Characterizing hepatitis B virus infection in children in the Democratic Republic of Congo to inform elimination efforts.

Objective: Despite global reductions in hepatitis B virus (HBV) prevalence, an estimated 6.2 million children are infected, two-thirds of whom live in the WHO Africa region. We sought to characterize childhood HBV to inform elimination efforts in the Democratic Republic of Congo (DRC), one of the largest and most populous African countries. Methods: Using the most recent (2013-14) nationally representative Demographic and Health Survey in the DRC, we analyzed HBV surface antigen (HBsAg) on dried blood spots and associated survey data from children aged 6-59 months. We estimated HBsAg-positivity prevalence nationally, regionally, and by potential correlates of infection. We evaluated spatial variation in HBsAg-positivity prevalence, overall and by age, sex, and vaccination status. Findings: Using data from 5,679 children, we found national HBsAg-positivity prevalence was 1.3% (95% CI: 0.9%-1.7%), but ranged from 0.0% in DRC's capital city province, Kinshasa, to 5.6% in northwestern Sud-Ubangi Province. Prevalence among boys (1.8%, 95% CI: 1.2%-2.7%) was double that among girls (0.7%, 95%CI: 0.4%-1.3%). Tetanus antibody-negativity, rurality, and lower household wealth were also significantly associated with higher HBsAg-positivity prevalence. We observed no difference in prevalence by age. Children had higher HBsAg-positivity odds if living with ≥1 HBsAg-positive adult household member (OR: 2.3, 95%CI: 0.7-7.8), particularly an HBsAg-positive mother (OR: 7.2, 95%CI:1.6-32.2). Conclusion: In the largest national survey of HBV among children and household contacts in the DRC, we found that childhood HBV prevalence was 10-60 times the global target of 0.1%. We highlight specific regions and populations for further investigation and focused prevention efforts.

Kinetics of surfactant desorption at an air-solution interface.

The kinetics of re-equilibration of the anionic surfactant sodium dodecylbenzene sulfonate at the air-solution interface have been studied using neutron reflectivity. The experimental arrangement incorporates a novel flow cell in which the subphase can be exchanged (diluted) using a laminar flow while the surface region remains unaltered. The rate of the re-equilibration is relatively slow and occurs over many tens of minutes, which is comparable with the dilution time scale of approximately 10-30 min. A detailed mathematical model, in which the rate of the desorption is determined by transport through a near-surface diffusion layer into a diluted bulk solution below, is developed and provides a good description of the time-dependent adsorption data. A key parameter of the model is the ratio of the depth of the diffusion layer, H(c), to the depth of the fluid, H(f), and we find that this is related to the reduced Péclet number, Pe*, for the system, via H(c)/H(f) = C/Pe*(1/2). Although from a highly idealized experimental arrangement, the results provide an important insight into the "rinse mechanism", which is applicable to a wide variety of domestic and industrial circumstances.

Endoscopic resection of fibro-osseous lesions of the paranasal sinuses.

Fibro-osseous tumors, including osteomas, ossifying fibromas, and fibrous dysplasia, are not uncommon benign lesions arising in the paranasal sinuses. Conventional wisdom advocates resection when these lesions are symptomatic, or when they exhibit rapid growth. Traditionally, resection has been performed via a variety of open approaches. With the advent of sinonasal endoscopy in the mid 1980s, and subsequent advances in technology and surgical techniques, endoscopic management of some of these lesions is now feasible. To date, a search of the literature reveals only three case reports of osteomas resected with endoscopic guidance. We present a series of 10 symptomatic fibro-osseous lesions (nine osteomas and one fibrous dysplasia) occurring in nine patients in which endoscopic techniques were used. Nine ethmoid and frontal recess osteomas were resected transnasally and one sphenoid sinus fibrous dysplasia was resected using a transseptal transsphenoidal approach with endoscopic visualization. There were two anticipated CSF leaks, which were recognized and repaired at the time of surgery. There were no other complications and no tumor recurrence. All patients noted improvement in preoperative symptoms. We discuss patient selection, operative techniques and strategies, and the advantages and disadvantages of the endoscopic approach in the management of paranasal sinus fibro-osseous lesions.

Endoscopic resection of fibro-osseous lesions of the paranasal sinuses.

Fibro-osseous tumors, including osteomas, ossifying fibromas, and fibrous dysplasia, are not uncommon benign lesions arising in the paranasal sinuses. Conventional wisdom advocates resection when these lesions are symptomatic, or when they exhibit rapid growth. Traditionally, resection has been performed via a variety of open approaches. With the advent of sinonasal endoscopy in the mid 1980s, and subsequent advances in technology and surgical techniques, endoscopic management of some of these lesions is now feasible. To date, a search of the literature reveals only three case reports of osteomas resected with endoscopic guidance. We present a series of 10 symptomatic fibro-osseous lesions (nine osteomas and one fibrous dysplasia) occurring in nine patients in which endoscopic techniques were used. Seven ethmoid and frontal recess osteomas were resected transnasally and one sphenoid sinus fibrous dysplasia was resected using a transseptal transsphenoidal approach with the assistance of direct endoscopic visualization. There were two anticipated CSF leaks that were recognized and repaired at the time of surgery. There were no other complications and no tumor recurrence. All patients noted improvement in preoperative symptoms. We discuss patient selection, operative techniques and strategies, and the advantages and disadvantages of the endoscopic approach in the management of paranasal sinus fibro-osseous lesions.

Magnetic resonance cisternography and thin coronal computerized tomography in the evaluation of cerebrospinal fluid rhinorrhea.

In recent years cerebrospinal fluid (CSF) rhinorrhea has been managed successfully with transnasal endoscopic techniques. The most important and often most difficult step is the precise localization of the fistula. Computerized tomographic and radionuclide cisternography are two commonly used techniques for preoperative identification of the CSF fistula when it cannot be seen clearly with nasal endoscopy. Each of these requires a lumbar puncture, and the intrathecal placement of contrast material has been associated with transient neurotoxicities. Magnetic resonance cisternography (MRC) is a noncontrast study that does not require a lumbar puncture and has been used recently in the diagnosis of spontaneous and traumatic CSF leaks. Magnetic resonance cisternography utilizes a fast spin-echo sequence with fat suppression and video image reversal that highlights CSF. This allows precise localization of the fistula in both coronal and sagittal planes. Thin section coronal computed tomography (TCCT) is another noninvasive technique that can be helpful in localizing CSF leaks. The technique of MRC and TCCT and the results of 16 CSF leaks in 15 patients are reported. There was good correlation between MRC, TCCT, and intraoperative findings. Magnetic resonance cisternography and thin coronal computerized tomography appear to be accurate and complementary, noninvasive radiographic studies that should be considered in the evaluation CSF rhinorrhea.

Repair of mandibular fractures: plating vs. traditional techniques.

The treatment of mandibular fractures is a challenge for the otorhinolaryngologist-head and neck surgeon. Recent technologic advances have resulted in the development of rigid fixation techniques that hold promise for the early and optimal restoration of mandibular structure and function. The purpose of this article is to review the dental and orthopedic principles used in our mandibular fracture management, describe compression plating methodology, and discuss optimal techniques for its use. Results using rigid fixation procedures were compared with those using a variety of more traditional techniques in a retrospective analysis of 57 cases. The advantages, limitations, and indications for use of plating technology are discussed, and prevention of complications is emphasized.

Psychiatric nursing management of medication-free psychotic patients.

This article discusses how a team of psychiatric nurses manages acutely psychotic patients on a clinical research unit without the use of psychotropic medications. The article describes a schizophrenia research unit, identifies the behaviors of acutely psychotic patients, and provides examples of effective nursing interventions used on the unit. These interventions are grounded in principles of interpersonal psychiatric nursing practice and milieu therapy. The discussion is directed to psychiatric nurses and other health care professionals who are employed on research units.