Multidisciplinary Treatment in Patients with Craniofacial, Neurocognitive, and Neuromuscular Disorders with Obstructive Sleep Apnea: A Systematic Review of the Literature

Obstructive sleep apnea (OSA) is a respiratory disorder that has a high prevalence in patients with craniofacial, neurocognitive, and neuromuscular disorders. Currently, the treatments for this population are diverse and depend on the individual conditions of the patient and the severity of the case. However, there are no multidisciplinary dental treatment guidelines. The aim of the present study was to determine the multidisciplinary dental treatment alternatives in patients with craniofacial, neurocognitive, and neuromuscular disorders with a diagnosis of OSA through evidence-based medicine. A systematic review of the literature has been performed by searching scientific articles in the PubMed, Cochrane, Ovid, ScienceDirect and Scopus databases, through controlled and uncontrolled language. Articles were classified according to the level of evidence and grades of recommendation through the Scottish Intercollegiate Guidelines Network. A total of 19,439 references were identified, of which 15 articles met the predetermined requirements to be included in the investigation. The articles included for this systematic review showed that mandibular distraction osteogenesis and adenotonsilectomy are the first-choice therapies for craniofacial and neurocognitive disorders. However, for neuromuscular disorders, the findings reported were not enough to provide information about surgical or nonsurgical alternatives. Despite the reported high frequency of OSA in those children with craniofacial, neurocognitive, and neuromuscular disorders, the evidence on the surgical and nonsurgical therapeutic success for OSA in these patients is scarce. It is necessary to perform future studies to investigate successful therapies for OSA in children. [Pediatr Ann. 2024;53(2):e62-e69.].

Cut-off points of neck and waist circumference as predictors of obstructive sleep apnea in the Colombian population: a comparison with polysomnography

BACKGROUND

Neck circumference (NC) is a useful anthropometric measure for predicting obstructive sleep apnea (OSA). Ethnicity and sex also influence obesity phenotypes. NC cut-offs for defining OSA have not been established for the Latin American population.

OBJECTIVES

To evaluate NC, waist circumference (WC), and body mass index (BMI) as predictors of OSA in the Colombian population and to determine optimal cut-off points.

DESIGN AND SETTING

Diagnostic tests were conducted at the Javeriana University, Bogota.

METHODS

Adults from three cities in Colombia were included. NC, WC, and BMI were measured, and a polysomnogram provided the reference standard. The discrimination capacity and best cut-off points for diagnosing OSA were calculated.

RESULTS

964 patients were included (57.7% men; median age, 58 years) and 43.4% had OSA. The discrimination capacity of NC was similar for men and women (area under curve, AUC 0.63 versus 0.66, P = 0.39) but better for women under 60 years old (AUC 0.69 versus 0.57, P < 0.05). WC had better discrimination capacity for women (AUC 0.69 versus 0.57, P < 0.001). There were no significant differences in BMI. Optimal NC cut-off points were 36.5 cm for women (sensitivity [S]: 71.7%, specificity [E]: 55.3%) and 41 cm for men (S: 56%, E: 62%); and for WC, 97 cm for women (S: 65%, E: 69%) and 99 cm for men (S: 53%, E: 58%).

CONCLUSIONS

NC and WC have moderate discrimination capacities for diagnosing OSA. The cut-off values suggest differences between Latin- and North American as well as Asian populations.

Isoniazid preventive therapy completion in children under 5 years old who are contacts of tuberculosis cases in Lima, Peru: study protocol for an open-label, cluster-randomized superiority trial

BACKGROUND

Children < 5 years old in contact with TB cases are at high risk for developing severe and fatal forms of TB. Contact investigation, BCG vaccination, and isoniazid preventive therapy (IPT) are the most effective strategies to prevent TB among children. However, the implementation of IPT faces challenges at several stages of the cascade of care of TB infection among children, particularly those less than 5 years old. In Peru, a large proportion of children do not complete IPT, which highlights the need to design effective interventions that enhance preventive therapy adherence and completion. Although the body of evidence for such interventions has grown, interventions in medium TB incidence settings are lacking. This study aims to test the effectiveness, acceptability, and feasibility of an intervention package to increase information and motivation to complete IPT among children < 5 who have been prescribed IPT.

METHODS

An open-label, cluster-randomized superiority trial will be conducted in two districts in South Lima, Peru. Thirty health facilities will be randomized as clusters, 10 to the intervention and 20 to control (standard of care). We aim to recruit 10 children from different households in each cluster. Participants will be caretakers of children aged < 5 years old who initiated IPT. The intervention consists of educational material, and short message services (SMS) reminders and motivators. The primary outcomes will be the proportion of children who picked up > 90% of the 24 weeks of IPT (22 pick-ups) and the proportion of children who picked up the 24 weeks of IPT. The standard of care is a weekly pick-up with monthly check-ups in a health facility. Feasibility and acceptability of the intervention will be assessed through an interview with the caretaker.

DISCUSSION

Unfavorable outcomes of TB in young children, high effectiveness of IPT, and low rates of IPT completion highlight the need to enhance adherence and completion of IPT among children < 5 years old. Testing of a context-adapted intervention is needed to improve IPT completion rates and therefore TB prevention in young children.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03881228. Registered on March 19, 2019.

Cryptic Oral Microbiota: What Is Its Role as Obstructive Sleep Apnea-Related Periodontal Pathogens?

Periodontitis has been commonly linked to periodontopathogens categorized in Socransky's microbial complexes; however, there is a lack of knowledge regarding "other microorganisms" or "cryptic microorganisms", which are rarely thought of as significant oral pathogens and have been neither previously categorized nor connected to illnesses in the oral cavity. This study hypothesized that these cryptic microorganisms could contribute to the modulation of oral microbiota present in health or disease (periodontitis and/or obstructive sleep apnea (OSA) patients). For this purpose, the presence and correlation among these cultivable cryptic oral microorganisms were identified, and their possible role in both conditions was determined. Data from oral samples of individuals with or without periodontitis and with or without OSA were obtained from a previous study. Demographic data, clinical oral characteristics, and genera and species of cultivable cryptic oral microorganisms identified by MALDI-TOF were recorded. The data from 75 participants were analyzed to determine the relative frequencies of cultivable cryptic microorganisms' genera and species, and microbial clusters and correlations tests were performed. According to periodontal condition, dental-biofilm-induced gingivitis in reduced periodontium and stage III periodontitis were found to have the highest diversity of cryptic microorganism species. Based on the experimental condition, these findings showed that there are genera related to disease conditions and others related to healthy conditions, with species that could be related to different chronic diseases being highlighted as periodontitis and OSA comorbidities. The cryptic microorganisms within the oral microbiota of patients with periodontitis and OSA are present as potential pathogens, promoting the development of dysbiotic microbiota and the occurrence of chronic diseases, which have been previously proposed to be common risk factors for periodontitis and OSA. Understanding the function of possible pathogens in the oral microbiota will require more research.

Machine learning for atrial fibrillation risk prediction in patients with sleep apnea and coronary artery disease

Background

Patients with sleep apnea (SA) and coronary artery disease (CAD) are at higher risk of atrial fibrillation (AF) than the general population. Our objectives were: to evaluate the role of CAD and SA in determining AF risk through cluster and survival analysis, and to develop a risk model for predicting AF.

Methods

Electronic medical record (EMR) database from 22,302 individuals including 10,202 individuals with AF, CAD, and SA, and 12,100 individuals without these diseases were analyzed using K-means clustering technique; k-nearest neighbor (kNN) algorithm and survival analysis. Age, sex, and diseases developed for each individual during 9 years were used for cluster and survival analysis.

Results

The risk models for AF, CAD, and SA were identified with high accuracy and sensitivity (0.98). Cluster analysis showed that CAD and high blood pressure (HBP) are the most prevalent diseases in the AF group, HBP is the most prevalent disease in CAD; and HBP and CAD are the most prevalent diseases in the SA group. Survival analysis demonstrated that individuals with HBP, CAD, and SA had a 1.5-fold increased risk of developing AF [hazard ratio (HR): 1.49, 95% CI: 1.18-1.87, p = 0.0041; HR: 1.46, 95% CI: 1.09-1.96, p = 0.01; HR: 1.54, 95% CI: 1.22-1.94, p = 0.0039, respectively] and individuals with chronic kidney disease (CKD) developed AF approximately 50% earlier than patients without these comorbidities in a period of 7 years (HR: 3.36, 95% CI: 1.46-7.73, p = 0.0023). Comorbidities that contributed to develop AF earlier in females compared to males in the group of 50-64 years were HBP (HR: 3.75 95% CI: 1.08-13, p = 0.04) CAD and SA in the group of 60-75 years were (HR: 2.4 95% CI: 1.18-4.86, p = 0.02; HR: 2.51, 95% CI: 1.14-5.52, p = 0.02, respectively).

Conclusion

Machine learning based algorithms demonstrated that CAD, SA, HBP, and CKD are significant risk factors for developing AF in a Latin-American population.

Patients with obstructive sleep apnea can favor the predisposing factors of periodontitis by the presence of P. melaninogenica and C. albicans, increasing the severity of the periodontal disease

Objective

The aim of this study was to analyze the cultivable oral microbiota of patients with obstructive sleep apnea (OSA) and its association with the periodontal condition.

Methods

The epidemiology profile of patients and their clinical oral characteristics were determined. The microbiota was collected from saliva, subgingival plaque, and gingival sulcus of 93 patients classified into four groups according to the periodontal and clinical diagnosis: Group 1 (n = 25), healthy patients; Group 2 (n = 17), patients with periodontitis and without OSA; Group 3 (n = 19), patients with OSA and without periodontitis; and Group 4 (n = 32), patients with periodontitis and OSA. Microbiological samples were cultured, classified, characterized macroscopically and microscopically, and identified by MALDI-TOF-MS. The distribution of complexes and categories of microorganisms and correlations were established for inter- and intra-group of patients and statistically evaluated using the Spearman r test (p-value <0.5) and a multidimensional grouping analysis.

Result

There was no evidence between the severity of OSA and periodontitis (p = 0.2813). However, there is a relationship between the stage of periodontitis and OSA (p = 0.0157), with stage III periodontitis being the one with the highest presence in patients with severe OSA (prevalence of 75%; p = 0.0157), with more cases in men. The greatest distribution of the complexes and categories was found in oral samples of patients with periodontitis and OSA (Group 4 P-OSA); even Candida spp. were more prevalent in these patients. Periodontitis and OSA are associated with comorbidities and oral conditions, and the microorganisms of the orange and red complexes participate in this association. The formation of the dysbiotic biofilm was mainly related to the presence of these complexes in association with Candida spp.

Conclusion

Periodontopathogenic bacteria of the orange complex, such as Prevotella melaninogenica, and the yeast Candida albicans, altered the cultivable oral microbiota of patients with periodontitis and OSA in terms of diversity, possibly increasing the severity of periodontal disease. The link between yeasts and periodontopathogenic bacteria could help explain why people with severe OSA have such a high risk of stage III periodontitis. Antimicrobial approaches for treating periodontitis in individuals with OSA could be investigated in vitro using polymicrobial biofilms, according to our findings.

A Recurrent FAM83H Mutation in an Extended Colombian Family and Variable Craniofacial Phenotypes

Amelogenesis imperfecta (AI) is a collection of rare genetic disorders affecting the quantity and/or quality of the tooth enamel. AI can be classified into three major types according to the clinical phenotype: hypoplastic, hypocalcified, and hypomatured. Among them, the hypocalcified type shows the weakest physical properties, leaving rough and discolored enamel surfaces after tooth eruption. To date, mutations in the FAM83H gene are responsible for the autosomal-dominant hypocalcified AI. In this study, we recruited a four-generation Colombian family with hypocalcified AI and identified a recurrent nonsense mutation in the FAM83H gene (NM_198488.5:c.1289C>A, p.(Ser430 *)) by candidate gene sequencing. Cephalometric analyses revealed the anterior open bite that occurred in the proband is not correlated with the AI in this family.

Hypoxic Regulation of the Large-Conductance, Calcium and Voltage-Activated Potassium Channel, BK

Hypoxia is a condition characterized by a reduction of cellular oxygen levels derived from alterations in oxygen balance. Hypoxic events trigger changes in cell-signaling cascades, oxidative stress, activation of pro-inflammatory molecules, and growth factors, influencing the activity of various ion channel families and leading to diverse cardiovascular diseases such as myocardial infarction, ischemic stroke, and hypertension. The large-conductance, calcium and voltage-activated potassium channel (BK) has a central role in the mechanism of oxygen (O₂) sensing and its activity has been related to the hypoxic response. BK channels are ubiquitously expressed, and they are composed by the pore-forming α subunit and the regulatory subunits β (β1–β4), γ (γ1–γ4), and LINGO1. The modification of biophysical properties of BK channels by β subunits underly a myriad of physiological function of these proteins. Hypoxia induces tissue-specific modifications of BK channel α and β subunits expression. Moreover, hypoxia modifies channel activation kinetics and voltage and/or calcium dependence. The reported effects on the BK channel properties are associated with events such as the increase of reactive oxygen species (ROS) production, increases of intracellular Calcium ([Ca²⁺]_i), the regulation by Hypoxia-inducible factor 1α (HIF-1α), and the interaction with hemeproteins. Bronchial asthma, chronic obstructive pulmonary diseases (COPD), and obstructive sleep apnea (OSA), among others, can provoke hypoxia. Untreated OSA patients showed a decrease in BK-β1 subunit mRNA levels and high arterial tension. Treatment with continuous positive airway pressure (CPAP) upregulated β1 subunit mRNA level, decreased arterial pressures, and improved endothelial function coupled with a reduction in morbidity and mortality associated with OSA. These reports suggest that the BK channel has a role in the response involved in hypoxia-associated hypertension derived from OSA. Thus, this review aims to describe the mechanisms involved in the BK channel activation after a hypoxic stimulus and their relationship with disorders like OSA. A deep understanding of the molecular mechanism involved in hypoxic response may help in the therapeutic approaches to treat the pathological processes associated with diseases involving cellular hypoxia.

Sense of coherence and dental fear/dental anxiety: A systematic review and meta-analysis

AIM

The aim of this systematic review and meta-analysis was to evaluate the association between sense of coherence (SOC) and dental fear/dental anxiety.

METHODS

Computerized searches were performed in six databases. Gray literature and manual searches were also conducted. Study selection, risk of bias assessment, and meta-analyses were performed. The results of meta-analyses were reported in odds ratio (OR), mean difference (MD), and confidence interval (CI).

RESULTS

After removing duplicates, 131 references were retrieved and the full texts of 12 were evaluated. Nine references met the eligibility criteria and were included. The results of meta-analyses demonstrated that individuals with a weaker SOC had a score in the dental anxiety/dental fear scale 6.04 times higher than individuals with a stronger SOC (OR = 6.04, CI = 2.62-13.91). Individuals with no dental anxiety/dental fear had a mean score of the SOC scale higher than individuals with dental anxiety/dental fear (MD = 5.39, CI = 2.21-8.56). Sensitivity analysis demonstrated that the result of a higher mean score of the SOC scale among individuals with no dental anxiety/dental fear remained (MD = 7.38, CI = 3.79-10.98). Risk of bias ranged from low to high. The certainty of evidence was very low.

CONCLUSION

Individuals with stronger SOC have lower levels of dental fear/dental anxiety.

Clinical characteristics of vulnerable populations hospitalized and diagnosed with COVID-19 in Buenos Aires, Argentina

There is not in Argentina publications regarding the presentation of patients with COVID-19 requiring hospitalized and emergency care in vulnerable populations (lower incomes and less education tend at greater risk for poor health status and healthcare access), and it has few reports in developing countries. The objective is to determine whether in the care of vulnerable patients, to succeed against COVID-19, multiple public health tools and interventions will be needed to minimize morbidity and mortality. The study is a prospective cohort investigation of patients with lab-confirmed COVID-19, who required to any of the Health Centers response from April 8, 2020, to August 18, 2020. In Buenos Aires Metropolitan Area (AMBA), April 8, 2020 the virus was identified in patients hospitalized in the "Southeast Network" (SN), AMBA. SN covering an area of 661 square kilometers, with 1.8 million inhabitants residing in urban, and rural areas. A total of 14 health centers with different levels of care complexity provide care to patients in the region. The information of each patient with COVID-19 evaluated by SN, was incorporated in an Epidemiological Dashboard. The investigation was designed and reported with consideration of observational studies in epidemiology. We describe the hospitals presentation and care of persons who required SN response and were ultimately diagnosed with COVID-19. From April 8, 2020, to August 18, 2020, were included 1495 patients with lab-confirmed COVID-19 in SN. A total of 58% patients were men, and the mean age (SD) was 48.9 (15.59) years. Eighty one percent patients with pre-existing diseases, most frequent hypertension and diabetes, but hypertension, chronic lung disease, and cardiovascular disease presented higher risk. A total of 13% were hospitalized in Intensive Therapy Unit. The mortality of the cohort was 9.77%. Mortality was higher for patients aged 65 or more (OR 5.09), and for those had some pre-existing disease (OR 2.61). Our observations are consistent with reports demonstrating older persons, and those with comorbidities have the highest risk of mortality related to COVID-19. However, unlike other reports from developed or some developing countries, the mortality in our study is lower. This finding may be related to age of our cohort is younger than other published. Also, the health system was able to respond to the demand.

Variations in AXIN2 predict risk and prognosis of colorectal cancer

Objective

Colorectal cancer (CRC) and hypodontia are frequent and different diseases with common genes are involved in their etiology. The objective of this study was to identify the association between AXIN2 rs2240308 with hypodontia and CRC.

Patients and methods

This study consisted of 50 individuals with hypodontia, 50 individuals with CRC, and 155 healthy individuals from Colombia. SNP genotyping assays of rs2240308 were performed and family history of cancer in individuals with hypodontia was documented. In silico analysis was implemented to define the genomic profile of the AXIN2 gene associated with CRC. Multivariate analysis, chi square, odd ratio tests, and R software were used for statistical analysis.

Results

AXIN2 rs2240308 showed association with CRC (OR = 5.4 CI: 2.7–10.4; p < 0.001) and with other familial cancer in individuals with hypodontia (p < 0.005 OR = 1.75, 95% CI: 1.22–6.91). In silico analysis showed that variations in AXIN2 found in CRC patients, were more frequently in earlier stages of tumor and patients who carry variations in the AXIN2 gene have a worse prognosis (p < 0.05). The association between AXIN2 rs2240308 with hypodontia was not significant.

Conclusions

These results suggest that AXIN2 rs2240308 polymorphism is associated with CRC and AXIN2 could be a risk marker for predisposition and prognosis of CRC.

Dental Anomalies in Permanent Teeth Associated With Nonsyndromic Cleft Lip and Palate in a Group of Colombian Children

Objectives:

To assess the risk of dental anomaly presentation in permanent teeth in a group of Colombian children with nonsyndromic cleft lip and palate (NSCLP) and to determine the frequency of the anomalies according to the cleft type.

Methods:

An analytical matched case–control study was conducted with 210 controls and 210 patients with NSCLP. The patients were classified into 3 groups: complete right unilateral cleft lip and palate (RCLP), complete left unilateral cleft lip and palate (LCLP), and complete bilateral cleft lip and palate (BCLP). Univariate and multivariate Poisson regression models were used to analyze paired samples (Bonferroni adjustment, P ≤ .002).

Results:

A high risk of finding agenesis of the maxillary lateral incisors, supernumerary teeth, microdontia of the maxillary lateral incisors, and rotation of the maxillary central incisors adjacent to the cleft ( P < .0001) was observed in the patients with NSCLP. One or more dental anomalies were found in 98% of patients with BCLP, in 96% of those with LCLP, and in 87% of those with RCLP. Most of the anomalies were located on the cleft area. The incidence relative risk (IRR) of anomalies was highest in patients with BCLP (IRR: 10.5; 95% confidence interval [CI]: 6.76-16.3), followed by in those with LCLP (IRR: 8.51; 95% CI: 5.64-12.8).

Conclusions:

Most dental anomalies were found in the cleft area; this was expected because the cleft area was the most affected in the patients included in this study.

Association between obstructive sleep apnea and comorbidities with periodontal disease in adults

Background:

Several studies have reported an association between periodontal disease and obstructive sleep apnea (OSA). However, heterogeneity of results suggests that there is insufficient evidence to support this association.

Aims:

The objective of this study was to identify the association between periodontal disease and OSA in adults with different comorbidities.

Settings and Design:

One hundred and ninety-nine individuals (107 women and 92 men) underwent polysomnography with a mean age of 49.9 years were recruited.

Materials and Methods:

The presence of OSA, comorbidities, and periodontal disease was evaluated in each individual. Student's t-tests or Chi-square and ANOVA tests were used to determine the differences between groups.

Results:

The prevalence of periodontal disease was 62.3% and 34.1% for gingivitis. The results showed no statistically significant association between all groups of patients with OSA and non-OSA patients for gingivitis (P = 0.27) and for periodontitis (P = 0.312). However, statistically significant association was shown between periodontitis and mild OSA compared with the periodontitis and non-OSA referent (P = 0.041; odds ratio: 1.37 and 95% confidence interval 1.11–2.68). The analysis between OSA and comorbidities showed a statistically significant difference for patients with OSA and hypertension (P < 0.001) and for patients with OSA and hypertensive cardiomyopathy (P < 0.001) compared with healthy individuals. Periodontitis was more likely in men with severe OSA and with any of two comorbidities such as hypertension or hypertensive cardiomyopathy. Women with hypertension or hypertensive cardiomyopathy were more likely to have mild OSA, and these associations were statistically significant (P < 0.05).

Conclusions:

This study identified association between periodontitis and mild OSA and this association was more frequent in women with hypertension or hypertensive cardiomyopathy. Periodontitis was associated with severe OSA in men who showed any of two comorbidities such as hypertension or hypertensive cardiomyopathy.

Association of Cardiovascular Disease and Sleep Apnea at Different Altitudes

Otero, Liliana, Patricia Hidalgo, Rafael González, and Carlos A. Morillo. Association of cardiovascular disease and sleep apnea at different altitudes. High Alt Med Biol. 17:336-341, 2016.-We evaluated the prevalence of sleep apnea (SA) in patients with cardiovascular disease (CVD) at different altitudes. A total of 398 subjects with coronary artery disease (CAD), 144 subjects with atrial fibrillation (AF), and 292 controls (without CVD) were recruited in three cities at sea level, moderate altitude, and high altitude. All participants underwent polysomnography. Multinomial logistic regression, X², and Hosmer and Lemeshow tests were used to determine interactions among CVD, SA, and altitude. Men and women with CVD at high altitude had a higher risk for SA than men and women living at lower altitudes. The highest risk of SA was observed in men with AF and men with CAD living at high altitude. Obstructive SA (OSA) prevalence was significantly increased in CVD subjects living at high altitude (OR: 5.52; p < 0.0001). Central SA (CSA) was more frequent in subjects with CVD than control group (OR: 2.44; p < 0.021). OSA was the most frequent type of SA in subjects with CVD and overweight subjects, and in control individuals with obesity or being overweight. Significant differences in the prevalence of SA associated with altitude and gender were noted in subjects with CAD and AF.

Expression and Presence of OPG and RANKL mRNA and Protein in Human Periodontal Ligament with Orthodontic Force

OBJECTIVE

The objective of this study is to investigate the expression and concentration of ligand receptor activator of NFkB (RANKL) and osteoprotegerin (OPG) in human periodontal ligament (hPDL) with orthodontic forces of different magnitudes.

METHODS

Right premolars in 32 patients were loaded with 4oz or 7oz of orthodontic force for 7 days. Left first premolars were not loaded. After 7 days, premolars were extracted for treatment as indicated. OPG and RANKL mRNA expressions were measured by quantitative reverse transcription polymerase chain reaction (qRT-PCR), and ELISA was used to assess OPG and RANKL protein concentration in compression and tension sides of PDL. Data were subjected to analysis of variance and Tukey tests.

RESULTS

There was statistically significant difference in RANKL concentration on comparing control teeth with tension and compression sides of the experimental teeth (P < 0.0001). The expression of mRNA RANKL was increased in the tension and compression sides with 4oz (P < 0.0001). OPG did not show statistically significant association with any group. Changes in RANKL/OPG protein ratio in experimental and control groups showed statistically significant difference (P < 0.0001).

CONCLUSIONS

RANKL protein levels are elevated in hPDL loaded with orthodontic forces, suggesting that RANKL protein contributes to bone modeling in response to the initial placement of orthodontic force.

Time to initiation of multidrug-resistant tuberculosis treatment and its relation with outcome in a high incidence district in Lima, Peru

OBJECTIVE

To determine the time from diagnosis to start of multidrug resistant tuberculosis (MDR TB) treatment in Lima, Peru.

METHODS

We studied new smear-positive TB adults that were started on MDR TB treatment or that were switched to it between June 2008 and December 2011.

RESULTS

Time from the first positive smear to MDR-TB treatment was >30 days in 35% (13/37) of patients. Among the 27% (24/88) of patients that switched to MDR-TB treatment, time from the last dose of a drug-susceptible regimen was >30 days.

CONCLUSION

Start of and switching to MDR TB treatment is still delayed.

Charge separation in donor-acceptor spiro compounds at metal and metal oxide surfaces investigated by surface photovoltage

Molecules with donor (diphenylamine) and acceptor moieties (dicyano or cyanoacrylic acid moieties) were linked by fluorene or spirobisfluorene cores and the chain length has been changed by introducing a thiophene group between fluorene and diphenylamine. Four different kinds of fluorene and spirobisfluorene compounds were adsorbed from highly diluted solutions at ultra-thin nanoporous TiO2 (np-TiO2), Au and ITO surfaces. Charge separation has been investigated by surface photovoltage spectroscopy in the fixed capacitor and Kelvin probe arrangements in vacuum. Striking differences between the interaction of linking (dicyano or cyanoacrylic moieties) and different substrates were observed. Intra-molecular charge separation and electron injection have been distinguished and the directed adsorption of spiro compounds was deduced.

Endogenous neurogenesis after intracerebral hemorrhage

Currently, it is accepted that brain injury promotes endogenous neurogenesis in mammals, primarily in the subventricular zone (SVZ), and newborn cells can migrate to the injured area. We examined the pattern of endogenous neurogenesis in adult rats after intracerebral hemorrhage (ICH) that was caused by intrastrial administration of collagenase type IV. Our results showed that ICH induced strong endogenous neurogenesis between 72 hours and 7 days after injury, but that the majority of newborn cells did not survive longer than 3 weeks due to apoptosis-mediated cell death. Furthermore, endogenous neurogenesis remained into a small extent at least 1 year after ICH. Because of the growing interest in new strategies for brain regeneration, these data suggest endogenous neurogenesis and inhibiting apoptosis of newborn neuroblasts as potential strategies to improve the consequences of hemorrhagic stroke in humans.

Quality assessment of smear microscopy by stratified lot sampling of treatment follow-up slides

SETTING

Ten peripheral laboratories performing routine acid-fast bacilli (AFB) smear microscopy in Lima, Peru.

OBJECTIVES

To test whether external quality assessment (EQA) rechecking of AFB smears becomes more efficient with stratified lot sampling of treatment follow-up smears.

DESIGN

In 2 consecutive years, a stratified lot sample of 36 treatment follow-up slides and 24 diagnostic slides were randomly selected and blindly rechecked. A second controller determined the final result for discordant slides. Feedback was provided to laboratory technicians during supervisory visits.

RESULTS

More false-negative errors were found in the follow-up slides than in the tuberculosis suspect slides: 25 vs. 3. This represented a yield of 3.5% in 720 follow-up slides and only 0.6% in 480 diagnostic slides. Positive predictive values were high in both years. Respectively three and eight laboratories did not reach a relative sensitivity of >65% during the first and second year, and a clear improvement was seen in only one laboratory. Excessive workload seemed to preclude raising the level of routine performance.

CONCLUSIONS

EQA with stratified lot sampling of treatment follow-up slides proved very efficient and effective for identifying laboratories with substandard performance in a setting with low positivity rates in routine diagnostic smears.

Duration of cough, TB suspects' characteristics and service factors determine the yield of smear microscopy

OBJECTIVE

To determine the efficiency of routine tuberculosis (TB) case detection by examining sputum smear positivity for acid-fast bacilli in relation to duration of cough, characteristics of TB suspects examined and health service factors.

METHOD

We combined patient interviews with routine data from laboratory registers in 6 health care facilities in San Juan de Lurigancho district, Lima, Peru. A TB case was defined as a TB suspect with at least one positive sputum smear. We calculated adjusted odds ratios with 95% confidence intervals for the association between smear positivity and health service and patient's characteristics.

RESULTS

  Smear positivity was 7.3% (321/4376). Of the 4376 adults submitting sputa, 55.3% (2418) reported cough for <14 days. In this group, smear microscopy yielded 3.2% (78/2418) positive results vs. 12.4% (243/1958) in patients coughing for 14 or more days. Having cough for >2 weeks, being referred by health care staff, attending a secondary-level health care facility, male sex and age between 15 and 44 years were independent determinants of smear positivity.

CONCLUSIONS

Routine case detection yields a low proportion of smear-positive cases because of the inclusion of a high proportion of patients without cough or coughing for <2 weeks. Adherence to the national TB control programme guidelines on the selection of TB suspects would have a positive impact on the smear positivity rate, reduce laboratory costs and workload and possibly improve the reading quality of smear microscopy.

The effect and fate of antibiotics during the anaerobic digestion of pig manure

This work studies the inhibitory effects and fate of the antibiotics oxytetracycline (OTC) and chlortetracycline (CTC) during the anaerobic digestion of pig manure. Both substances were added together in batch assays at concentrations of 10, 50 and 100mgL(-1). Control assays only with antibiotics (abiotic) as well as without antibiotics (biotic) were also conducted. Methane production was reduced by 56%, 60% and 62% at OTC and CTC concentrations of 10, 50 and 100mgL(-1), respectively. The IC(50) level calculated from these experiments was estimated to be around 9mgL(-1), a significant value considering the reported concentrations of these compounds in pig manure samples (up to 136mgL(-1)). Strong adsorption to solid matter was observed, which increased the stability of both substances. Antibiotic degradation was thus much higher in control assays, without solids, than those determined from assays including inoculum and manure substrate.

Intralesional administration of allogeneic bone marrow stromal cells reduces functional deficits after intracerebral hemorrhage

When a severe neurological lesion occurs as a consequence of intracerebral bleeding, no effective treatment for improving the outcome is currently available. In the present study, intracerebral hemorrhage (ICH) was induced by stereotactic injection of 0.5 U of collagenase type IV in the striatum of adult Wistar rats, and three days later, intralesional administration of 2 x 10(6) allogeneic bone marrow stromal cells (BMSC) in saline (n:10), or saline only (n:10), was performed. In the following 30 days, functional outcome was evaluated in each animal by rotarod and the modified neurological severity score (mNSS) test. Progressive and functional improvement was observed in BMSC-transplanted rats compared with controls, together with morphological images suggesting that intracerebral administration of BMSC increases endogenous neurogenesis at the level of subventricular zone (SVZ). These findings suggest that local administration of allogeneic BMSC could be useful to reduce the neurological deficits caused by intracerebral hemorrhage.

A methodology for optimising feed composition for anaerobic co-digestion of agro-industrial wastes

An optimisation protocol for maximising methane production by anaerobic co-digestion of several wastes was carried out. A linear programming method was utilised to set up different blends aimed at maximising the total substrate biodegradation potential (L CH(4)/kg substrate) or the biokinetic potential (L CH(4)/kg substrate d). In order to validate the process, three agro-industrial wastes were considered: pig manure, tuna fish waste and biodiesel waste, and the results obtained were validated by experimental studies in discontinuous assays. The highest biodegradation potential (321 L CH(4)/kg COD) was reached with a mixture composed of 84% pig manure, 5% fish waste and 11% biodiesel waste, while the highest methane production rate (16.4 L CH(4)/kg COD d) was obtained by a mixture containing 88% pig manure, 4% fish waste and 8% biodiesel waste. Linear programming was proved to be a powerful, useful and easy-to-use tool to estimate methane production in co-digestion units where different substrates can be fed.

Inheritance of craniofacial features in Colombian families with class III malocclusion

Introduction

The inheritance of class III malocclusion has been well documented, but the inheritance of craniofacial structures in Colombian families with this malocclusion has been not yet reported.

Patients and methods

The study sample of 25 families comprised 186 untreated orthodontic individuals from 8 to 60 years old. Pedigrees were drawn using Cyrillic software. Complete family histories for each proband were ascertained and the affection status of relatives was confirmed by lateral cephalograms and facial and dental photographs. Analysis of variance and odds ratio test for each parameter was performed to estimate inheritance from parents to offspring and to determine similar phenotypic features in relatives.

Results

The analysis of the pedigrees suggests autosomal dominant inheritance. The craniofacial characteristics that showed more resemblance between parents and offspring were middle facial height, shorter anterior cranial base and mandibular prognathism. In contrast the protrusion of upper lip and maxillary retrusion were the phenotypic features that contributed to class III in the majority of families.

Conclusion

Knowledge of the inheritance of craniofacial phenotypes in class III malocclusion will enable the design of new therapies to treat this malocclusion.

Ozonation strategies to reduce sludge production of a seafood industry WWTP

In this work, several alternatives related to the application of ozone in different streams of a seafood industry WWTP were evaluated to minimize the production of waste sludge. The WWTP was composed of two coagulation-flocculation units and a biological unit and generated around of 6550 kg/d of sludge. Ozone was applied to sludge coming from flotation units (110 g TSS/L) at doses up to 0.03 g O(3)/g TSS during batch tests, no solids solubilization being observed. Ozone doses ranging from 0.007 to 0.02 g O(3)/g TSS were also applied to the raw wastewater in a bubble column reaching a 6.8% of TSS removal for the highest ozone dose. Finally, the effect of the pre-ozonation (0.05 g O(3)/g TSS) of wastewater coming from the first flotation unit was tested in two activated sludge systems during 70 days. Ozonation caused a reduction of the observed yield coefficient of biomass from 0.14 to 0.07g TSS/g COD(Tremoved) and a slight improvement of COD removal efficiencies. On the basis of the capacity for ozone production available in the industry, a maximum reduction of sludge generated by the WWTP of 7.5% could be expected.

Observation of the suppression of the flux of cosmic rays above 4 x 10 (19) eV

The energy spectrum of cosmic rays above 2.5 x 10;{18} eV, derived from 20,000 events recorded at the Pierre Auger Observatory, is described. The spectral index gamma of the particle flux, J proportional, variantE;{-gamma}, at energies between 4 x 10;{18} eV and 4 x 10;{19} eV is 2.69+/-0.02(stat)+/-0.06(syst), steepening to 4.2+/-0.4(stat)+/-0.06(syst) at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz'min.

Upper limit on the diffuse flux of ultrahigh energy tau neutrinos from the Pierre Auger Observatory

The surface detector array of the Pierre Auger Observatory is sensitive to Earth-skimming tau neutrinos that interact in Earth's crust. Tau leptons from nu(tau) charged-current interactions can emerge and decay in the atmosphere to produce a nearly horizontal shower with a significant electromagnetic component. The data collected between 1 January 2004 and 31 August 2007 are used to place an upper limit on the diffuse flux of nu(tau) at EeV energies. Assuming an E(nu)(-2) differential energy spectrum the limit set at 90% C.L. is E(nu)(2)dN(nu)(tau)/dE(nu)<1.3 x 10(-7) GeV cm(-2) s(-1) sr(-1) in the energy range 2 x 10(17) eV< E(nu)< 2 x 10(19) eV.

Could clinical audit improve the diagnosis of pulmonary tuberculosis in Cuba, Peru and Bolivia?

OBJECTIVES

To assess the effectiveness of clinical audit in improving the quality of diagnostic care provided to patients suspected of tuberculosis; and to understand the contextual factors which impede or facilitate its success.

METHODS

Twenty-six health centres in Cuba, Peru and Bolivia were recruited. Clinical audit was introduced to improve the diagnostic care for patients attending with suspected TB. Standards were based on the WHO and TB programme guidelines relating to the appropriate use of microscopy, culture and radiological investigations. At least two audit cycles were completed over 2 years. Improvement was determined by comparing the performance between two six-month periods pre- and post-intervention. Qualitative methods were used to ascertain facilitating and limiting contextual factors influencing change among healthcare professionals' clinical behaviour after the introduction of clinical audit.

RESULTS

We found a significant improvement in 11 of 13 criteria in Cuba, in 2 of 6 criteria in Bolivia and in 2 of 5 criteria in Peru. Twelve out of 24 of the audit criteria in all three countries reached the agreed standards. Barriers to quality improvement included conflicting objectives for clinicians and TB programmes, poor coordination within the health system and patients' attitudes towards illness.

CONCLUSIONS

Clinical audit may drive improvements in the quality of clinical care in resource-poor settings. It is likely to be more effective if integrated within and supported by the local TB programmes. We recommend developing and evaluating an integrated model of quality improvement including clinical audit.

Association of MSX1 with nonsyndromic cleft lip and palate in a Colombian population

OBJECTIVE

To evaluate the association between MSX1 CA polymorphism and nonsyndromic cleft lip with or without cleft palate (CL+/-P) in a group of patients from Operation Smile Colombia.

DESIGN

Four alleles from MSX1 CA microsatellite sequence were analyzed. Polymerase chain reaction was carried out. The amplifications were performed by Short Tandem Repeats (STRs) in ABI PRISM 310 genetic analyzer. Chi-square and odds ratio tests were used to determine the association between genotype frequencies and the risk to the cleft lip/palate in a Colombian group population.

SETTING

Operation Smile Colombia.

PARTICIPANTS

Ninety-four affected patients (49 men and 45 women with CL+/-P) and 93 control individuals (43 men and 50 women).

RESULTS

A significant statistical difference (p<.0106) was found between the patients who carried allele 3 and CL+/-P. In addition, allele 4 (heterozygous and homozygous form) was the most frequent in CL+/-P (74%) patients and in the control group (82%).

CONCLUSIONS

These findings show a positive association between the MSX1 CA polymorphism and CL+/-P in a Colombian group population.