Role of Primary Cilia in Odontogenesis.

Primary cilium is a solitary organelle that emanates from the surface of most postmitotic mammalian cells and serves as a sensory organelle, transmitting the mechanical and chemical cues to the cell. Primary cilia are key coordinators of various signaling pathways during development and maintenance of tissue homeostasis. The emerging evidence implicates primary cilia function in tooth development. Primary cilia are located in the dental epithelium and mesenchyme at early stages of tooth development and later during cell differentiation and production of hard tissues. The cilia are present when interactions between both the epithelium and mesenchyme are required for normal morphogenesis. As the primary cilium coordinates several signaling pathways essential for odontogenesis, ciliary defects can interrupt the latter process. Genetic or experimental alterations of cilia function lead to various developmental defects, including supernumerary or missing teeth, enamel and dentin hypoplasia, or teeth crowding. Moreover, dental phenotypes are observed in ciliopathies, including Bardet-Biedl syndrome, Ellis-van Creveld syndrome, Weyers acrofacial dysostosis, cranioectodermal dysplasia, and oral-facial-digital syndrome, altogether demonstrating that primary cilia play a critical role in regulation of both the early odontogenesis and later differentiation of hard tissue-producing cells. Here, we summarize the current evidence for the localization of primary cilia in dental tissues and the impact of disrupted cilia signaling on tooth development in ciliopathies.

Depressive symptoms are independently associated with pain perception in Colombians with rheumatoid arthritis.

AIMS: To examine the relationships between psychosocial factors and reported pain in Colombians with Rheumatoid Arthritis (RA). METHODS: One hundred and three RA patients [85% from the lowest socio-economic strata (SES) in the country] recruited from outpatient centers in Neiva, Colombia were administered the Disease Activity Scale (DAS) , which included a Visual Analog Scale (VAS) arthritis pain/activity rating, Zung Depression Scale, State-Trait Anxiety Inventory (STAI), Interpersonal Support Evaluation List-12 (ISEL-12), and Symptom Checklist-90 Revised (SCL-90R). MAJOR RESULTS: VAS pain was not associated with socio-demographic or medical factors, but was negatively associated with ISEL tangible subscale (r=-0.22, p< 0.01; r=0.28, p<0.01). VAS pain was positively associated with Zung Depression Scale score (r=0.38, p<0.001), STAI-State and STAI-Trait Anxiety (r=0.23 and r=0.25 respectively, p's<0.01), SCL-90R Global Severity Index (GSI) and Positive Symptom Total (PST) (r=0.23, p<0.05 and r=0.29, p<0.01 respectively), and SCL-90R Somatization, Depression, and Anxiety subscales (r=0.30, p< 0.01; r=0.28, p<0.01; and r=0.20, p<0.05 respectively). A linear regression model showed that socio-demographic characteristics theoretically associated with pain perception (gender, age, and SES) explained only 2.4% of the variance of VAS scores (R(2)=0.02, p=0.49). The full model, including psychosocial factors significantly associated with VAS scores explained 18.9% of the variance in VAS pain perception scores (R(2)=0.19, p=0.02). The Zung Depression Scale score was the only factor independently associated with VAS pain, such that higher depression scores were associated with higher VAS ratings (ß =0.13, p<0.01), controlling for gender, age, SES, STAI-State, STAI-Trait, ISEL tangible, SCL-90R GSI, and SCL-90R PST. CONCLUSIONS: Depressive symptoms, anxiety, social support, and psychopathological symptom distress were associated with pain ratings, but only depressive symptoms were found to be uniquely associated with higher pain perception, taking into account socio-demographic characteristics and other psychosocial factors. Findings provide evidence for the need to assess and treat pain in RA in Colombia from a bio-psycho-social perspective. Future research is needed to determine effective depression screening and evidence-based interventions for depressive symptoms in RA patients in this socio-cultural context, as intervening in depression may decrease pain perception.

Ultra-wide detuning planar Bragg grating fabrication technique based on direct UV grating writing with electro-optic phase modulation.

A direct UV grating writing technique based on phase-controlled interferometry is proposed and demonstrated in a silica-on-silicon platform, with a wider wavelength detuning range than any previously reported UV writing technology. Electro-optic phase modulation of one beam in the interferometer is used to manipulate the fringe pattern and thus control the parameters of the Bragg gratings and waveguides. Various grating structures with refractive index apodization, phase shifts and index contrasts of up to 0.8 × 10(-3) have been demonstrated. The method offers significant time/energy efficiency as well as simplified optical layout and fabrication process. We have shown Bragg gratings can be made from 1200 nm to 1900 nm exclusively under software control and the maximum peak grating reflectivity only decreases by 3 dBover a 250 nm (~32 THz) bandwidth.

Phase controlled integrated interferometric single-sideband filter based on planar Bragg gratings implementing photonic Hilbert transform.

The monolithically integrated all-optical single-sideband (SSB) filter based on photonic Hilbert transform and planar Bragg gratings is proposed and experimentally demonstrated. An SSB suppression of 12 dB at 6 GHz and sideband switching are achieved via thermal tuning. An X-coupler, photonic Hilbert transformer, flat top reflector, and a micro heater are incorporated in a single silicon-on-silica substrate. The device can be thermally tuned by the micro heater on top of the channel waveguide. The device is fabricated using a combination of direct UV grating writing technology and photolithography.

Health problems associated with international business travel. A critical review of the literature.

1. Few studies examine the travel related health problems of international business travelers (IBTs). Research exists for other travelers, such as tourists, which begins to help clinicians understand the potential health problems faced by IBTs. 2. A review of the literature reveals 36% to 54% of travelers experience physical health problems such as traveler's diarrhea, insomnia, respiratory problems, and skin problems; 6% to 18% report accidents and injuries while abroad. 3. Psychosocial data are equally limited, but support the idea that IBTs may experience stress, anxiety, culture shock, and adjustment problems while overseas. 4. Multiple factors likely contribute to the physical and psychosocial health experiences of IBTs. The historical lack of data for this population of workers combined with the trend towards globalization confirm the need for further study from an occupational health perspective.

Mapping a social network of heterosexuals at high risk for HIV infection.

OBJECTIVE: To determine how heterosexuals at risk for HIV infection interconnect in social networks and how such relationships affect HIV transmission. DESIGN: Cross-sectional study with face-to-face interviews to ascertain sociosexual connections; serologic testing. PARTICIPANTS: Prostitute women (n = 133), their paying (n = 129) and non-paying (n = 47) male partners; injecting drug users (n = 200) and their sex partners (n = 41). Participants were recruited in sexually transmitted disease and methadone clinics, an HIV-testing site, and through street outreach in Colorado Springs, Colorado, USA. MAIN OUTCOME MEASURES: Reported behaviors, risk perceptions, sociosexual linkages, and HIV prevalence. RESULTS: Respondents were well informed, but reported engaging in high-risk behaviors frequently. Nevertheless, over 70% of respondents perceived themselves to be at low risk for HIV infection. The 595 respondents identified a social network of 5162 people to which they belonged. Network analytic methods indicated 147 separate connected components of this network; eight of the 19 HIV-positive individuals in the network were located in smaller components remote from the largest connected component. CONCLUSION: The isolated position of HIV-positive individuals may serve as a barrier to HIV transmission and may account for the lack of diffusion of HIV in heterosexual populations in this region. Network analysis appears useful for understanding the dynamics of disease transmission and warrants further development as a tool for intervention and control.