We report that double-stranded DNA collapses in presence of a.c. electric fields at frequencies of a few hundred Hertz, and does not stretch as commonly assumed. In particular, we show that confinement-stretched DNA can collapse to about one quarter of its equilibrium length. We propose that this effect is based on finite relaxation times of the counterion cloud, and the subsequent partitioning of the molecule into mutually attractive units. We discuss alternative models of those attractive units.
We apply digital image analysis techniques to study selected types of melanocytic lesions.
Methods and Results
We used advanced digital image analysis to compare melanocytic lesions. All comparisons were statistically significant (p < 0.0001) and we highlight four: 1) melanoma to nevi, 2) melanoma subtypes to nevi, 3) severely dysplastic nevi to other nevi, and 4) melanoma to severely dysplastic nevi. We were successful in differentiating melanoma from nevi (ROC area 0.95) using image-derived features. While many features contribute to separation, analysis revealed features related to nuclear size, shape, and distance between nuclei to be most important. Dividing melanoma into subtypes, even greater separation was obtained (ROC area 0.98 for superficial spreading melanoma; 0.95 for lentigo maligna melanoma; and 0.99 for unclassified). Severely dysplastic nevi were best differentiated from conventional and mildly dysplastic nevi by differences in cellular staining qualities (ROC area 0.84). We found that melanoma were separated from severely dysplastic nevi by features related to cell shape and cellular staining qualities (ROC area 0.95).
We offer a unique perspective into the evaluation of melanocytic lesions and demonstrate a technological application with increasing prevalence, with potential use as an adjunct to traditional diagnosis in the future.
Advances in antiretroviral medications have resulted in precipitous declines in HIV-associated morbidity and mortality; however, high levels of adherence are crucial to the success of HIV therapies. This article reviews published studies in the United States on HIV-infected youth (ages 13 to 24 years), focusing on adherence to antiretroviral regimens and interventions designed to enhance adherence. A systematic search yielded 21 articles published between 1999 and 2008 that reported data on medication adherence in HIV-infected youth, of which 7 described unique interventions to enhance medication adherence. Five thematic areas were identified to classify factors associated with adherence. Findings suggest psychosocial factors, in particular depression and anxiety, were consistently associated with poorer adherence across studies. Three types of adherence interventions with HIV-infected youth were found. Results suggest that examining adherence within the broader contextual issues present in the lives of youth, including HIV stigma and disclosure, caregiver stress, peer relations, mental health and substance use, and length of time on medications, may be most important to understanding how best to intervene with adherence among this population. Secondary HIV prevention interventions for youth represent a possible mode through which to deliver individually tailored adherence skill building and counseling to improve medication adherence.
An emerging HIV epidemic can be seen among men who have sex with men (MSM) in Vietnam, with prevalence as high as 18%. Transactional sex represents a risk factor for HIV transmission/acquisition among MSM globally, particularly in urban contexts, but remains largely underinvestigated in Ho Chi Minh City (HCMC), Vietnam. In 2010, 23 MSM who reported exchanging sex for money in the last month completed a brief survey and semistructured qualitative interview at The Life Centre, a non-governmental organization in HCMC, to assess sociodemographics, individual- and structural-level HIV risk factors and explore acceptable future prevention interventions. Participants’ mean age was 24 years. Equal proportions of respondents self-identified as heterosexual/straight, homosexual/gay, and bisexual. Participants had a mean of 158 male clients in the past year, with a median of 60 male clients in the past year (interquartile range [IQR]=70) and reported inconsistent condom use and inaccurate perceptions of HIV risk. Nearly half of the sample reported engaging in unprotected anal sex with a male partner in the past 12 months and one-third with a male client. Major themes that emerged for HIV prevention interventions with male sex workers were those that: (1) focused on individual factors (drug and alcohol use, barriers to condom use, knowledge of asymptomatic STIs, enhancement of behavioral risk-reduction skills, and addressing concomitant mental health issues); (2) incorporated interpersonal and relational contexts (led by peer educators, built interpersonal skills, attended to partner type and intimacy dynamics); and (3) considered the exogenous environments in which individual choices/relationships operate (stigma of being MSM in Vietnam, availability of alternative economic opportunities, and varied sexual venues). HIV prevention efforts are needed that address the specific needs of MSM who engage in transactional sex in HCMC. Universally, MSM endorsed HIV prevention interventions, suggesting a need and desire for efforts in this context.
HIV; Vietnam; prevention; male sex workers; transactional sex
Male-to-female transgender individuals who engage in sex work constitute a group at high risk for HIV infection in the United States. This mixed-methods formative study examined sexual risk among preoperative transgender male-to-female sex workers (N = 11) in Boston. More than one third of the participants were HIV-infected and reported a history of sexually transmitted diseases. Participants had a mean of 36 (SD = 72) transactional male sex partners in the past 12 months, and a majority reported at least one episode of unprotected anal sex. Qualitative themes included (a) sexual risk, (b) motivations for engaging in sex work, (c) consequences of sex work, (d) social networks (i.e., “trans mothers,” who played a pivotal role in initiation into sex work), and (e) potential intervention strategies. Results suggest that interventions with transgender male-to-female sex workers must be at multiple levels and address the psychosocial and environmental contexts in which sexual risk behavior occurs.
HIV; intervention development; sexually transmitted diseases; transgender; trans mothers
Particulate air pollution, including from motor vehicles, is associated with cardiovascular disease.
To describe lessons learned from installing air filtration units in public housing apartments next to a major highway.
We reviewed experience with recruitment, retention and acceptance of the air filtration units.
Recruitment and retention have been challenging, but similar to other studies in public housing. Equipment noise and overheated apartments during hot weather have been notable complaints from participants. In addition, we found that families with members with Alzheimer’s or mental disability were less able to tolerate the equipment.
For this research the primary lesson is that working closely with each participant is important. A future public health program would need to address issues of noise and heat to make the intervention more acceptable to residents.
Particulate matter; CBPR; community-based participatory research; public housing; air filtration; cardiovascular disease
Men who have sex with men (MSM) in India are a core risk group for HIV. Heavy alcohol consumption is associated with increased sexual risk-taking behaviours in many cultures, in particular among MSM. However, no studies to date have explored alcohol use and HIV risk among MSM in India. MSM in Chennai, India (n = 210) completed an interviewer-administered behavioural and psychosocial assessment. Bivariate and multivariable logistic regression procedures examined behavioural and demographic associations with weekly alcohol consumption. Twenty-eight percent of the sample (n = 58) reported using alcohol at least weekly to the point of being buzzed/intoxicated, which was associated with older age, being married to a woman, being panthi (masculine appearing, predominantly insertive partners) versus kothi (feminine acting/appearing and predominantly receptive partners), weekly tobacco use, unprotected anal sex and unprotected vaginal sex in the three months prior to study enrolment (all P < 0.05). In a multivariable model, unprotected vaginal sex in the previous three months and being married to a women were unique variables associated with weekly alcohol use (all P < 0.01). Further investigation of alcohol use within the context of sexual risk taking is warranted among Indian MSM. Panthis and MSM who are married to women may be particularly likely to benefit from interventions to decrease alcohol intake and concurrent unsafe sex.
men who have sex with men (MSM); alcohol; HIV; sexually transmitted infections (STI); prevention; intervention; India
We assessed the extent to which Centers for Disease Control and Prevention (CDC) recommendations have influenced routine HIV testing among Massachusetts community health center (CHC) personnel, and identified specific barriers and facilitators to routine testing.
Thirty-one CHCs were enrolled in the study. We compared those that did and did not receive funding support from the federal Ryan White HIV/AIDS Program. An anonymous survey was administered to a maximum five personnel from each CHC, including a senior administrator, the medical director, and three medical providers. Overall, 137 participants completed the survey.
Among all CHCs, 53% of administrators reported having implemented routine HIV testing at their CHCs; however, only 33% of medical directors/providers reported having implemented routine HIV testing in their practices (p<0.05). Among administrators, 60% of those from Ryan White-supported CHCs indicated that both they and their CHCs were aware of CDC's recommendations, compared with 27% of administrators from non-Ryan White-supported CHCs. The five most frequently reported barriers to the implementation of routine HIV testing were (1) constraints on providers' time (68%), (2) time required to administer counseling (65%), (3) time required to administer informed consent (52%), (4) lack of funding (35%), and (5) need for additional training (34%). In a multivariable logistic regression model, the provision of on-site HIV testing by nonmedical staff resulted in increased odds of conducting routine HIV testing (odds ratio [OR] = 9.84, 95% confidence interval [CI] 1.77, 54.70). However, the amount of time needed to administer informed consent was associated with decreased odds of providing routine testing (OR=0.21, 95% CI 0.05, 0.92).
Routine HIV testing is not currently being implemented uniformly among Massachusetts CHCs. Future efforts to increase implementation should address personnel concerns regarding time and staff availability.
► Toddlers’ day care entry and their settling-in processes. ► At entry to care, toddlers’ levels of affect and interaction were low. ► Overall, change in toddlers’ behaviour over the first four months in care was less than expected. ► Significant individual differences in change in all measured areas of behaviour. ► Significant associations between toddlers’ affect, interaction and exploratory interest.
This study investigates toddlers’ initial reaction to day care entry and their behaviour change over the first few months in care. One hundred and four toddlers (10–33 months of age) in Viennese childcare centres participated in the study. One-hour video observations were carried out at 3 time points during the first 4 months in the setting and coded into a total of 36 5-min observation segments. Multilevel models (observation segments nested within children) with an autoregressive error structure fitted data well. Two weeks after entry into care, toddlers’ levels of affect and interaction were low. Overall, changes in all areas of observed behaviour were less than expected. There were considerable individual differences in change over time, mostly unrelated to child characteristics. Significant associations between children's positive affect, their dynamic interactions and their explorative and investigative interest were found.
Childcare; Transition; Multilevel model; Interaction; Affect; Interest
To compare invasive blood pressure (BP) measurements recorded using an automated archiving method against clinician-documented values from the same invasive monitor, and determine which method of recording BP is more highly associated with the subsequent onset of hypotension.
Retrospective comparative analysis.
Intensive care patients in a university hospital.
Mixed medical/surgical patients.
Using intervals of hemodynamic stability from 2,320 patient records, we retrospectively compared paired sources of invasive BP data: (1) measurements documented by the nursing (RN) staff; and (2) measurements generated by an automated archiving method that intelligently excludes unreliable (e.g., noisy or excessively damped) BP values. The primary outcome was the occurrence of subsequent “consensus” hypotension, i.e., hypotension documented jointly by the RN and the automated archive.
The automated method could be adjusted to alter its operating characteristics (sensitivity and specificity). At a matched level of specificity (96%), BP from the automated archiving method was more sensitive (28%) for subsequent “consensus” hypotension versus the RN documented values (21%). Likewise, at a matched level of sensitivity (21%), the automated method was more specific (99%) versus the RN documented values (96%). These significant findings (p < 0.001) were consistent in a set of sensitivity analyses which employed alternative criteria for patient selection and the clinical outcome definition.
During periods of hemodynamic stability in an ICU patient population, clinician-documented BP values were inferior to an intelligent automated archiving method, as early indicators of hemodynamic instability. Human oversight may not be necessary for creating a valid archive of vital signs data within an electronic medical record. Moreover, if clinicians do have a tendency to disregard early indications of instability, then an automated archive may be a preferable source of data for so-called Early Warning Systems that identify patients at-risk of decompensation.
Hypotension; Intensive Care; Physiologic Monitoring; Electronic Medical Record; Digital Signal Processing; Automatic Data Processing
► We monitored extent of IncF plasmid R1 spread during agar surface matings in situ. ► A zygotic induction strategy was used to visualize fluorescent transconjugants. ► Plasmids did not spread beyond the first five recipient cell layers adjacent to the donor cells. ► Derepressed IncF plasmid R1drd19 reduces swarming ability.
Most natural conjugative IncF plasmids encode a fertility inhibition system that represses transfer gene expression in the majority of plasmid-carrying cells. The successful spread of these plasmids in clinically relevant bacteria has been suggested to be supported by a transitory derepression of transfer gene expression in newly formed transconjugants. In this study, we aimed to monitor the extent of transitory derepression during agar surface matings in situ by comparing plasmid spread of the IncF plasmid R1 and its derepressed mutant R1drd19 at low initial cell densities. A zygotic induction strategy was used to visualize the spatial distribution of fluorescent transconjugants within the heterogeneous environment. Epifluorescence and confocal microscopy revealed different transfer patterns for both plasmids, however, spread beyond the first five recipient cell layers adjacent to the donor cells was not observed. Similar results were observed for other prototypical conjugative plasmids. These results cannot rule out that transitory derepression contributes to the limited R1 plasmid invasion, but other factors like nutrient availability or spatial structure seem to limit plasmid spread.
Bacterial conjugation; Transitory derepression; IncF plasmid; Swarming; In situ monitoring; Reporter gene
Intracranial metastasis of neuroblastoma (IMN) is associated with poor survival. No curative therapy for the treatment of IMN currently exists. Unfractionated radiotherapy may be beneficial in the treatment of IMN given the known radiosensitivity of neuroblastoma as well as its proclivity to metastasize as discrete lesions. We present two patients with IMN treated with Gamma Knife stereotactic radiosurgery (SRS). Single-fraction radiotherapy yielded temporary reduction of tumor burden and stability of disease in both patients. SRS may be a useful palliative tool in the treatment of IMN and expands the overall treatment options for this disease.
Multiple methods for non-invasive measurement of cardiac output (CO) and stroke volume (SV) exist. Their comparative capabilities are not clearly established.
Healthy human subjects (n=21) underwent central hypovolaemia through progressive lower body negative pressure (LBNP) until the onset of presyncope, followed by termination of LBNP, to simulate complete resuscitation. Measurement methods were electrical bioimpedance (EBI) of the thorax and three measurements of CO and SV derived from the arterial blood pressure (ABP) waveform: the Modelflow (MF) method, the long-time interval (LTI) method, and pulse pressure (PP). We computed areas under receiver-operating characteristic curves (ROC AUCs) for the investigational metrics, to determine how well they discriminated between every combination of LBNP levels.
LTI and EBI yielded similar reductions in SV during progressive hypovolaemia and resuscitation (correlation coefficient 0.83) with ROC AUCs for distinguishing major LBNP (−60 mm Hg) vs resuscitation (0 mm Hg) of 0.98 and 0.99, respectively. MF yielded very similar reductions and ROC AUCs during progressive hypovolaemia, but after resuscitation, MF-CO did not return to baseline, yielding lower ROC AUCs (ΔROC AUC range, −0.18 to −0.26, P<0.01). PP declined during hypovolaemia but tended to be an inferior indicator of specific LBNP levels, and PP did not recover during resuscitation, yielding lower ROC curves (P<0.01).
LTI, EBI, and MF were able to track progressive hypovolaemia. PP decreased during hypovolaemia but its magnitude of reduction underestimated reductions in SV. PP and MF were inferior for the identification of resuscitation.
arterial pressure, measurement; blood, loss; cardiovascular system, responses; equipment, finapres; monitoring, cardiopulmonary
The induction of immune tolerance by specific agents, as opposed to general immune suppression, is a most desirable goal in transplantation biology. One approach to attain this goal is afforded by the use of donor-derived cells endowed with veto activity, which is the ability of a cell to specifically suppress only T cells directed against its antigens. A megadose of purified veto CD34+ hematopoietic stem cells is already used in patients to allow hematopoietic stem cells transplantation (HSCT) across major genetic barriers, while avoiding severe graft versus host disease (GVHD). However, allowing engraftment of such T cell-depleted HSCT under safer reduced intensity conditioning (RIC) protocols still remains a challenge. Therefore, combining megadose of CD34+ HSCT with other GVHD-depleted veto cells could enable facilitation of engraftment of HSCT under RIC without the adverse complication of GVHD. This approach might provide a safer modality for enabling engraftment of HSCT, enabling its application in elderly patients who cannot tolerate intensive protocols and to a variety of patients with non-malignant disorders, associated with longer life expectancy, in whom the use of a high risk conditioning cannot be considered.
veto; hematopoietic stem cell transplantation; megadose; CD34+ cells; anti-third-party CD8+ Tcm
Evidence-based HIV prevention interventions with men who have sex with men (MSM) in the United States have moderate effect sizes in reducing HIV sexual risk behavior. Mental health and psychosocial problems, which both disproportionately affect MSM populations and are implicated in HIV transmission risk behaviors, also likely interfere with the uptake of HIV behavioral interventions. Moreover, given that mental health and psychosocial problems such as depression, substance use, and violence frequently co-occur for many MSM (eg, as “syndemic conditions”), what is probably needed are combination prevention efforts, or prevention “cocktails,” similar to treatment “cocktails,” that address the psychological and behavioral mechanisms that interact to produce elevated risk for HIV. Such interventions should incorporate a holistic framework to address the sexual health and overall well-being of MSM. Addressing co-occurring psychosocial risk factors is apt to improve effect sizes of current HIV prevention interventions and allow for more effective uptake by MSM.
The recurrence rate of anti-SSA/Ro associated congenital heart block (CHB) is 17%. Reversal of 3rd degree block has never been achieved. Based on potential reduction of maternal autoantibody titers as well as fetal inflammatory responses, IVIG was evaluated as a preventative therapy for CHB.
A multicenter open-label study based on Simon’s 2-stage optimal design was initiated. Enrollment criteria included: maternal anti-SSA/Ro antibody, a previous child with CHB/rash, = 20 mg prednisone, < 12 weeks pregnant. IVIG (400mg/kg) was given every 3 weeks from 12 to 24 weeks of gestation. The primary outcome was the development of 2nd or 3rd degree CHB.
Twenty mothers completed the IVIG protocol before reaching the pre-determined stopping rule of three cases of advanced CHB. CHB was detected at 19, 20 and 25 weeks; none followed an abnormal PR interval. One of these mothers had two previous children with CHB. One child without CHB developed a transient rash consistent with neonatal lupus. Sixteen children had no manifestations of neonatal lupus at birth. No significant changes in maternal antibody titers to SSA/Ro, SSB/La, or Ro52 were detected over the course of therapy or at delivery. There were no safety issues.
IVIG at doses consistent with replacement does not prevent the recurrence of CHB or reduce maternal antibody titers. Having established safety with this protocol and feasibility of patient enrollment, subsequent preventative studies may be considered, perhaps to include higher doses of IVIG.
Congenital Heart Block; Intravenous Immunoglobulin; anti-SSA/Ro antibodies; neonatal lupus
Ukraine has one of the most severe HIV/AIDS epidemics in Europe, with an estimated 1.63% of the population living with HIV/AIDS in 2007. Injection drug use (IDU) remains the predominant mode of transmission in Kiev—the capital and largest city. Prior reports suggest that the HIV infection rate among IDUs in Kiev reaches 33%, and many have poor and inequitable access to highly active antiretroviral therapy (HAART). Among those with access to HAART, little is understood about barriers and facilitators to HAART medication adherence.
In 5/2009, two semi-structured focus groups were conducted with HIV-infected IDUs seeking treatment at the City AIDS Center, Kiev. The goal was to use this information to adapt and tailor, to Ukrainian culture, an evidence-based intervention for improving adherence to HAART. All 16 participants attributed HIV infection to IDU. Their average age was 31.6 (SD=7.0), average time with HIV 5.7 years (SD=4.0), average time on HAART 2.5 years (SD=1.7), average time as IDU 14.6 years (SD=6.8), and 88% were on opioid substitution therapy.
The most salient themes related to adherence barriers included: (1) harassment and discrimination by police; (2) opioid dependence; (3) complexity of drug regimen; (4) side effects; (5) forgetting; (6) co-occurring mental health problems; and (7) HIV stigma. Facilitators of adherence included: (1) cues for pill taking; (2) support and reminders from family, significant other, and friends; (3) opioid substitution therapy; and (4) wanting improved health. Additional factors explored included: 1) knowledge about HAART; (2) storage of medications; and (3) IDU and sexual risk behaviors.
Findings highlighted structural and individual barriers to adherence. At the structural level, police discrimination and harassment was reported to be a major barrier to adherence to opioid substitution therapy and HAART. Privacy and stigma were barriers at the individual level. Recommendations for adherence interventions included education, training, and identification cards to show police that medication was for treatment of HIV, not for abuse; and involving family members and other systems of support for HIV treatment.
HIV; ARV; IDU; Ukraine; opioid substitution therapy; adherence
This tutorial review describes recent progress in modeling the active sites of carboxylate-rich non-heme diiron enzymes that activate dioxygen to carry out several key reactions in nature. The chemistry of soluble methane monooxygenase, which catalyzes the selective oxidation of methane to methanol, is of particular interest for (bio)technological applications. Novel synthetic diiron complexes that mimic structural, and, to a lesser extent, functional features of these diiron enzymes are discussed. The chemistry of the enzymes is also briefly summarized. A particular focus of this review is on models that mimic characteristics of the diiron systems that were previously not emphasized, including systems that contain (i) aqua ligands, (ii) different substrates tethered to the ligand framework, (iii) dendrimers attached to carboxylates to mimic the protein environment, (iv) two N-donors in a syn-orientation with respect to the iron-iron vector, and (v) a N-rich ligand environment capable of accessing oxygenated high-valent diiron intermediates.
The sexual health of transmen—individuals born or assigned female at birth and who identify as male—remains understudied. Given the increasing rates of HIV and sexually transmitted diseases (STDs) among gay and bisexual men in the United States, understanding the sexual practices of transmen who have sex with men (TMSM) may be particularly important to promote sexual health or develop focused HIV prevention interventions. Between May and September 2009, 16 transmen who reported sexual behavior with nontransgender men completed a qualitative interview and a brief interviewer-administered survey. Interviews were conducted until redundancy in responses was achieved. Participants (mean age, 32.5, standard deviation [SD] = 11.1; 87.5% white; 75.0% “queer”) perceived themselves at moderately high risk for HIV and STDs, although 43.8% reported unprotected sex with an unknown HIV serostatus nontransgender male partner in the past 12 months. The majority (62.5%) had used the Internet to meet sexual partners and “hook-up” with an anonymous nontransgender male sex partner in the past year. A lifetime STD history was reported by 37.5%; 25.0% had not been tested for HIV in the prior 2 years; 31.1% had not received gynecological care (including STD screening) in the prior 12 months. Integrating sexual health information “by and for” transgender men into other healthcare services, involving peer support, addressing mood and psychological wellbeing such as depression and anxiety, Internet-delivered information for transmen and their sexual partners, and training for health care providers were seen as important aspects of HIV and STD prevention intervention design and delivery for this population. “Embodied scripting” is proposed as a theoretical framework to understand sexual health among transgender populations and examining transgender sexual health from a life course perspective is suggested.
We sought to develop an intensive care unit research database applying automated techniques to aggregate high-resolution diagnostic and therapeutic data from a large, diverse population of adult intensive care unit patients. This freely available database is intended to support epidemiologic research in critical care medicine and serve as a resource to evaluate new clinical decision support and monitoring algorithms.
Data collection and retrospective analysis.
All adult intensive care units (medical intensive care unit, surgical intensive care unit, cardiac care unit, cardiac surgery recovery unit) at a tertiary care hospital.
Adult patients admitted to intensive care units between 2001 and 2007.
Measurements and Main Results
The Multiparameter Intelligent Monitoring in Intensive Care II (MIMIC-II) database consists of 25,328 intensive care unit stays. The investigators collected detailed information about intensive care unit patient stays, including laboratory data, therapeutic intervention profiles such as vasoactive medication drip rates and ventilator settings, nursing progress notes, discharge summaries, radiology reports, provider order entry data, International Classification of Diseases, 9th Revision codes, and, for a subset of patients, high-resolution vital sign trends and waveforms. Data were automatically deidentified to comply with Health Insurance Portability and Accountability Act standards and integrated with relational database software to create electronic intensive care unit records for each patient stay. The data were made freely available in February 2010 through the Internet along with a detailed user’s guide and an assortment of data processing tools. The overall hospital mortality rate was 11.7%, which varied by critical care unit. The median intensive care unit length of stay was 2.2 days (interquartile range, 1.1–4.4 days). According to the primary International Classification of Diseases, 9th Revision codes, the following disease categories each comprised at least 5% of the case records: diseases of the circulatory system (39.1%); trauma (10.2%); diseases of the digestive system (9.7%); pulmonary diseases (9.0%); infectious diseases (7.0%); and neoplasms (6.8%).
MIMIC-II documents a diverse and very large population of intensive care unit patient stays and contains comprehensive and detailed clinical data, including physiological waveforms and minute-by-minute trends for a subset of records. It establishes a new public-access resource for critical care research, supporting a diverse range of analytic studies spanning epidemiology, clinical decision-rule development, and electronic tool development.
databases; clinical decision support; hemodynamic instability; information technology; patient monitoring
The value of different algorithms that estimate cardiac output (CO) by analysis of a peripheral arterial blood pressure (ABP) waveform has not been definitively identified. In this investigation, we developed a testing data set containing a large number of radial ABP waveform segments and contemporaneous reference CO by thermodilution measurements, collected in an intensive care unit (ICU) patient population during routine clinical operations. We employed this data set to evaluate a set of investigational algorithms, and to establish a public resource for the meaningful comparison of alternative CO-from-ABP algorithms.
A retrospective comparative analysis of eight investigational CO-from-ABP algorithms using the Multiparameter Intelligent Monitoring in Intensive Care II database.
Mixed medical/surgical ICU of a university hospital.
A total of 120 cases.
CO estimated by eight investigational CO-from-ABP algorithms, and COTD as a reference.
All investigational methods were significantly better than mean arterial pressure (MAP) at estimating direction changes in COTD. Only the formula proposed by Liljestrand and Zander in 1928 was a significantly better quantitative estimator of COTD compared with MAP (95% limits-of-agreement with COTD: –1.76/+1.41 L/min versus –2.20/+1.82 L/min, respectively; p < 0.001, per the Kolmogorov-Smirnov test). The Liljestrand method was even more accurate when applied to the cleanest ABP waveforms. Other investigational algorithms were not significantly superior to MAP as quantitative estimators of CO.
Based on ABP data recorded during routine intensive care unit (ICU) operations, the Liljestrand and Zander method is a better estimator of COTD than MAP alone. Our attempts to fully replicate commercially-available methods were unsuccessful, and these methods could not be evaluated. However, the data set is publicly and freely available, and developers and vendors of CO-from-ABP algorithms are invited to test their methods using these data.
cardiac output; non-invasive monitoring; pulse contour; database; arterial blood pressure; thermodilution
Several recent studies have sought to elaborate upon the applicability and validity of respondent-driven sampling (RDS) to find hard-to-reach samples in general and men who have sex with men (MSM) in particular. Few published studies have elucidated the characteristics associated with initial RDS participants (“seeds”) who successfully recruited others into a study. A total of 74 original seeds were analyzed from four Massachusetts studies conducted between 2006 and 2008 that used RDS to reach high-risk MSM. Seeds were considered “generative” if they recruited two or more subsequent participants and “non-generative” if they recruited zero or one participant. Overall, 34% of seeds were generative. In separate multivariable logistic regression models controlling for age, race, health insurance, HIV status, and the study for which the seed was enrolled, unprotected anal sex in the past 12 months [adjusted odds ratio (AOR) = 6.68; 95% confidence interval (95% CI) = 1.27–35.12; p = 0.03], cocaine use during sex at least monthly during the past 12 months (AOR = 8.81; 95% CI = 1.68–46.27; p = 0.01), and meeting sex partners at social gatherings (AOR = 7.42; 95% CI = 1.58–34.76; p = 0.01) and public cruising areas (AOR = 4.92; 95% CI = 1.27–19.01; p = 0.02) were each significantly associated with increased odds of being a generative seed. These findings have methodological and practical implications for the recruitment of MSM via RDS. Finding ways to identify RDS seeds that are consistently generative may facilitate collecting a sample that is closer to reflecting the MSM who live in all of the communities in a given location or study sample.
MSM; Respondent-driven sampling; Methods; HIV
A hybrid enzyme-nanoparticle system is described for achieving clean reduction of CO2 to CO using visible light as the energy source. An aqueous dispersion of TiO2 nanoparticles modified by attachment of carbon monoxide dehydrogenase (CODH) and a Ru photosensitizer produces CO at a rate of 250 μmol CO (g TiO2)-1 h-1 when illuminated with visible light at pH 6 and 20 °C.
A growing body of research documents mental health disparities among women who have sex with women (WSW) compared to women who have sex with men only (WSM). However, there remains a dearth of research exploring these indicators alongside sexually transmitted diseases (STDs) and WSW sexual health.
A retrospective chart review was conducted of all female patients (n=368) screened for STDs between July 2007 and December 2007 at an urban community health center in Boston, MA. De-identified electronic medical record data (e.g., demographics, psychosocial, sexual health) were analyzed and linked to STD positivity. Women who did not have sexual behavior documented in their medical chart (n=58) were excluded from this analysis. Bivariate and multivariable logistic regression procedures examined sexual and psychosocial health indicators, including sexual preference.
Twenty-seven percent of participants were WSW (17% WSW only and 10% WSW/M). Overall, 5% of WSW were diagnosed with a new STD (HPV, anogenital warts, genital herpes, PID) and 17% had a history of a prior STD. In multivariable models adjusting for demographics, WSW were disproportionately more likely to have mental health and psychosocial issues noted in their medical records, including: a clinical diagnosis of depression, anxiety, and PTSD, history of suicide attempts, and inpatient psychiatric/mental health treatment. However, WSW were significantly less likely than WSM to engage in “high risk” HIV/STD sexual behavior. In a final multivariable model, same sex behavior was not associated with a different likelihood of being diagnosed with an STD, compared to opposite sex behavior. However, WSW diagnosed with STDs were at increased odds of having bipolar disorder and utilizing outpatient mental health counseling services compared to WSW without STDs. WSW with a history of STDs were at increased odds of having attempted suicide in the past, utilizing both outpatient and inpatient mental health treatment services, and having a history of injection drug use compared to WSW without a history of STDs.
WSW with STDs may have serious psychosocial problems. Further research is warranted to better understand the relationship between sexual behavior and health, as well as to guide the development of interventions to ameliorate health disparities among WSW, particularly in the psychosocial domain.
women; WSW; STDs; health disparities; sexual health
To characterize behavioral circumstances of bites to children by dogs presented to a veterinary behavior clinic.
Retrospective case series examining medical records of dogs presenting by referral to a university veterinary hospital for aggression and which had bitten a child <18 years old. Behavioral data included age of victim, familiarity with dog, and circumstances of bites.
Records of bites to 111 children were examined. Children <6 years old were most commonly bitten in association with resource guarding (44%), whereas older children were most commonly bitten in association with territory guarding (23%). Similarly, food guarding was the most common circumstance for bites to familiar children (42%) and territory guarding for bites to unfamiliar children (53%). Behavioral screening of the 103 dogs examined revealed resource guarding (61%) and discipline measures (59%) as the most common stimuli for aggression. Anxiety screens revealed abnormalities in 77% of dogs. Potential contributory medical conditions were identified/suspected in 50% of dogs. When history before presentation was known, 66% of dogs had never previously bitten a child, and 19% had never bitten any human. Most dogs (93%) were neutered, and 66% of owners had taken their dogs to obedience training classes.
Most children were bitten by dogs with no history of biting children. There is a high rate of behavioral abnormalities (aggression and anxiety) in this canine population. Common calming measures (neutering, training) were not routinely effective deterrents.
dog bite; dogs; child; aggression; animal behavior