Applicability of lung ultrasound in COVID-19 diagnosis and evaluation of the disease progression: A systematic review.

INTRODUCTION: The COVID-19 pandemic originated in China and within about 4 months affected individuals all over the world. One of the limitations to the management of the COVID-19 is the diagnostic imaging to evaluate lung impairment and the patients' clinical evolution, mainly, in more severe cases that require admission into the intensive care unit. Among image examinations, lung ultrasound (LU) might be a useful tool to employ in the treatment of such patients. METHODS: A survey was carried out on PubMed to locate studies using the descriptors: ((Lung ultrasound OR ultrasound OR lung ultrasonography OR lung US) AND (coronavirus disease-19 OR coronavirus disease OR corona virus OR COVID-19 OR COVID19 OR SARS-CoV-2)). The period covered by the search was November 2019 to October 2020 and the papers selected reported LU in COVID-19. RESULTS: Forty-three studies were selected to produce this systematic review. The main LU findings referred to the presence of focal, multifocal and/or confluent B lines and the presence of pleural irregularities. CONCLUSIONS: The use of LU in the evaluation of patients with COVID-19 should be encouraged due to its intrinsic characteristics; a low cost, radiation free, practical method, with easy to sanitize equipment, which facilitates structural evaluation of lung damage caused by SARS-CoV-2. With the increase in the number of studies and the use of ultrasound scans, LU has been shown as a useful tool to evaluate progression, therapeutic response and follow-up of pulmonary disease in the patients with COVID-19.

A negative screening of rare genetic variants in the ADIPOQ and STATH genes in cystic fibrosis.

BACKGROUND: The phenotypic variability in cystic fibrosis (CF) is widely recognized and modulated by environmental and genetic factors, including CFTR pathogenic variants and modifier genes genetic variants. In this context, determining the presence of variants in genes involved in immune response may allow a better understanding of CF variability, mainly in lung disease. Thus, ADIPOQ and STATH genes were selected and the analysis of exons and exon/intron junctions was performed for the determination of variations in its sequence, to determine the possible genetic modulation. METHODS: A total of 49 patients with CF, diagnosed for showing abnormal [chloride] levels in the sweat test, and identification of two pathogenic variants in CFTR categorized as class I and II were included. Genetic sequencing was performed for the identification of variants in the modifier genes. RESULTS: In our analysis, there was absence of rare genetic variants in STATH and ADIPOQ genes associated with the clinical variability. Thus, we are not able to establish an association between the disease severity and rare genetic variants in STATH and ADIPOQ genes, considering exons and exon/intron junctions. CONCLUSIONS: Considering the negative screening for rare genetic variants in ADIPOQ and STATH genes, it may be concluded that these genes are not associated with phenotypic modulation of CF in our population. To understand the modifier genes and its action at CF variability it is essential to promote a better overview of the disease. Also, negative reports can help to direct new studies without the use of unnecessary financial support.

Suicide risk around the world: a meta-analysis of longitudinal studies.

PURPOSE: Suicidal thoughts and behaviors (STBs) have been a persistent problem worldwide. Identifying risk factors for STBs across distinct areas of the world may help predict who or where requires the greatest attention. However, risk factors for STBs are infrequently explored cross-nationally. The present study examined whether psychopathology prospectively predicts STBs across different areas of the world, and whether certain country-level factors moderate the degree of risk conferred. METHODS: We conducted a meta-analysis of 71 longitudinal studies from 30 different countries that featured psychopathology-related variables predicting STB outcomes. Meta-regression was used to evaluate whether the following country-level factors modified risk: geographic region, income level, and degree of mental health structural stigma. RESULTS: Over 90% of studies had been conducted in North America and Europe. When assessed by country income level, it was found that only one longitudinal study on psychopathology and STB was conducted outside of a high-income country. Moreover, less than 10% of studies were conducted in high structural stigma contexts. Meta-regression findings revealed that the variation in risk effect sizes across studies was not explained by models including country-level factors. CONCLUSIONS: Our findings show critical underrepresentation of low- and middle-income countries, which account for a large proportion of global suicide deaths. This reveals a need to broaden the scope of longitudinal research on STB risk, such that countries across more regions, income levels, and degrees of structural stigma are fully accounted for. Such lines of research will improve generalizability of findings, and more precisely inform prevention efforts worldwide.

Correlation between parameters of volumetric capnography and spirometry during a submaximal exercise protocol on a treadmill in patients with cystic fibrosis and healthy controls.

INTRODUCTION: Spirometry is the most frequently used test to evaluate the progression of lung damage in cystic fibrosis (CF). However, there has been low sensitivity in detecting early lung changes. In this context, our objective was to identify the correlation between parameters of volumetric capnography (VCap) and spirometric parameters during a submaximal treadmill exercise test. METHODS: A cross-sectional and controlled study which included 64 patients with CF (CFG) and 64 healthy control subjects (CG) was performed. The CFG was from a university hospital and the CG from local schools. All participants underwent spirometry and VCap before, during and after the submaximal treadmill exercise test. The main variable analyzed by VCap was the slope of phase 3 (slope 3), which indicates the [exhaled carbon dioxide] at the end of expiration, and expresses the heterogeneity of gas emptying in pulmonary periphery. The correlation analysis between spirometry and VCap was conducted using the Spearman correlation test, considering α=0.05. RESULTS: The indices analyzed by VCap showed correlation with parameters of VCap. Slope 3 showed an inverse correlation with forced expiratory volume in the first second of forced vital capacity (FEV1) in both groups and at all moments of the submaximal treadmill exercise test. Forced vital capacity (FVC) and FEV1/FVC ratio showed an inverse correlation with slope 3 only for CFG. Values of slope 3 corrected by the spontaneous tidal volume (VT) and end-tidal carbon dioxide tension (PetCO2) showed results similar to slope 3 analyzed separately. CONCLUSION: Parameters of VCap such as slope 3, slope 3/VT and slope 3/PetCO2 correlated with sensitive variables of spirometry such as FEV1, FVC and FEV1/FVC ratio. For the evaluated variables, there was consistency in the correlation between the two tests, which may indicate the impact of CF on pulmonary physiology.

Association between oxygenation and ventilation indices with the time on invasive mechanical ventilation in infants.

BACKGROUND: Invasive mechanical ventilation (IMV) is a common practice in pediatric intensive care unit (PICU). However, the role of oxygenation (OI) and ventilation (VI) indices regarding the time on IMV has not been fully understood. BASIC PROCEDURES: The study was conducted with infants up to 24 months of age, hospitalized in PICU for two consecutive years. The values of ventilatory parameters, OI, VI, and blood gas of infants, collected in the first seven days in IMV, were associated with the time on IMV. IMV was classified into: short (≤seven days) and long time (>seven days). The comparison was made from the first to the seventh day. Alpha=0.05. MAIN FINDINGS: Of 142 infants [mean age=7.51±6.33 months], 59 (41.5%) remained on IMV for a short time and 83 (58.5%) for a long time. Differences in PaO2 values were found on the second day, and PaO2/FiO2 ratio on the second, third and fourth days, with higher values in the short-term IMV. For FiO2 from the second to the fifth day; Pinsp from the first to the seventh day; PEEP from the second to the sixth day; mechanical respiratory frequency from the second to the seventh day, PaCO2 on the second day; Paw from the first to the seventh day, OI from the second to the sixth day, and VI from the first to the seventh day, the values were higher in the long-term IMV. CONCLUSIONS: The OI and VI can be considered as potential predictors of long-term IMV, along with other markers obtained during the IMV.

Psychosis as a risk factor for suicidal thoughts and behaviors: a meta-analysis of longitudinal studies.

BACKGROUND: Research has long noted higher prevalence rates of suicidal thoughts and behaviors among individuals with psychotic symptoms. Major theories have proposed several explanations to account for this association. Given the differences in the literature regarding the operationalization of psychosis and sample characteristics, a quantitative review is needed to determine to what extent and how psychosis confers risk for suicidality. METHODS: We searched PsycInfo, PubMed, and GoogleScholar for studies published before 1 January 2016. To be included in the analysis, studies must have used at least one psychosis-related factor to longitudinally predict suicide ideation, attempt, or death. The initial search yielded 2541 studies. Fifty studies were retained for analysis, yielding 128 statistical tests. RESULTS: Suicide death was the most commonly studied outcome (43.0%), followed by attempt (39.1%) and ideation (18.0%). The median follow-up length was 7.5 years. Overall, psychosis significantly conferred risk across three outcomes, with weighted mean ORs of 1.70 (1.39-2.08) for ideation, 1.36 (1.25-1.48) for attempt, and 1.40 (1.14-1.72) for death. Detailed analyses indicated that positive symptoms consistently conferred risk across outcomes; negative symptoms were not significantly associated with ideation, and were protective against death. Some small moderator effects were detected for sample characteristics. CONCLUSIONS: Psychosis is a significant risk factor for suicide ideation, attempt, and death. The finding that positive symptoms increased suicide risk and negative symptoms seemed to decrease risk sheds light on the potential mechanisms for the association between psychosis and suicidality. We note several limitations of the literature and offer suggestions for future directions.

Impulse oscillometry, spirometry, and passive smoking in healthy children and adolescents.

OBJECTIVE: To identify changes in the forced and quiet breathing parameters of lung function in healthy children and adolescents exposed to passive smoking (PS). METHOD: Comparative cross-sectional study. Healthy schoolchildren aged 6 to 14 years. We collected anthropometric data, lung function parameters using spirometry (forced breathing), and quiet breathing parameters using impulse oscillometry. The sample was divided into two groups according to exposure to PS: passive smoking group (PSG) and non-passive smoking group (NPSG). For the statistical analysis, the Shapiro-Wilk test was used to verify data normality and the T-test or Mann-Whitney test to compare spirometric and oscillometric parameters between groups (p≤0.05). MAIN FINDINGS: The study included 78 children and adolescents, with 14 boys and 25 girls in each group. There were differences in the mean values for peak expiratory flow (p=0.01). There were no significant differences between the groups in values for z-score and lower limit of normal. The PSG had higher mean absolute values for reactance area (X5=0.05) and significant percentage of predicted values for the following impulse oscillometry parameters: central airway resistance (R20%, p=0.03) and for the indicators of presence of airway obstruction (Fres%, p=0.01; X5%=0.01% and AX%, p=0.01). CONCLUSION: Children and adolescents exposed to PS had lower values for the spirometric variables and higher values for the oscillometric variables, indicating changes in forced and quiet parameters of lung function compared to the NPSG.

Physical performance, quality of life and sexual satisfaction evaluation in adults with cystic fibrosis: An unexplored correlation.

OBJECTIVE: Quality of life (QOL), sexual satisfaction (SS) and physical performance have been assessed in the management of numerous chronic diseases. METHODS: In this study, the following tests and surveys were applied: (i) QOL questionnaire [Cystic Fibrosis Questionnaire (CFQ)]; (ii) SS questionnaire (SSQ) [female sexual quotient (FSQ) and male sexual quotient (MSQ)]; (iii) 6-minute walk test (6MWT). Spearman's correlation was used for comparison between the data; the Mann-Whitney test was applied to analyze the difference between genders. A total of 52 adult patients with CF were included in this study. RESULTS: There was a positive correlation between CFQ domains and SSQ questions. The CFQ showed a positive correlation with peripheral oxygen saturation of hemoglobin (SpO2) and the distance walked in the 6MWT, and a negative correlation with the Borg scale. The SSQ showed positive correlation with the distance walked and a negative correlation with the Borg scale. For some markers evaluated in the 6MWT, there was sometimes association with the evaluated domains and questions. Male patients showed better scores in the emotional CFQ domain, better performance in SSQ and physical performance. CONCLUSIONS: There was a correlation between CFQ, SSQ and 6MWT in CF. Finally; we believe that QOL surveys should assess the domain "sexuality" as well as physical performance tests.

Biological risk factors for suicidal behaviors: a meta-analysis.

Prior studies have proposed a wide range of potential biological risk factors for future suicidal behaviors. Although strong evidence exists for biological correlates of suicidal behaviors, it remains unclear if these correlates are also risk factors for suicidal behaviors. We performed a meta-analysis to integrate the existing literature on biological risk factors for suicidal behaviors and to determine their statistical significance. We conducted a systematic search of PubMed, PsycInfo and Google Scholar for studies that used a biological factor to predict either suicide attempt or death by suicide. Inclusion criteria included studies with at least one longitudinal analysis using a biological factor to predict either of these outcomes in any population through 2015. From an initial screen of 2541 studies we identified 94 cases. Random effects models were used for both meta-analyses and meta-regression. The combined effect of biological factors produced statistically significant but relatively weak prediction of suicide attempts (weighted mean odds ratio (wOR)=1.41; CI: 1.09-1.81) and suicide death (wOR=1.28; CI: 1.13-1.45). After accounting for publication bias, prediction was nonsignificant for both suicide attempts and suicide death. Only two factors remained significant after accounting for publication bias-cytokines (wOR=2.87; CI: 1.40-5.93) and low levels of fish oil nutrients (wOR=1.09; CI: 1.01-1.19). Our meta-analysis revealed that currently known biological factors are weak predictors of future suicidal behaviors. This conclusion should be interpreted within the context of the limitations of the existing literature, including long follow-up intervals and a lack of tests of interactions with other risk factors. Future studies addressing these limitations may more effectively test for potential biological risk factors.

Self-injurious thoughts and behaviors as risk factors for future suicide ideation, attempts, and death: a meta-analysis of longitudinal studies.

BACKGROUND: A history of self-injurious thoughts and behaviors (SITBs) is consistently cited as one of the strongest predictors of future suicidal behavior. However, stark discrepancies in the literature raise questions about the true magnitude of these associations. The objective of this study is to examine the magnitude and clinical utility of the associations between SITBs and subsequent suicide ideation, attempts, and death. METHOD: We searched PubMed, PsycInfo, and Google Scholar for papers published through December 2014. Inclusion required that studies include at least one longitudinal analysis predicting suicide ideation, attempts, or death using any SITB variable. We identified 2179 longitudinal studies; 172 met inclusion criteria. RESULTS: The most common outcome was suicide attempt (47.80%), followed by death (40.50%) and ideation (11.60%). Median follow-up was 52 months (mean = 82.52, s.d. = 102.29). Overall prediction was weak, with weighted mean odds ratios (ORs) of 2.07 [95% confidence interval (CI) 1.76-2.43] for ideation, 2.14 (95% CI 2.00-2.30) for attempts, and 1.54 (95% CI 1.39-1.71) for death. Adjusting for publication bias further reduced estimates. Diagnostic accuracy analyses indicated acceptable specificity (86-87%) and poor sensitivity (10-26%), with areas under the curve marginally above chance (0.60-0.62). Most risk factors generated OR estimates of <2.0 and no risk factor exceeded 4.5. Effects were consistent regardless of sample severity, sample age groups, or follow-up length. CONCLUSIONS: Prior SITBs confer risk for later suicidal thoughts and behaviors. However, they only provide a marginal improvement in diagnostic accuracy above chance. Addressing gaps in study design, assessment, and underlying mechanisms may prove useful in improving prediction and prevention of suicidal thoughts and behaviors.

ZRF1 controls oncogene-induced senescence through the INK4-ARF locus.

The reactivation of the INK4-ARF locus, which is epigenetically repressed by Polycomb proteins in healthy cells, is a hallmark of senescence. One mechanism of reactivating Polycomb-silenced genes is mediated by the epigenetic factor ZRF1, which associates with ubiquitinated histone H2A. We show that cells undergoing senescence following oncogenic Ras expression have increased ZRF1 levels, and that this binds to the p15INK4b, ARF and p16INK4a promoters. Furthermore, ZRF1 depletion in oncogenic Ras-expressing cells restores proliferation by preventing Arf and p16Ink4a expression, consequently bypassing senescence. Thus, ZRF1 regulates the INK4-ARF locus during cellular proliferation and senescence, and alterations in ZRF1 may contribute to tumorigenesis.

Volumetric capnography for the evaluation of pulmonary disease in adult patients with cystic fibrosis and noncystic fibrosis bronchiectasis.

This study was designed to use volumetric capnography to evaluate the breathing pattern and ventilation inhomogeneities in patients with chronic sputum production and bronchiectasis and to correlate the phase 3 slope of the capnographic curve to spirometric measurements. Twenty-four patients with cystic fibrosis (CF) and 21 patients with noncystic fibrosis idiopathic bronchiectasis (BC) were serially enrolled. The diagnosis of cystic fibrosis was based on the finding of at least two abnormal sweat chloride concentrations (iontophoresis sweat test). The diagnosis of bronchiectasis was made when the patient had a complaint of chronic sputum production and compatible findings at high-resolution computed tomography (HRCT) scan of the thorax. Spirometric tests and volumetric capnography were performed. The 114 subjects of the control group for capnographic variables were nonsmoker volunteers, who had no respiratory symptoms whatsoever and no past or present history of lung disease. Compared with controls, patients in CF group had lower SpO(2) (P < 0.0001), higher respiratory rates (RR) (P < 0.0001), smaller expiratory volumes normalized for weight (V(E)/kg) (P < 0.028), smaller expiratory times (Te) (P < 0.0001), and greater phase 3 Slopes normalized for tidal volume (P3Slp/V(E)) (P < 0.0001). Compared with controls, patients in the BC group had lower SpO(2) (P < 0.0001), higher RR (P < 0.004), smaller V(E)/kg (P < 0.04), smaller Te (P < 0.007), greater P3Slp/V(E) (P < 0.0001), and smaller VCO(2) (P < 0.0002). The pooled data from the two patient groups compared with controls showed that the patients had lower SpO(2) (P < 0.0001), higher RR (P < 0.0001), smaller V(E)/kg (P < 0.05), smaller Te (P < 0.0001), greater P3Slp/V(E) (P < 0.0001), and smaller VCO(2) (P < 0.0003). All of the capnographic and spirometric variables evaluated showed no significant differences between CF and BC patients. Spirometric data in this study reveals that the patients had obstructive defects with concomitant low vital capacities and both groups had very similar abnormalities. The capnographic variables in the patient group suggest a restrictive respiratory pattern (greater respiratory rates, smaller expiratory times and expiratory volumes, normal peak expiratory flows). Both groups of patients showed increased phase III slopes compared with controls, which probably indicates the presence of diffuse disease of small airways in both conditions leading to inhomogeneities of ventilation.

Oral magnesium supplementation in asthmatic children: a double-blind randomized placebo-controlled trial.

OBJECTIVE: To investigate the long-term effect of oral magnesium supplementation on clinical symptoms, bronchial reactivity, lung function and allergen-induced skin responses in children and adolescents with moderate persistent asthma. DESIGN: A double-blind randomized parallel placebo-controlled study. SETTING AND SUBJECTS: The patients were recruited from the Pediatric Outpatient Clinic, Division of Pulmonology, Allergy and Immunology, and followed at the Center for Investigation in Pediatrics at State University of Campinas Hospital, Brazil. Thirty-seven out of 72 patients met the study criteria. There were no dropouts. INTERVENTION: The 37 patients (aged 7-19 years, 19 males) were randomized in two groups: magnesium (n=18, 300 mg/day) and placebo (n=19), during 2 months. Both patient groups received inhaled fluticasone (250 microg twice a day) and salbutamol as needed. The primary outcome was bronchial reactivity evaluated with methacholine challenge test (PC20). RESULTS: After a follow-up of 2 months, the methacholine PC20 for testing bronchial reactivity has augmented significantly in the magnesium group only. The skin responses to recognized antigens have also decreased in patients treated with magnesium. The forced vital capacity (FVC), the forced expiratory volume at first second (FEV1), the forced expiratory flow at 25-75 and the FEV1/FVC ratio were similar in both groups. The magnesium group presented fewer asthma exacerbations and used less salbutamol compared to the placebo group. CONCLUSIONS: Oral magnesium supplementation helped to reduce bronchial reactivity to methacholine, to diminish their allergen-induced skin responses and to provide better symptom control in pediatric patients with moderate persistent asthma treated with inhaled fluticasone.

Are immunoglobulin E levels associated with early wheezing? A prospective study in Brazilian infants.

The relationship between wheezing or asthma and serum immunoglobulin (Ig)E levels in early life is unclear. The aim of this study was to follow-up the IgE immune response in infants that did, or did not, develop recurrent wheezing during their first year of life. One-hundred and two randomised term neonates were included, in which IgE levels were quantified in cord blood samples, at 3, 6, 9 and 12 months of age. Specific IgE levels for food and inhalant allergens and the skin-prick test for inhalant allergens were also assessed at 6 and 12 months. During clinical follow-up, 32 (31%) infants presented with two or more wheezing episodes, while 70 (69%) had no wheezing. Total IgE levels were significantly higher up to 12 months in wheezing infants when compared to nonwheezing group. At 12 months, the specific IgE levels to cow's milk, egg white and mites were higher in infants with recurrent wheezing. There was no influence of family history for atopy on IgE levels. The skin-prick tests were positive in 14% and 23% in wheezing infants at 6 and 12 months, respectively. These results indicate an early allergic sensitisation in wheezing infants, suggesting an altered immunoregulatory T-cell role in immunoglobulin E production.

[Effects of cisapride and chest physical therapy on the gastroesophageal reflux of wheezing babies based on scintigraphy] / Efeito da cisaprida e da fisioterapia respiratória sobre o refluxo gastroesofágico de lactentes chiadores segundo avaliação cintilográfica.

OBJECTIVE: To evaluate the effect of cisapride and chest physical therapy on the gastroesophageal reflux of wheezing babies. METHODS: We prospectively assessed the presence of technetium ((99)Tc) in the upper, middle, and lower esophagus of 25 wheezing babies (13 with GERD and 12 without GERD) using scintigraphy. Both groups underwent clinical investigation, including laboratory, X-ray and scintigraphy tests, for the etiology of the wheezing baby syndrome (WBS) and GERD. Expiratory Flow Acceleration (EFA) was performed before and after treatment with cisapride. The total time of GER episodes was accounted for each portion of the esophagus during scintigraphy and during EFA. RESULTS: Cisapride significantly reduced the total reflux time in the upper esophagus (P<0.05), but showed no influence during EFA. After cisapride therapy, EFA increased the total reflux time in the upper and medium esophagus; however, no statistical significance was found. Infants with GERD presented a shorter total reflux time in the distal esophagus (P<0.05) during EFA. After cisapride treatment, no statistical significance was found. Infants without GERD also presented reduced total reflux time in the distal esophagus during EFA (P<0.05). Those with GERD had increased total reflux time in the distal esophagus (P<0.05) before and after cisapride treatment during EFA and scintigraphy. CONCLUSIONS: Cisapride was effective in reducing the total reflux time, mainly in the upper esophagus. EFA apparently increased the number of episodes of GER, without achieving statistical significance. Further studies are necessary to investigate the effects of chest physical therapy according to body positions.

Genetic and environmental influences on atopic immune response in early life.

The purpose of our study was to carry out a prospective follow-up of 114 newborns at term (including three pairs of twins), regarding clinical manifestations for atopy during the first year of life. Their IgE levels in cord blood samples, at 3, 6, 9 and 12 months of age were measured and the influence of race, sex, breast-feeding, maternal smoking, family income, month of birth, family history and personal manifestations of atopic disease were evaluated. Total serum immunoglobulin E was quantified by microparticle enzyme immuno-assay (MEIA). The study group consisted of 60 (53%) male neonates, 67 (59%) Caucasians and 47 (41%) blacks. In the clinical follow-up, 32 (28.1%) infants developed obvious atopic disease: 29 infants presented recurrent wheezing, two had cow's milk allergy and one had atopic dermatitis. Probable atopic disease developed in 12 (10.5%) infants, whereas 70 (61.4%) infants showed no manifestations. Cord blood IgE levels in infants with obvious atopic disease was higher when compared to those without (p = 0.024), with 70.97% sensitivity and 46.2% specificity. IgE levels were also significantly different up to 12 months in these groups (p = 0.0001), when the sensitivity was 82.1% and the specificity 54.1%. At this age, the IgE levels were higher in infants with obvious atopy than nonatopic disease in relation to male sex (p = 0.015), black race (p = 0.009), breast-feeding for less than 6 months (p = 0.011) and when the family income was less than three times the minimum wage (about US $300) (p = 0.006). There was no association between IgE levels and family history of atopy. We concluded that immune response for atopy was in a large degree influenced by environmental factors and serum IgE at 12 months was a good marker for identifying infants with risk of atopic disease in early life.

Maximizing the xylitol production from sugar cane bagasse hydrolysate by controlling the aeration rate.

Batch fermentations of sugar cane bagasse hemicellulosic hydrolysate treated for removing the inhibitors of the fermentation were performed by Candida guilliermondii FTI20037 for xylitol production. The fermentative parameters agitation and aeration rate were studied aiming the maximization of xylitol production from this agroindustrial residue. The maximal xylitol volumetric productivity (0.87 g/L h) and yield (0.67 g/g) were attained at 400/min and 0.45 v.v.m. (K(L)a 27/h). According to the results, a suitable control of the oxygen input permitting the xylitol formation from sugar cane bagasse hydrolysate is required for the development of an efficient fermentation process for large-scale applications.