Correction: Weight Gain Prevention Outcomes From a Pragmatic Digital Health Intervention With Community Health Center Patients: Randomized Controlled Trial

[This corrects the article DOI: 10.2196/50330.].

Awareness and Support of Responsive Bottle Feeding Among WIC Counselors and Caregivers: A Formative Qualitative Study

OBJECTIVE

To understand the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) counselor experiences discussing responsive bottle feeding during counseling and WIC participants' knowledge, understanding, and use of responsive bottle feeding.

METHODS

Qualitative descriptive, semistructured interviews with 23 participants (8 WIC counselors and 15 WIC participants) were conducted online via Zoom. The WIC counselors and mothers of WIC-enrolled bottle-fed infants were recruited through a network of WIC clinics in North Carolina. Interviews were recorded, transcribed, and collaboratively analyzed using content analysis.

RESULTS

The WIC participants received responsive infant feeding support from WIC counselors but often in the context of breastfeeding. WIC counselors provided valuable support for families but were challenged by limited training on responsive bottle feeding, balancing promoting breastfeeding with supporting mothers' feeding decisions, and time constraints.

CONCLUSIONS AND IMPLICATIONS

Findings provide preliminary support for the need to develop and pilot an intervention focused on promoting responsive feeding for parents of bottle-fed infants.

Weight Gain Prevention Outcomes From a Pragmatic Digital Health Intervention With Community Health Center Patients: Randomized Controlled Trial

BACKGROUND

The prevalence of obesity and its associated comorbidities continue to rise in the United States. Populations who are uninsured and from racial and ethnic minority groups continue to be disproportionately affected. These populations also experience fewer clinically meaningful outcomes in most weight loss trials. Weight gain prevention presents a useful strategy for individuals who experience barriers to weight loss. Given the often-limited weight management resources available to patients in primary care settings serving vulnerable patients, evaluating interventions with pragmatic designs may help inform the design of comprehensive obesity care delivered in primary care.

OBJECTIVE

This study aims to evaluate the effectiveness of Balance, a 2-arm, 12-month pragmatic randomized controlled trial of a digital weight gain prevention intervention, delivered to patients receiving primary care within federally qualified community health centers.

METHODS

Balance was a 2-arm, 12-month pragmatic randomized controlled trial of a digital weight gain prevention intervention delivered to individuals who had a BMI of 25-40 kg/m2, spoke English or Spanish, and were receiving primary care within a network of federally qualified community health centers in North Carolina. The Balance intervention was designed to encourage behavioral changes that result in a slight energy deficit. Intervention participants received tailored goal setting and tracking, skills training, self-monitoring, and responsive health coaching from registered dietitians. Weight was measured at regular primary care visits and documented in the electronic health record. We compared the percentage of ≤3% weight gain in each arm at 24 months after randomization-our primary outcome-using individual empirical best linear unbiased predictors from the linear mixed-effects model. We used individual empirical best linear unbiased predictors from participants with at least 1 electronic health record weight documented within a 6-month window centered on the 24-month time point.

RESULTS

We randomized 443 participants, of which 223 (50.3%) participants were allocated to the intervention arm. At baseline, participants had a mean BMI of 32.6 kg/m2. Most participants were Latino or Hispanic (n=200, 45.1%) or non-Latino or Hispanic White (n=115, 26%). In total, 53% (n=235) of participants had at least 1 visit with weight measured in the primary time window. The intervention group had a higher proportion with ≤3% weight gain at 6 months (risk ratio=1.12, 95% CI 0.94-1.28; risk difference=9.5, 95% CI -4.5 to 16.4 percentage points). This difference attenuated to the null by 24 months (risk ratio=1.00, 95% CI 0.82-1.20; risk difference=0.2, 95% CI -12.1 to 11.0 percentage points).

CONCLUSIONS

In adults with overweight or obesity receiving primary care at a community health center, we did not find long-term evidence to support the dissemination of a digital health intervention for weight gain prevention.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03003403; https://clinicaltrials.gov/study/NCT03003403.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.1186/s12889-019-6926-7.

Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

The Balance protocol: a pragmatic weight gain prevention randomized controlled trial for medically vulnerable patients within primary care

BACKGROUND

For patients with obesity who are not ready for or experience barriers to weight loss, clinical practice guidelines recommend provider counseling on preventing further weight gain as a first-line treatment approach. Unfortunately, evidence-based weight gain prevention interventions are not routinely available within primary care. To address this gap, we will implement a pragmatic 12-month randomized controlled trial of a digital weight gain prevention intervention delivered to patients receiving primary care within a network of Federally Qualified Community Health Centers in central North Carolina.

METHODS

Balance (Equilibrio in Spanish) is a pragmatic effectiveness trial that will randomize adult patients who have overweight or obesity (BMI of 25-40 kg/m²) to either: 1) a weight gain prevention intervention with tailored behavior change goals and tracking, daily weighing on a network-connected electronic scale, and responsive weight and goal coaching delivered remotely by health center registered dietitians; or 2) a usual care program with automated healthy living text messages and print materials and routine primary care. The primary outcome will be weight gain prevention at 24-months, defined as ≤3% change in baseline weight. To align with its pragmatic design, trial outcome data will be pulled from the electronic health record of the community health center network.

DISCUSSION

For underserved, often rurally-located patients with obesity, digital approaches to promote a healthy lifestyle can curb further weight gain. Yet enrolling medically vulnerable patients into a weight gain prevention trial, many of whom are from racial/ethnic minorities, can be difficult. Despite these potential challenges, we plan to recruit a large, diverse sample from rural areas, and will implement a remotely-delivered weight gain prevention intervention to medically vulnerable patients. Upcoming trial results will demonstrate the effectiveness of this pragmatic approach to implement and evaluate a digital weight gain prevention intervention within primary care.

TRIALS REGISTRATION

NCT03003403 . Registered December 28, 2016.

Effectiveness of an App and Provider Counseling for Obesity Treatment in Primary Care

INTRODUCTION

Obesity treatment is less successful for socioeconomically disadvantaged populations, particularly when delivered in primary care. Digital health strategies can extend the reach of clinical obesity treatments to care settings serving patients at highest risk.

METHODS

Track was an effectiveness RCT of a 12-month digital weight-loss intervention, embedded within a community health center system. Participants were 351 adult patients (aged 21-65 years) with obesity and hypertension, diabetes, and hyperlipidemia. Patients were randomized to usual care (n=175) or an intervention (n=176) comprising app-based self-monitoring of behavior change goals with tailored feedback, a smart scale, dietitian-delivered counseling calls, and clinician counseling informed by app-generated recommendations, delivered via electronic health record. The primary outcome was 12-month weight change. Randomization began on June 18, 2013, final assessments were completed on September 10, 2015. Data analysis was conducted in 2016 and 2017. The trial retained 92% of usual care and 96% of intervention participants at 12 months.

RESULTS

The Track intervention produced larger weight losses relative to usual care at 6 months (net effect: -4.4 kg, 95% CI= -5.5, -3.3, p<0.001) and 12 months (net effect: -3.8 kg, 95% CI= -5.0, -2.5, p<0.001). Intervention participants were more likely to lose ≥5% of their baseline weight at 6 months (43% vs 6%, p<0.001) and 12 months (40% vs 17%, p<0.001). Intervention participants completing ≥80% of expected self-monitoring episodes (-3.5 kg); counseling calls (-3.0 kg); or self-weighing days (-4.4 kg) lost significantly more weight than less engaged intervention participants (all p<0.01).

CONCLUSIONS

A digital obesity treatment, integrated with health system resources, can produce clinically meaningful weight-loss outcomes among socioeconomically disadvantaged primary care patients with elevated cardiovascular disease risk.

TRIAL REGISTRATION

This study is registered at www.clinicaltrials.gov NCT01827800.

Recommendations on multidisciplinary management of elective surgery in people with haemophilia

Planning and undertaking elective surgery in people with haemophilia (PWH) is most effective with the involvement of a specialist and experienced multidisciplinary team (MDT) at a haemophilia treatment centre. However, despite extensive best practice guidelines for surgery in PWH, there may exist a gap between guidelines and practical application. For this consensus review, an expert multidisciplinary panel comprising surgeons, haematologists, nurses, physiotherapists and a dental expert was assembled to develop practical approaches to implement the principles of multidisciplinary management of elective surgery for PWH. Careful preoperative planning is paramount for successful elective surgery, including dental examinations, physical assessment and prehabilitation, laboratory testing and the development of haemostasis and pain management plans. A coordinator may be appointed from the MDT to ensure that critical tasks are performed and milestones met to enable surgery to proceed. At all stages, the patient and their parent/caregiver, where appropriate, should be consulted to ensure that their expectations and functional goals are realistic and can be achieved. The planning phase should ensure that surgery proceeds without incident, but the surgical team should be ready to handle unanticipated events. Similarly, the broader MDT must be made aware of events in surgery that may require postoperative plans to be changed. Postoperative rehabilitation should begin soon after surgery, with attention paid to management of haemostasis and pain. Surgery in patients with inhibitors requires even more careful preparation and should only be undertaken by an MDT experienced in this area, at a specialized haemophilia treatment centre with a comprehensive care model.

Chiral encoding may provide a simple solution to the origin of life

The route by which the complex and specific molecules of life arose from the 'prebiotic soup' remains an unsolved problem. Evolution provides a large part of the answer, but this requires molecules that can carry information (that is, exist in many variants) and can replicate themselves. The process is commonplace in living organisms, but not so easy to achieve with simple chemical systems. It is especially difficult to contemplate in the chemical chaos of the prebiotic world. Although popular in many quarters, the notion that RNA was the first self-replicator carries many difficulties. Here, we present an alternative view, suggesting that there may be undiscovered self-replication mechanisms possible in much simpler systems. In particular, we highlight the possibility of information coding through stereochemical configurations of substituents in organic polymers. We also show that this coding system leads naturally to enantiopurity, solving the apparent problem of biological homochirality.

The 3-year evolution of a preschool physical activity intervention through a collaborative partnership between research interventionists and preschool teachers

Despite evidence that preschoolers spend the majority of their time in sedentary activities, few physical activity interventions have focused on preschool-age children. Health promotion interventions that can be integrated into the daily routines of a school or other setting are more likely to be implemented. The Study of Health and Activity in Preschool Environments employed a flexible approach to increasing physical activity opportunities in preschools' daily schedules through recess, indoor physical activity and physical activity integrated into academic lessons. Eight preschools were randomly assigned to receive the study's physical activity intervention. Teachers in these schools partnered with university-based interventionists across 3 years to design and implement a flexible and adaptive intervention. The intervention approach included trainings and workshops, site visits and feedback from intervention personnel, newsletters, and physical activity equipment and materials. Teachers reported a high acceptability of the intervention. The purpose of this article is to describe the evolution of a multi-component physical activity intervention in preschools, including (i) a description of the intervention components, (ii) an explanation of the intervention process and approach, and (iii) a report of teachers' perceptions of barriers to implementation.

Terahertz emission by diffusion of carriers and metal-mask dipole inhibition of radiation

Terahertz (THz) radiation can be generated by ultrafast photo-excitation of carriers in a semiconductor partly masked by a gold surface. A simulation of the effect taking into account the diffusion of carriers and the electric field shows that the total net current is approximately zero and cannot account for the THz radiation. Finite element modelling and analytic calculations indicate that the THz emission arises because the metal inhibits the radiation from part of the dipole population, thus creating an asymmetry and therefore a net current. Experimental investigations confirm the simulations and show that metal-mask dipole inhibition can be used to create THz emitters.

Supramolecular hetero-porphyrin SWNT complexes

The complexation of single walled carbon nanotubes (SWNTs) with neutral, anionic and cationic porphyrins has been investigated under identical complex forming conditions. The determination of the porphyrin loading reveals large differences depending on the nature of the porphyrin used. Combinations of different porphyrins to form mixed hetero-porphyrin complexes shows that the mixture of a cationic and anionic porphyrin results in loading which is an order of magnitude larger than in all other complexes. This complex also exhibits high adsorption and emission intensities and can be regarded as an extended co-operative binary ionic (CBI) solid. The complexes were further studied using Raman spectroscopy, elemental analysis, AFM and cyclic voltammetry.

Introducing structural flexibility into porphyrin-DNA zipper arrays

A more flexible nucleotide building block for the synthesis of new DNA based porphyrin-zipper arrays is described. Changing the rigid acetylene linker between the porphyrin substituent and the 2'-deoxyuridine to a more flexible propargyl amide containing linkage leads in part to an increased duplex stability. The CD spectra reveal different electronic interactions between the porphyrins depending on the type of linker used. Molecular modelling suggests large variation of the relative orientation of the porphyrins within the major groove of the DNA. The porphyrins can be metallated post-synthetically with different metals as shown with zinc, cobalt and copper. The spectroscopic features do not alter drastically upon metallation apart from the CD spectra, and the stability of the metal complex is highly dependent on the nature of the metal. As shown by CD spectroscopy, the zinc porphyrin is rapidly demetallated at high temperatures. Globular structure determination using SAXS indicates that a molecular assembly comprised of a two to four helical bundle dominates in solution at higher concentrations (≥50 μM) which is not observed by spectroscopy at lower concentrations (≤1 μM).

DNA as supramolecular scaffold for functional molecules: progress in DNA nanotechnology

Oligonucleotides have recently gained increased attraction as a supramolecular scaffold for the design and synthesis of functional molecules on the nanometre scale. This tutorial review focuses on the recent progress in this highly active field of research with an emphasis on covalent modifications of DNA; non-covalent interactions of DNA with molecules such as groove binders or intercalators are not part of this review. Both terminal and internal modifications are covered, and the various points of attachment (nucleobase, sugar moiety or phosphodiester backbone) are compared. Using selected examples of the recent literature, the diversity of the functionalities that have been incorporated into DNA strands is discussed.

Effects of gonadectomy on performance in operant tasks measuring prefrontal cortical function in adult male rats

Previous studies have shown that gonadectomy in adult male rats influences the acquisition and performance of spatial and other working memory tasks that depend in part on the medial prefrontal cortex and its dopamine innervation. Stimulated by previous findings that gonadectomy alters dopamine axon density in not only medial but several other prefrontal fields, the present studies asked whether gonadectomy might also broadly impact dopamine-dependent prefrontal functions, and whether these effects bore any relation to hormone modulation of mesoprefrontal dopamine afferents. Specifically, control, gonadectomized, and gonadectomized rats given estradiol or testosterone propionate were tested on a series of operant tasks that together measured medial prefrontal functions of spatial working memory, impulsivity and extradimensional set shifting and orbital prefrontal functions of reversal learning/perseveration and motivation. Afterwards, animals were sacrificed, their bulbospongiosus muscles were removed and weighed, their brains were processed for immunocytochemistry for the dopamine-synthesizing enzyme tyrosine hydroxylase, and axon densities were measured in orbital and medial prefrontal fields. Statistical evaluations of group effects on behavior and regression analyses comparing individual performance with muscle weights and axon density measures revealed androgen-reversible effects of gonadectomy on acquisition of spatial working memory and extradimensional set shifting that were correlated with bulbospongiosus weight and medial prefrontal dopamine axon density, estrogen-sensitive influences of gonadectomy on motivation and response withholding that were correlated with bulbospongiosus weight but not with dopamine innervation, and still other prefrontal functions, i.e., impulsivity, reversal learning, that were insensitive to gonadectomy and unrelated to gonadectomy-induced changes in muscle weight or prefrontal dopamine innervation.

Sodium reduction for hypertension prevention in overweight adults: further results from the Trials of Hypertension Prevention Phase II

Sodium reduction is efficacious for primary prevention of hypertension, but the feasibility of achieving this effect is unclear. The objective of the paper is detailed analyses of adherence to and effects of the sodium reduction intervention among overweight adults in the Trials of Hypertension Prevention, Phase II. Sodium reduction (comprehensive education and counselling about how to reduce sodium intake) was tested vs no dietary intervention (usual care) for 36-48 months. A total of 956 white and 203 black adults, ages 30-54 years, with diastolic blood pressure 83-89 mmHg, systolic blood pressure (SBP) <140 mmHg, and body weight 110-165% of gender-specific standard weight were included in the study. At 36 months, urinary sodium excretion was 40.4 mmol/24 h (24.4%) lower in sodium reduction compared to usual care participants (P<0.0001), but only 21% of sodium reduction participants achieved the targeted level of sodium excretion below 80 mmol/24 h. Adherence was positively related to attendance at face-to-face contacts. Net decreases in SBP at 6, 18, and 36 months of 2.9 (P<0.001), 2.0 (P<0.001), and 1.3 (P=0.02) mmHg in sodium reduction vs usual care were associated with an overall 18% lower incidence of hypertension (P=0.048); were relatively unchanged by adjustment for ethnicity, gender, age, and baseline blood pressure, BMI, and sodium excretion; and were observed in both black and white men and women. From these beneficial but modest results with highly motivated and extensively counselled individuals, sodium reduction sufficient to favourably influence the population blood pressure distribution will be difficult to achieve without food supply changes.

Staphylococcal species in the oral cavity from patients in a regional burns unit

The aim of this study was to perform a quantitative and qualitative analysis of oral carriage of staphylococci in a range of oral specimens from patients admitted to a regional burns unit. The study recruited 28 patients and reasons for admittance were: burns (46%), skin grafting (39%), lacerations (7%), scalding (4%) and necrotizing fasciitis (4%). No patient had smoke inhalation injuries or trauma to the oro-pharynx. There were five patients from whom methicillin-sensitive S. aureus (MRSA) could be detected in oral specimens. For three patients only the wound and oral specimens were positive for MRSA. In one patient only the oral specimens were positive for MRSA. There were five patients from whom methicillin-sensitive S. aureus (MRSA) could be detected in the oral specimens. In one patient only the oral specimens were positive for MSSA. Staphylococci could be recovered from the dental plaque, denture and toothbrush specimens with a mean count of 1.1 x 10(4)cfu/mL (range 20-5.3 x 10(4)), 5.4 x 10(3) (range 40-2.1 x 10(4)) and 264 cfu/mL (range 20-500), respectively. Both MSSA and MRSA could be recovered from these specimen types. In one patient only the toothbrush was positive for MRSA and all other oral specimens were negative. This study suggests that staphylococci are not infrequent colonizers of the oral cavity, and that this site may serve as a potential reservoir for transmission to other body sites.

Long-term weight loss and changes in blood pressure: results of the Trials of Hypertension Prevention, phase II

BACKGROUND

Weight loss appears to be an effective method for primary prevention of hypertension. However, the long-term effects of weight loss on blood pressure have not been extensively studied.

OBJECTIVE

To present detailed results from the weight loss arm of Trials of Hypertension Prevention (TOHP) II.

DESIGN

Multicenter, randomized dinical trial testing the efficacy of lifestyle interventions for reducing blood pressure over 3 to 4 years. Participants in TOHP II were randomly assigned to one of four groups. This report focuses only on participants assigned to the weight loss (n = 595) and usual care control (n = 596) groups.

PATIENTS

Men and women 30 to 54 years of age who had nonmedicated diastolic blood pressure of 83 to 89 mm Hg and systolic blood pressure less than 140 mm Hg and were 110% to 165% of their ideal body weight at baseline.

INTERVENTION

The weight loss intervention included a 3-year program of group meetings and individual counseling focused on dietary change, physical activity, and social support

MEASUREMENTS

Weight and blood pressure data were collected every 6 months by staff who were blinded to treatment assignment

RESULTS

Mean weight change from baseline in the intervention group was -4.4 kg at 6 months, -2.0 kg at 18 months, and -0.2 kg at 36 months. Mean weight change in the control group at the same time points was 0.1, 0.7, and 1.8 kg. Blood pressure was significantly lower in the intervention group than in the control group at 6, 18, and 36 months. The risk ratio for hypertension in the intervention group was 0.58 (95% CI, 0.36 to 0.94) at 6 months, 0.78 (CI, 0.62 to 1.00) at 18 months, and 0.81 (CI, 0.70 to 0.95) at 36 months. In subgroup analyses, intervention participants who lost at least 4.5 kg at 6 months and maintained this weight reduction for the next 30 months had the greatest reduction in blood pressure and a relative risk for hypertension of 0.35 (CI, 0.20 to 0.59).

CONCLUSIONS

Clinically significant long-term reductions in blood pressure and reduced risk for hypertension can be achieved with even modest weight loss.

Laparoscopic augmentation cystoplasty with different biodegradable grafts in an animal model

PURPOSE

Recently a variety of biodegradable organic materials have been used for bladder wall replacement. We sought to study the effectiveness of 4 different types of biodegradable materials for bladder augmentation using laparoscopic techniques.

MATERIALS AND METHODS

Thirty one minipigs underwent successful transperitoneal laparoscopic partial cystectomy and subsequent closure (6 control) or patch augmentation (25): porcine bowel acellular tissue matrix (ATM) (6), bovine pericardium (BPC) (6), human placental membranes (HPM) (6) or porcine small intestinal submucosa (SIS) (7). An intracorporeal suturing technique with the EndoStitch device (U.S. Surgical, Norwalk, CT) and Lapra-Ty clips (Ethicon, Enodsurgery Inc. Cincinnati, OH) was used to anastomose the graft to the bladder wall. Postoperatively, a urethral catheter was left for one week. Bladders were evaluated by cystoscopy at 6 and 12 weeks and harvested at 12 weeks.

RESULTS

Grafts remained in place in all groups except for the BPC group, where all grafts failed to incorporate. For the ATM and SIS groups, at 6 weeks, there was mucosal coverage of the grafts without evidence of encrustation. In the control group, at 12 weeks, the bladder capacity was 23% less than preoperatively. In the ATM, HPM and SIS groups, at 12 weeks, the bladder capacities were larger than preoperatively by 16%, 51% and 43% respectively; also the grafts had contracted to 70%, 65%, and 60% of their original sizes, respectively. Histologically, there was patchy epithelialization of ATM and SIS grafts with a mixture of squamoid and transitional cell epithelia. The graft persisted as a well-vascularized fibrous band in HPM, ATM, and SIS without evidence of significant inflammatory response.

CONCLUSION

A laparoscopic technique for partial bladder wall replacement using a free graft is feasible. The biodegradable grafts of ATM, HPM and SIS are tolerated by host bladder and are associated with predominantly only mucosal regeneration at 12 weeks post-operatively.

2-microm Doppler lidar transmitter with high frequency stability and low chirp

A coherent Doppler lidar system was frequency stabilized in a master-slave configuration by a phase-modulation technique. The short-term frequency stability, ~0.2 MHz rms, was maintained in a vibrational environment on a ship during a field campaign in the tropical Pacific Ocean. The long-term frequency stability was <2.6 kHz/h. Thus, in many applications, shot-to-shot frequency correction can be disregarded, which will result in increased speed and simplicity of the data-acquisition system. A frequency chirp could not be detected. These properties permit Doppler wind measurements with high efficiency and duty cycles to be made, even on airborne and spaceborne platforms.

The human and mouse GATA-6 genes utilize two promoters and two initiation codons

GATA-6 has been implicated in the regulation of myocardial differentiation during cardiogenesis. To determine how its expression is controlled, we have characterized the human and mouse genes. We have mapped their transcriptional start sites and demonstrate that two alternative promoters and 5' noncoding exons are utilized. Both transcript isoforms are expressed in the same tissue-specific and developmental stage-specific pattern, and their ratio appears similar wherever examined. The more upstream noncoding exon showed a substantial degree of homology between the two mammalian species, suggesting a conserved regulatory function. Moreover, in transfection assays we show that elements within this exon act to promote its transcription. Positive regulatory elements that effect transcription from the more downstream exon were not apparent in this assay, revealing a regulatory distinction between the two promoters. We also demonstrate alternative initiator codon usage in both the human and mouse GATA-6 genes. Both isoforms of the protein are synthesized in vitro regardless of which 5' noncoding exon is present in the RNA, although the larger protein has greater transcriptional activation potential in transfection assays. Thus, GATA-6 function in the cell is controlled by a complex interplay of transcriptional and translational regulation.

Laparoscopic replacement of urinary tract segments using biodegradable materials in a large-animal model

OBJECTIVE

We elected to evaluate laparoscopic segmental bladder and ureteral replacement with free biodegradable graft materials in a large-animal model.

MATERIALS AND METHODS

In 18 Yucatan minipigs, a 1.5- to 2.8-cm segment of the upper ureter was excised. In 15 study animals, the ureter was laparoscopically replaced: by a stinted (6F double-J stent) tube graft made of acellular matrix (AMX) prepared from minipig ureters (MUMX) in 6 animals, acellular matrix prepared from domestic pig ureters (DUMX) in 3, and small-intestinal submucosa (SIS) in 6. In 3 control animals, the ureteral gap was bridged only by an indwelling stent. The stent was removed at 6 weeks, and retrograde ureteropyelography was performed preoperatively and at 8 and 12 weeks postoperatively, when animals were sacrificed. In 18 Yucatan minipigs, 3 x 3-cm bladder dome segments were laparoscopically replaced: by acellular matrix prepared from minipig small bowel (MBMX) in 6 animals, and SIS in 6 animals. The bladder was closed primarily in 6 control animals. Bladder capacity was assessed preoperatively and at 6 and at 12 weeks, when the animals were sacrificed.

RESULTS

The average operating time for ureteral replacement was 187 (range 105-360) minutes. At 12 weeks, all animals had complete obstruction at the level of the replacement, with fibrosis +/- bone formation at the level of the stricture. For the bladder replacement groups, the average operating time was 147 (range 85-200) minutes. At 12 weeks, the bladder capacity was 60% of the preoperative capacity in the control group, 118% in the MBMX group, and 142% in the SIS group. Histologic examination showed regeneration of urothelium and some muscle with both MBMX and SIS.

CONCLUSIONS

We were able to develop a reliable laparoscopic technique for both segmental ureteral and partial bladder replacement in a porcine model. With AMX and SIS replacement, regeneration of urothelium occurred in both ureter and bladder. However, functional replacement was successful only in the bladder.

Pilot study to enhance start-up of a multicenter nutrition intervention trial

Multicenter trials are important for answering questions that require large numbers of subjects. Such trials require standardized implementation of behavioral change programs across diverse populations, regions, and staff. Researchers involved with the Trial of Nonpharmacologic Interventions in the Elderly conducted a 17-week pilot study of their most complex intervention (combined weight and sodium reduction) before actual start-up of the main study. This allowed staff to rehearse implementing the program and to identify and address intervention and standardization issues. Registered dietitians in 4 US communities recruited 28 participants for the pilot study, using eligibility criteria similar to those for the main trial. Participant evaluations reflected high satisfaction with the program materials and overall approach. Minor protocol changes suggested by results of the pilot study were made easily in time for start-up of the main study. Reductions in weight and sodium intake were less than targeted but were sufficient to suggest that the intervention would be effective under optimal conditions. This partial achievement of goals in the pilot study underscored the need to allow for a learning curve, for without it standardization and outcomes of the main study would be compromised.

Cardioprotective actions of verapamil on the beta-adrenergic receptor complex in acute canine Chagas' disease

The effect of verapamil treatment on the myocardial beta-adrenergic adenylyl cyclase complex in acute canine Chagas' disease was investigated. Relative to uninfected animals, 30 days of infection with T. cruzi reduced myocardial adenylyl cyclase activity by over 75%. With continuous verapamil treatment, the infection-associated reduction in adenylyl cyclase activity was less than 50%. The individual components of the beta-adrenergic receptor complex were characterized.

INFECTION

(1) increased right ventricular (RV) beta-adrenergic receptor (beta AR) density five-fold; (2) decreased left ventricle beta AR density by 20%; (3) reduced the proportion of high-affinity beta AR receptors to the same extent in both left and right ventricles; (4) reduced alpha s by 50% as determined by Western blot analysis, increased alpha 11-3 but did not change alpha 0; and (5) decreased the magnitude of pertussis-toxin-dependent [32P]ADP ribosylation by 60% as well as the proportion of [32P]ADP-ribose incorporated in alpha 0. Verapamil treatment of infected animals restored RV beta AR receptor density, alpha s and alpha i1-3 to control levels but had no influence on any aspect of pertussis-toxin-dependent [32P]ADP-ribosylation. Verapamil treatment of uninfected animals also: (1) increased beta-adrenergic adenylyl cyclase activity; (2) increased beta AR density in the RV but not the LV; (3) reduced high- to low-affinity beta-adrenergic receptors; and (4) affected only alpha i2 (50% decrease). The results indicate that the major actions of verapamil on the beta-adrenergic adenylyl cyclase complex in acute canine Chagas' disease may help to account for its cardioprotective effects.

Hepatitis C virus in saliva of haemophiliac patients attending an oral surgery unit

This study determined the frequency with which hepatitis C virus (HCV) could be detected in the saliva of 21 HCV-seropositive haemophiliac patients attending an Oral Surgery Unit. All sera were positive for HCV RNA by the polymerase chain reaction (PCR). Six of the patients were also HIV antibody positive. Saliva was collected both by spitting into a Universal container (whole saliva), and by means of Salivettes. Following RNA extraction from saliva specimens and synthesis of cDNA, nested PCR was performed. Amplified DNA was detected by agarose gel electrophoresis and ethidium bromide staining. Overall, HCV was detected in saliva from 10 of the subjects (8 HIV seronegative and 2 HIV seropositive) but there was not complete concordance between the Salivette specimens and normal whole saliva. Analysis of pellet and supernate fractions from whole saliva produced similar discrepancies. Repeat runs of PCR for HCV following freezing and thawing of the initially positive saliva specimens were unsuccessful. It was concluded that HCV is present in the saliva of some haemophiliac patients. However, careful optimisation of sample handling and storage methods and of PCR technique are required before the true prevalence of HCV shedding in saliva can be determined.

Selective vasodilator effects of atrial natriuretic peptide in the human placental vasculature

OBJECTIVE

To determine whether atrial natriuretic peptide (ANP) attenuates the vasoconstrictor effects of angiotensin II (AII), a thromboxane mimetic (U46619), and endothelin-1 in the human fetal-placental vasculature and to determine whether nitric oxide (NO) has a role in the vasodilator activity of ANP.

METHODS

Isolated placental cotyledons were dually perfused, with fetal perfusion pressure used as an index of vascular response. The effects of AII (10(-10)-10(-6) mol/L bolus injection), endothelin-1 (10(-7) mol/L bolus), and U46619 (10(-9)-10(-6) mol/L bolus or 10(-8) mol/L infusion) were established in the absence or presence of ANP (10(-8) mol/L). The role of NO as a mediator of ANP action was investigated by perfusion with n-nitro-L-arginine (NNLA, 10(-3) mol/L), an inhibitor of NO synthase. Statistical significance was determined by analysis of variance.

RESULTS

Atrial natriuretic peptide caused significant attenuation of vasoconstrictor responses to AII, but weak attenuation of endothelin-1 and no attenuation of U46619. Use of NNLA did not affect the attenuation of AII-induced vasoconstriction by ANP.

CONCLUSIONS

Atrial natriuretic peptide is a vasodilator of the fetal-placental vasculature constricted with AII and endothelin-1, but not with U46619. Nitric oxide does not mediate the action of ANP.

The action of two natriuretic peptides (atrial natriuretic peptide and brain natriuretic peptide) in the human placental vasculature

OBJECTIVE

Our purpose was to compare the actions of atrial natriuretic peptide and brain natriuretic peptide in the human placental vasculature.

STUDY DESIGN

Isolated placental cotyledons were dually perfused with fetal perfusion pressure used as an index of vascular response. The effect of angiotensin II (10(-10) to 10(-6) mol/L bolus injection) was established in the absence or presence of atrial natriuretic peptide (10(-8) mol/L) or brain natriuretic peptide (10(-8) mol/L final concentration). The role of nitric oxide as a mediator of natriuretic peptide action was investigated by perfusion of n-nitro-L-arginine (10(-3) mol/L), an inhibitor of nitric oxide synthase. Attenuation of the action of atrial natriuretic peptide by placental peptidases was studied by perfusion with the peptidase inhibitor benzamidine (2 x 10(-2) mol/L). Statistical significance was determined by analysis of variance and paired t test.

RESULTS

Significant attenuation of vasoconstrictor responses to angiotensin II occurred within both atrial natriuretic peptide and brain natriuretic peptide; however, brain natriuretic peptide was more effective. n-Nitro-L-arginine did not affect the attenuation of angiotensin II-induced vasoconstriction by atrial or brain natriuretic peptides. In the presence of benzamidine atrial natriuretic peptide exerted a significantly greater vasodilator effect.

CONCLUSION

Brain natriuretic peptide is a more potent vasodilator of the placental vasculature than is atrial natriuretic peptide. The low efficacy of atrial natriuretic peptide may be related to placental peptidases. Nitric oxide does not mediate the action of atrial natriuretic peptide or brain natriuretic peptide.

The Management of Dental Problems Presenting to an Accident and Emergency Department

Patients with dental diagnoses, not necessarily traumatic, often present to accident and emergency departments and general medical practitioners. Few doctors have received much, if any, education in the management of these patients. A 6 month prospective study revealed 107 patients (0.3% of new attenders) attending the accident and emergency department of Glasgow Royal Infirmary. Only 19 of these had suffered trauma. Medical staff in the department were only rarely able to make any diagnosis, and management of these patients took place on an empirical, symptomatic basis. Management could be improved by better education of medical students and doctors. Use of an algorithm may be appropriate.

Fatal disseminated intravascular coagulation complicating dental extraction

A case is reported of fatal disseminated intravascular coagulation occurring 8 h after routine extraction of wisdom teeth in a 24-year-old woman. Since all bacteriological specimens taken were sterile and no other precipitant was found, we believe this case represents an example of the generalised Shwartzman reaction to the local trauma of dental extraction leading to fatal initiation of the coagulation system.

Nonpharmacologic intervention to reduce blood pressure in older patients with mild hypertension

BACKGROUND

Although nonpharmacologic interventions are widely recommended in the therapy of high blood pressure in older adults, surprisingly little data exist to confirm the efficacy of these interventions in older persons.

METHODS

We conducted a randomized, controlled clinical trial in persons aged 60 to 85 years with a diastolic blood pressure of 85 to 100 mm Hg. The experimental arm was a nonpharmacologic intervention combining weight reduction, sodium restriction, and increased physical activity. The nonpharmacologic intervention consisted of eight weekly group and two individual sessions during the intensive phase, followed by four monthly group sessions during the maintenance phase. The control group received no treatment during the study. Blood pressure was assessed by certified technicians (blinded to group assignment) using random zero sphygmomanometers.

RESULTS

Of 56 participants randomized, 47 completed the entire 6-month trial (21 in the intervention group and 26 in the control group). Attendance at the intervention sessions was excellent. The intervention group lost more weight (-2.1 kg) over 6 months than the control group (+0.3 kg). Trends for decreasing 24-hour urine sodium excretion in both the intervention and control groups, with greater trend in the intervention group, were not statistically significant. The intervention group experienced more reduction in systolic and diastolic blood pressure than did the control group (mean differences between groups at 6 months, 4.2/4.9 mm Hg, respectively).

CONCLUSIONS

Our data indicate that a nonpharmacologic intervention will lower systolic and diastolic blood pressure levels in older people with borderline or mild elevations of diastolic blood pressure.