Entangled States and Collective Nonclassical Effects in Two-Atom Systems

We propose a review of recent developments on entanglement and nonclassical effects in collective two-atom systems and present a uniform physical picture of the many predicted phenomena. The collective effects have brought into sharp focus some of the most basic features of quantum theory, such as nonclassical states of light and entangled states of multiatom systems. The entangled states are linear superpositions of the internal states of the system which cannot be separated into product states of the individual atoms. This property is recognized as entirely quantum-mechanical effect and have played a crucial role in many discussions of the nature of quantum measurements and, in particular, in the developments of quantum communications. Much of the fundamental interest in entangled states is connected with its practical application ranging from quantum computation, information processing, cryptography, and interferometry to atomic spectroscopy.

Squeezing-induced complete transparency in two-level systems

The modification of the statistical properties of vacuum fluctuations, via quadrature squeezing, can dramatically reduce the absorptive and dispersive properties of two-level atoms. We show that for some range of parameter values the system exhibits zero absorption accompanied by zero dispersion of the probe field. This complete transparency is attributed to the coherent population oscillations induced by the squeezed vacuum.

Purification,characterization and crystallization in two crystal forms of bovine cyclophilin 40

The purification and crystallization of two different crystal forms of the two-domain protein bovine cyclophilin 40 is reported. Tetragonal crystals grown in methyl pentanediol belong to space group P4(2)22 with unit-cell parameters a = 94.5, c = 118.3 Angstrom. Long thin needles grown from PEG belong to space group C2 with unit-cell parameters a = 125.71, b = 47.3, c = 74.6 Angstrom, beta = 93.90 degrees. The N-terminal 170 amino acids have significant homology with the well characterized human cyclophilin A. The C-terminal domain is largely made up of three copies of the tetratricopeptide repeat motif thought to be involved in mediating protein-protein interactions. Cyclophilins are frequently found as domains in larger multidomain proteins. To date, only X-ray structures of single-domain cyclophilins have been reported, and this work provides the first example of the purification and crystallization of a larger protein containing a cyclophilin domain.

Transient evoked otoacoustic emissions in two-month-old infants: A normative study

Researchers have recently reported the effects of age, sex, ear asymmetry, and subject's activity status on transient evoked otoacoustic emissions (TEOAEs). The present study aimed to expand upon such reports by describing the characteristics of TEOAE spectra obtained from a cohort of 607 two-month-old infants in community child health clinics. Results indicated significant sex, ear and activity state effects on the signal:noise ratio, response. whole wave and band reproducibility values. These findings suggest the need for TEOAE normative data to be expressed as a function of sex, ear, and activity state of infants. These characteristics of TEOAE spectra may shape future investigations into appropriate pass-fail criteria for two-month-old infants.

Variable expression of mental retardation, autism, seizures, and dystonic hand movements in two families with an identical ARX gene mutation

Two families, originally diagnosed as having nonsyndromic X-linked mental retardation (NSXLMR), were reviewed when it was shown that they had a 24-bp duplication (428-45 1dup(24bp)) in the ARX gene [Stromme et al., 2002: Nat Genet 30:441-445]. This same duplication had also been found in three other families: one with X-linked infantile spasms and hypsarrhythmia (X-linked West syndrome, MIM 308350) and two with XLMR and dystonic movements of the hands (Partington syndrome, MIM 309510). On review, manifestations of both West and Partington syndromes were found in some individuals from both families. In addition, it was found that one individual had autism and two had autistic behavior, one of whom had epilepsy. The degree of mental retardation ranged from mild to severe. A GCG trinucleotide expansion (GCG)10+7 and a deletion of 1,517 by in the ARX gene have also been found in association with the West syndrome, and a missense mutation (1058C >T) in a family with a newly recognized form of myoclonic epilepsy, severe mental retardation, and spastic paraplegia [Scheffer et al., 2002: Neurology, in press]. Evidently all these disorders are expressions of mutations in the same gene. It remains to be seen what proportions of patients with infantile spasms, focal dystonia, autism, epilepsy, and nonsyndromic mental retardation are accounted for by mutations in the ARX gene. (C) 2002 Wiley-Liss, Inc.

Comparative analysis of population structure of endemic Western Atlantic hermit crab Loxopagurus loxochelis (Decapoda, Anomura) in two regions of state of Sao Paulo, Brazil

This work characterized the population structure of the hermit crab Loxopagurus loxochelis (Moreira, 1901) in terms of size frequency distribution and sex ratio. Specimens were collected monthly, over a period of one year (from July 2002 to June 2003), in seven transects (from 5 to 35 m of depth) using fishing boat equipped with two double-rig trawl nets, in Caraguatatuba and Ubatuba regions (state of Sao Paulo, Brazil). A total of 366 hermit crabs were collected in Caraguatatuba [222 males (60.65%), 114 non-ovigerous females (31.15%) and 30 ovigerous females (8.20%)] and 126 hermit crabs in Ubatuba [81 males (64.28%), 38 non-ovigerous females (30.16%) and seven ovigerous females (5.56%)]. In Caraguatatuba the highest incidence of ovigerous females occurred during winter (July 2002), whereas in Ubatuba, the number was incipient. The cephalothoracic shield length ranged from 2.0 to 7.9mm (5.29 +/- 0.96mm) in Caraguatatuba, and from 2.7 to 7.5mm (5.32 +/- 0.95mm) in Ubatuba. The mean size of males was significantly larger than the mean size of females in both regions. Overall sex ratio was in favor of males (1.54:1 in Caraguatatuba and 1.9:1 in Ubatuba). Sexual dimorphism was recorded to L. loxochelis by the presence of males in the largest size classes, following the standard pattern observed in Decapoda. There was an unimodal size distribution for both sexes, with normal distributions in both regions. The higher number of males in relation to females may indicate the existence of different growth and mortality rates between the sexes. Despite of the different geomorphologic characteristics between Caraguatatuba and Ubatuba regions, the dynamics of development was similar for both populations.

Prostatic Artery Embolization as a Primary Treatment for Benign Prostatic Hyperplasia: Preliminary Results in Two Patients

Symptomatic benign prostatic hyperplasia (BPH) typically occurs in the sixth and seventh decades, and the most frequent obstructive urinary symptoms are hesitancy, decreased urinary stream, sensation of incomplete emptying, nocturia, frequency, and urgency. Various medications, specifically 5-alpha-reductase inhibitors and selective alpha-blockers, can decrease the severity of the symptoms secondary to BPH, but prostatectomy is still considered to be the traditional method of management. We report the preliminary results for two patients with acute urinary retention due to BPH, successfully treated by prostate artery embolization (PAE). The patients were investigated using the International Prostate Symptom Score, by digital rectal examination, urodynamic testing, prostate biopsy, transrectal ultrasound (US), and magnetic resonance imaging (MRI). Uroflowmetry and postvoid residual urine volume complemented the investigation at 30, 90, and 180 days after PAE. The procedure was performed under local anesthesia; embolization of the prostate arteries was performed with a microcatheter and 300- to 500-mu m microspheres using complete stasis as the end point. One patient was subjected to bilateral PAE and the other to unilateral PAE; they urinated spontaneously after removal of the urethral catheter, 15 and 10 days after the procedure, respectively. At 6-month follow-up, US and MRI revealed a prostate reduction of 39.7% and 47.8%, respectively, for the bilateral PAE and 25.5 and 27.8%, respectively, for the patient submitted to unilateral PAE. The early results, at 6-month follow-up, for the two patients with BPH show a promising potential alternative for treatment with PAE.

DISCORDANCE FOR RETINITIS PIGMENTOSA IN TWO MONOZYGOTIC TWIN PAIRS

Background: Retinitis pigmentosa (RP) is a group of genetically heterogeneous diseases with progressive degeneration of the retina. The condition can be inherited as an autosomal dominant, autosomal recessive, and X-linked trait. Methods: We report on two female twin pairs. One twin of each pair is affected with RP, the other twin is unaffected, both clinically and functionally. Molecular analysis in both twins included zygosity determination, arrayed primer extension chip analysis for autosomal recessive and dominant RP, sequencing of the entire RPGR gene, and analysis of X-chromosome inactivation status. Results: Both unrelated twin pairs were genetically identical. Of the potential pathogenetic mechanisms, skewed X-inactivation was excluded on leukocytes. Autosomal recessive RP and autosomal dominant RP arrayed primer extension chip analysis result was completely normal, excluding known mutations in known genes as the cause of disease in the affected twins. Sequencing excluded mutations in RPGR. A postzygotic recessive or dominant genetic mutation of an RP gene is not impossible. A postfertilization error as a potential cause of uniparental isodisomy is unlikely albeit not entirely impossible. Conclusion: The authors report on the second and third unrelated identical twin pair discordant for RP. The exact cause of the condition and the explanation of the clinical discordance remain elusive. RETINA 31:1164-1169, 2011

Age-dependent increase in blood pressure in two different Native American communities in Brazil

Objective Cardiovascular risk factors were surveyed in two Indian populations (Guarani, n=60; Tupinikin, n=496) and in a non-Indian group (n=114) living in the same reserve in southeast Brazilian coast. The relationship between an age-dependent blood pressure (BP) increase with salt consumption was also investigated. Methods Overnight (12 h) urine was collected to evaluate Na excretion. Fasting glucose and lipids, anthropometry, BP, ECG and carotid-femoral pulse wave velocity (PWV) were measured in a clinic visit. Participation (318 men/352 women, age 20-94 years; mean=37.6 +/- 14.9 years) comprised 80% of the eligible population. Results The prevalence of hypertension, diabetes and high cholesterol was similar in Tupinikins and in non-Indians and higher than in Guaranis. The prevalence of smoking and obesity was higher in the latter group. Hypertension and diabetes were detected in only one individual of the Guarani group. Mean BP adjusted to age and BMI was significantly lower (P<0.01) in Guaranis (82.8 +/- 1.6 mmHg) than in Tupinikins (92.3 +/- 0.5 mmHg) and non-Indians (91.6 +/- 1.1 mmHg). Urinary Na excretion (mEq/12h), however, was similar in the three groups (Guarani=94 +/- 40; Tupinikin=105 +/- 56; non-Indian=109 +/- 55; P>0.05). PWV (m/s) was lower (P<0.01) in Guarani (7.5 +/- 1.4) than in Tupinikins (8.8 +/- 2.2) and non-Indians (8.4 +/- 2.0). Multiple regression analysis showed that age and waist-to-hip ratio (WHR) were independent predictors of SBP and DBP (r(2)=0.44) in Tupinikins, whereas the WHR was the unique independent predictor of BP variability in Guaranis (r(2)=0.22). Conclusion Lower BP levels in Guaranis cannot be explained by low salt intake observed in other primitive populations. J Hypertens 27:1753-1760 (C) 2009 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.

Dual candidemia detected by nested polymerase chain reaction in two critically ill children

The use of improved microbiological procedures associated with molecular techniques has increased the identification of Candida bloodstream infections, even if the isolation of more than one species by culture methods remains uncommon. We report the cases of two children presenting with severe gastrointestinal disorders and other risk factors that contribute to Candida infections. In the first patient, C. albicans DNA was initially detected by a nested-amplification and C. tropicalis was found later during hospitalization, while blood cultures were persistently negative. In the second child, there was amplification of C. albicans and C. glabrata DNA in the same samples, but blood cultures yielded only C. albicans. Both patients received antifungal therapy but had unfavorable outcomes. These two cases illustrate that PCR was more successful than culture methods in detecting Candida in the bloodstream of high risk children, and was also able to detect the presence of more than one species in the same patient that might impact therapy when the fungi are resistant to azole compounds.

A novel STAT5B mutation causing GH insensitivity syndrome associated with hyperprolactinemia and immune dysfunction in two male siblings

Background: GH insensitivity (GHI) syndrome caused by STAT5B mutations was recently reported, and it is characterized by extreme short stature and immune dysfunction. Treatment with recombinant human IGF1 (rhIGF1) is approved for patients with GHI, but the growth response to this therapy in patients with STAT5B mutations has not been reported. Objectives: To report the clinical features, molecular findings, and the short-term growth response to rhIGF1 therapy in patients with STAT5B mutation. Subjects and methods: Hormonal and immunological evaluations were performed in two male siblings with GHI associated with atopic eczema, interstitial lung disease, and thrombocytopenic purpura. STAT5B genes were directly sequenced. The younger sibling was treated with rhIGF1 at a dose of 110 mu g/kg BID. Results: Both siblings had laboratory findings compatible with GHI associated with hyperprolactinemia. Lymphopenia and reduced number of natural killer cells without immunoglobulin abnormalities were observed. STAT5B sequence revealed a homozygous frameshift mutation (p.L142fsX161) in both siblings. The younger sibling (9.9 years of age) was treated with rhIGF1 at appropriate dosage, and he did not present any significant change in his growth velocity (from 2.3 to 3.0 cm/year after 1.5 years of therapy). The presence of a chronic illness could possibly be responsible for the poor result of rhIGF1 treatment. Further studies in patients with STAT5B defects are necessary to define the response to rhIGF1 treatment in this disorder. Conclusion: GHI associated with immune dysfunction, especially interstitial lung disease, and hyperprolactinemia is strongly suggestive of a mutation in STAT5B in both sexes.

A novel homozygous splice acceptor site mutation of KISS1R in two siblings with normosmic isolated hypogonadotropic hypogonadism

Context: Loss-of-function mutations of the kisspeptin-1 receptor gene, KISS1R, have been identified in patients with normosmic isolated hypogonadotropic hypogonadism (nIHH). Objective: To investigate KISS1R defects in patients with absent or delayed puberty. Patients: We investigated KISS1R gene defects in a cohort of 99 Brazilian patients with nIHH or constitutional delay of puberty (CDP). Methods: The entire coding region of KISS1R was amplified by PCR followed by automatic sequencing. In addition, screening for KISS1R exonic deletions was performed by multiplex ligation-dependent probe amplification. Results: One novel homozygous KISS1R mutation was identified in two siblings with nIHH. This variant was an insertion/deletion (indel) mutation characterized by the deletion of three nucleotides (GCA) at position -2 to -4, and by the insertion of seven nucleotides (ACCGGCT) at the same position, within the 30 splice acceptor site of intron 2 of KISS1R. The brothers who carried this KISS1R mutation had no clinical evidence of pubertal development at the ages of 14 and 20 years. Computational analysis of this indel mutation predicted the generation of an abnormal protein. In addition, a new heterozygous KISS1R variant (p.E252Q) was identified in a male patient with sporadic nIHH. However, in vitro studies of this variant did not demonstrate functional impairment. Only known polymorphisms were identified in patients with CDP. Conclusion: Loss-of-function mutations of KISS1R represents a rare cause of nIHH, and was absent in patients with CDP. We have described a novel KISS1R homozygous splice acceptor site mutation in the familial form of nIHH.

Cigarette smoking and the incidence of Parkinson's disease in two prospective studies

An inverse association between cigarette smoking and idiopathic Parkinson's disease has been reported in several retrospective studies, but prospective evidence is available only for men. We assessed the association between the incidence of Parkinson's disease and smoking in two large prospective cohort studies comprising men and women. New cases of Parkinson's disease were identified in the Nurses' Health Study for 1976-1996, and in the Health Professionals Follow-up Study for 1986-1996. Smoking history was assessed at baseline and updated on subsequent biennial questionnaires. In women, the age-adjusted rate ratios (95% confidence intervals) for Parkinson's disease relative to never-smokers were 0.7 (0.5, 1.0) for past smokers, and 0.4 (0.2, 0.7) for current smokers. In men, the age-adjusted rate ratios for Parkinson's disease relative to never-smokers were 0.5 (0.4, 0.7) for past smokers, and 0.3 (0.1, 0.8) for current smokers. In both cohorts, the strength of the association decreased with time since quitting (among past smokers), increased with number of cigarettes per day (among current smokers), and increased with pack-years of smoking. These prospective findings confirm that an inverse association between smoking and the incidence of Parkinson's disease exists in both men and women.