Single-neuron sequencing analysis of L1 retrotransposition and somatic mutation in the human brain.

A major unanswered question in neuroscience is whether there exists genomic variability between individual neurons of the brain, contributing to functional diversity or to an unexplained burden of neurological disease. To address this question, we developed a method to amplify genomes of single neurons from human brains. Because recent reports suggest frequent LINE-1 (L1) retrotransposition in human brains, we performed genome-wide L1 insertion profiling of 300 single neurons from cerebral cortex and caudate nucleus of three normal individuals, recovering >80% of germline insertions from single neurons. While we find somatic L1 insertions, we estimate <0.6 unique somatic insertions per neuron, and most neurons lack detectable somatic insertions, suggesting that L1 is not a major generator of neuronal diversity in cortex and caudate. We then genotyped single cortical cells to characterize the mosaicism of a somatic AKT3 mutation identified in a child with hemimegalencephaly. Single-neuron sequencing allows systematic assessment of genomic diversity in the human brain.

Isomeric Character of the Lowest Observed 4

Previous experiments observed a 4^{+} state in the N=28 nucleus ^{44}S and suggested that this state may exhibit a hindered E2-decay rate, inconsistent with being a member of the collective ground state band. We populate this state via two-proton knockout from a beam of exotic ^{46}Ar projectiles and measure its lifetime using the recoil distance method with the GRETINA γ-ray spectrometer. The result, 76(14)_{stat}(20)_{syst} ps, implies a hindered transition of B(E2;4^{+}→2_{1}^{+})=0.61(19) single-particle or Weisskopf units strength and supports the interpretation of the 4^{+} state as a K=4 isomer, the first example of a high-K isomer in a nucleus of such low mass.

Barriers to contraceptive use among adolescents in two semi-rural Nicaraguan communities.

Objective To identify barriers to contraceptive use among adolescents in two neighboring semi-rural communities in Nicaragua. Methods We recruited and surveyed a convenience sample of 287 adolescents, ages 15-19 years old, in July and August, 2013 about barriers to contraceptive use. We compared adolescents by gender, sexually active status (sexual intercourse in the previous year) and frequency of contraceptive use. Results More than 40% (43.5%) of the adolescents surveyed reported that they had ever had sexual intercourse. The likelihood of ever having had sexual intercourse differed based on gender, relationship status, sexual activity of peers, and the presence of a father in the home. Contraceptive use was low and female adolescents were more likely than their male counterparts to report never or rarely using contraceptives (46.5% vs. 21.4%, p < 0.007). Contraceptive use for females was positively associated with discussing contraception with a healthcare professional (HCP) [adjusted odds ratio (AOR) 13.32; 95% confidence interval (CI) 1.35-139.98] and a family member (AOR 4.64; 95% CI 1.09-19.72). Reasons for non-use also varied significantly by gender. Low rates of contraceptive use in these two semi-rural Nicaraguan communities appear to be primarily related to gender norms, social stigma, and poor communication about family planning. Conclusions Interventions that focus on promoting gender equality and encouraging adolescent communication with HCPs, schools, families, and partners are imperative to combating adolescent pregnancy in Nicaragua and countries worldwide.

Quantification of Nitrosomonas oligotropha and Nitrospira spp. using competitive polymerase chain reaction in bench-scale wastewater treatment reactors operating at different solids retention times.

The effect of solids retention time (SRT) on ammonia-and nitrite-oxidizing bacteria was measured by Nitrosomonas oligotropha-like ammonia monooxygenase A and Nitrospira 16S rDNA competitive polymerase chain reaction assays in a complete-mix, bench-scale, activated-sludge system. During steady-state operation, nitrification was complete in the 20- and 10-day SRT reactors, nearly complete in the 5-day SRT reactor, and incomplete in the 2-day SRT reactor (76% ammonia oxidation and 85% nitrite oxidation). Total microbes, measured by dot-blot hybridizations, ranged from 3 x 10(11) to 3 x 10(12) cells/L, and increased with increasing SRTs. The concentration of the ammonia-oxidizer N. oligotropha dropped 100-fold from the 20-day SRT (5 x 10(9) cells/L) to the 2-day SRT (< or = 4 x 10(7) cells/L). Thus, N. oligotropha became a much smaller fraction of the total biomass in the poorly performing 2-day SRT reactor. The concentration of Nitrospira cells also decreased (10-fold) as the SRT was reduced from 20 days to 2 days. However, the number of Nitrospira cells was always greater than the number of N. oligotropha cells measured in each reactor (10- to 60-fold). While Nitrospira comprised 1 to 2% of the biomass, N. oligotropha represented only 0.04 to 0.27% of the total population. This low percentage suggests that N. oligotropha was not a dominant ammonia oxidizer in the bench-scale systems.

Preventive services in a hybrid capitation and fee-for-service setting.

The potential omission of indicated tests for patients enrolled in prepaid health care plans has been raised as a possibility. This study reviewed the charts of 149 adult patients seen for routine physical examinations or checkups in university-based family medicine or internal medicine clinics. Of the patients included, 67 were enrolled in a capitated plan and 82 enrolled in fee-for-service based plans. Results showed that the rates of compliance with preventive services appropriate to patients' age and sex (Papanicolaou smears, breast examination, mammography, and stool examination for occult blood) were not significantly different for capitated and fee-for-service patients.

Radiographic diagnosis of intestinal perforation in early infancy.

Records of 25 patients with intestinal perforation in early infancy who were treated at the Los Angeles County General Hospital in a period of 15 years were reviewed. Sixteen had roentgen evidence of pneumoperitoneum, and nine did not. The mortality rate was 94 per cent in the group with pneumoperitoneum, 78 per cent in the other, and 88 per cent overall. Multiple sites in the gastrointestinal tract were involved, and the causes of the lesions were diverse and frequently obscure. Prematurity, obstetrical and iatrogenic complications, and congenital anomalies were factors often associated with intestinal perforation. Roentgen features appeared to offer the best hope for diagnosis and appropriate treatment.

Diagnosis of Caroli disease by computed tomography: report of two cases.

Two patients are discussed in whom Caroli diseases was diagnosed with the aid of computed tomography (CT). One patient had the pure form of the disease, characterized primarily by saccular dilatation of the intrahepatic bile ducts and clinically manifesting as recurrent cholangitis. The second patient had a form ccharacterized primarily by hepatic fibrosis and clinically manifesting as portal hypertension. These are the first patients studied with CT to be reported to the authors' knowledge; CT is recommended as the optimal noninvasive method to evaluate such patients.