (5 IU/rat, i.v.), both clonidine (1.9-3.8 micromol/kg, i.v.) and oxymetazoline (0.1-3.4 micromol/kg, i.v.) inhibited the gastric motor activity. However, while the effect of clonidine was antagonized by the non-selective alpha2-adrenoceptor antagonist yohimbine (5 micromol/kg, i.v.) and the alpha2A-adrenoceptor selective antagonist BRL 44408 (3 micromol/kg, i.v.), the effect of oxymetazoline was only partially affected. Prazosin (alpha1- and alpha2B-adrenoceptor antagonist, 0.07-0.28 micromol/kg, i.v.) also failed to reverse the effect of oxymetazoline. Furthermore, when gastric motility was stimulated peripherally by activation of postsynaptic cholinergic muscarinic receptors by the combination of carbachol (0.14 micromol/kg, i.v.) and hexamethonium (37 micromol/kg, i.v.), clonidine (3.8 micromol/kg, i.v.) failed to affect the increased motor activity, however, oxymetazoline (0.8-3.4 micromol/kg, i.v.) exerted a pronounced inhibition. These results suggest that different mechanisms may be involved in the inhibitory effect of clonidine and oxymetazoline; while clonidine reduces the gastric motility by activation of presynaptic alpha2-adrenoceptors, postsynaptic component in the effect of oxymetazoline has also been raised.     

Ophthalmic artery chemosurgery for less advanced intraocular retinoblastoma: five year review

Background

Ophthalmic artery chemosurgery (OAC) for retinoblastoma was introduced by us 5 years ago for advanced intraocular retinoblastoma. Because the success was higher than with existing alternatives and systemic side effects limited we have now treated less advanced intraocular retinoblastoma (Reese-Ellsworth (RE) I-III and International Classification Retinoblastoma (ICRB) B and C).

Methodology/Principal Findings

Retrospective review of 5 year experience in eyes with Reese Ellsworth (