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Simonetta Picone, Roberto Aufieri, Piermichele PaolilloDivision of Neonatology and Neonatal Intensive Care, Department of Maternal and Child Health, Casilino General Hospital, Rome, ItalyAbstract: Apnea of prematurity is a developmental disorder that frequently affects preterm infants, especially those with lower gestational age. Even if apnea of prematurity is by definition a self-limiting condition, it can cause serious problems during the hospital stay and can potentially have long-term neurological and cognitive consequences depending on the severity and intensity of the episodes. The diagnosis of apnea of prematurity can be made only after excluding a number of diseases of the preterm infant in which apnea may be an epiphenomenon. Etiological diagnosis is essential for selection of appropriate treatment, which may be nonpharmacological or involve use of drugs.Keywords: apnea of prematurity, idiopathic and secondary apnea, caffeine

Abstract Background Early discharge of healthy late preterm and full term newborn infants has become common practice because of the current social and economic necessities. Severe jaundice, and even kernicterus, has developed in some term infants discharged early. This study was designed to elaborate a percentile-based hour specific total serum bilirubin (TSB) nomogram and to assess its ability to predict the absence of risk for subsequent non physiologic severe hyperbilirubinaemia before discharge. Methods A percentile-based hour-specific nomogram for TSB values was performed using TSB data of 1708 healthy full term neonates. The nomogram's predictive ability was then prospectively assessed in five different first level neonatal units, using a single TSB value determined before discharge. Results The 75 th percentile of hour specific TSB nomogram allows to predict newborn babies without significant hyperbilirubinemia only after the first 72 hours of life. In the first 48 hours of life the observation of false negative results did not permit a safe discharge from the hospital. Conclusion The hour-specific TSB nomogram is able to predict all neonates without risk of non physiologic hyperbilirubinemia only after 48 to 72 hours of life. The combination of TSB determination and risk factors for hyperbilirubinemia could facilitate a safe discharge from the hospital and a targeted intervention and follow-up.

Background: An effective strategy to reduce perinatal mortality requires an active surveillance system. This includes monitoring cases, organizing multidisciplinary local audits, conducting Confidential Enquiries, identifying avoidable factors, and facilitating changes in the healthcare system. In 2017, the Italian Obstetric Surveillance System launched the SPItOSS pilot Perinatal Surveillance System. The aim of this paper is to describe the results of the SPItOSS Confidential Enquiries on perinatal deaths focusing on the emergent critical aspects in obstetric and neonatal care, as well as on the healthcare facilities organization., Methods: SPItOSS, a population-based surveillance system, collected and analysed incident perinatal deaths from July 2017 to June 2019 in three Regions encompassing 32.3% of Italian births. Cases were defined according to WHO definition as fetuses born dead ≥ 28 weeks of gestation and live newborn died within 7 days from birth. The International Statistical Classification of Diseases and related Health Problem-Perinatal Mortality was adopted for coding causes of death and contributing maternal and placenta-related conditions. Confidential Enquiries, prioritized according to perinatal deaths preventability, were conducted by expert committees at Regional and National level., Results: A total of 830 incident perinatal deaths were notified, with 58.3% classified as antepartum, 4.3% as intrapartum, and 37.3% as neonatal deaths. According to the SPItOSS protocol, Confidential Enquiries evaluated only the most preventable deaths, including 19 intrapartum and 70 neonatal deaths. Of these, 43.8% were assessed as unavoidable with appropriate care; 29.2% as unavoidable with improvable care, and 15.7% as avoidable due to inappropriate care. Most intrapartum deaths were attributed to intrauterine hypoxia, while neonatal deaths recognized a multifactorial aetiology. Different aspects of inappropriate care were highlighted, such as failure to recognise maternal or fetal problems before labour, delayed or inappropriate neonatal resuscitation, and poor or suboptimal neonatal monitoring., Conclusions: The SPItOSS Confidential Enquires provided insights for improving maternity and perinatal services. By targeting key areas of obstetric and neonatal care, the surveillance can generate recommendations and actions to prevent avoidable perinatal deaths., Competing Interests: Declarations. Ethics approval and consent to participate: The Ethics Committee of the INIH evaluated the project and stated its unanimous ethical approval waiving the participants from the request for patient consent statement. The Protocol number is PRE-442/17, Rome 06/06/2017. The project was performed in accordance with the ethical standards as laid down in the Declaration of Helsinki and its later amendments or comparable ethical standards. Consent for publication: Not applicable. Competing interests: Carlo Dani, the editor of the journal, is one of the co-authors. No other competing interests have been declared., (© 2024. The Author(s).)

Breast milk is the natural source of nutrition for infants, but while it supports their health, it can also be a potential source of toxic inorganic particulate matter, and this applies to both breast milk and industrially produced milk. The aim of the present study was to evaluate the presence of nanoparticles in both breast milk and formula milk samples. We collected and analyzed, via a new electron scanning microscopic procedure, 19 samples of breast milk from Italian women and 19 formula milk samples produced by different companies. Organic-inorganic agglomerates were detected in 58% of formula and in 63% of breast milk samples, respectively. In addition, a significantly ( p < 0.05) greater size of nanoparticles was observed in formula milk samples. The results, showing the presence of inorganic nanosized particles in breast and artificial milk, may lead to future studies aimed at investigating possible nanosized contamination of milk and identifying early prevention strategies for women and animals involved in the food chain.

At the beginning of the pandemic, SARS-CoV-2 infection represented a great medical burden worldwide, as targeted and effective therapeutic options were lacking. This resulted in the revival of existing molecules and the increasing popularity of over-the-counter nutritional supplements. Among the latter, lactoferrin has been investigated as an adjuvant in COVID-19 therapy with conflicting results, mainly depending on different study designs. Considering that lactoferrin is one of the main components of human breast milk with anti-microbial and anti-inflammatory activity, it is conceivable that such bioactive molecule could be effective in supporting anti-SARS-CoV-2 infection therapy, especially in infants and pregnant women, two subpopulations that have been poorly evaluated in the existing clinical trials. This narrative review is intended to offer insight into the existing literature on lactoferrin's biological functions and protective effects against COVID-19, with a special focus on pregnant women and their infants.

Breast milk (BM) is a unique food due to its nutritional composition and anti-inflammatory characteristics. Evidence has emerged on the role of Presepsin (PSEP) as a reliable marker of early sepsis diagnosis. In the present study, we aimed to investigate the measurability of PSEP in BM according to different maturation stages (colostrum, C; transition, Tr; and mature milks, Mt) and corrected for delivery mode and gender. We conducted a multicenter prospective case-control study in women who had delivered 22 term (T) and 22 preterm (PT) infants. A total of 44 human milk samples were collected and stored at -80 °C. BM PSEP (pg/mL) levels were measured by using a rapid chemiluminescent enzyme immunoassay. PSEP was detected in all samples analyzed. Higher ( p < 0.05) BM PSEP concentrations were observed in the PT compared to the T infants. According to the grade of maturation, higher ( p < 0.05) levels of PSEP in C compared to Tr and Mt milks were observed in the whole study population. The BM subtypes' degrees of maturation were delivery mode and gender dependent. We found that PSEP at high concentrations supports its antimicrobial action both in PT and T infants. These results open the door to further studies investigating the role of PSEP.

A new Italian intersociety position statement on the prevention of ophthalmia neonatorum was published in 2023. In this document, attention was paid to the indications for the screening of gonococcal and chlamydial infections during pregnancy according to the international and national guidelines for the prevention of sexually transmitted infections (STIs). We conducted an observational retrospective study to assess whether the current guidelines for the prevention of STIs are being followed correctly. From February to August 2022, 2507 women nearing childbirth were enrolled. Among them, 42.4% received a swab for Chlamydia and only 0.5% for gonococcus. Concerning the geographical area of origin, most of the screened women came from Western Europe. None of the women who received gonococcal swabs and only 105 women out of 1062 screened for Chlamydia were under 25 years of age. Overall, only seven swabs were positive for Chlamydia , while none were positive for gonococcus. Concerning the age, geographical area of origin, and medical history of the women with a positive screening for Chlamydia , all were over 25 years old, six were from Western Europe, one was from South America, and none had other STIs. Although monocentric in nature, this study shows that the guidelines are not being followed correctly.

Enteroviruses (EVs) are ubiquitous viruses that circulate worldwide, causing sporadic or epidemic infections, typically during the summer and fall. They cause a broad spectrum of illnesses, ranging from an unspecified febrile clinical presentation to a severe illness. EVs are recognized to be the most frequent etiological agents of aseptic meningitis in children. However, as the infection is usually mild and self-limiting, it remains underestimated, and the epidemiology of EVs is poorly understood. To date, no vaccine or effective therapy for all types of enteroviruses is available, and EVs constitute a public health concern. Here, we investigated the molecular epidemiology of EV strains circulating in the Lazio region over a 10-year time span (2012-2023) by using a sequence-typing approach and phylogenetic analysis. The epidemiological trend of EV infection has undergone changes during the SARS-CoV-2 pandemic (2020-2021), which resulted in a modification in terms of the number of diagnosed cases and seasonality. From 2022, the circulation of EVs showed a behavior typical of the pre-pandemic period, although changes in predominantly circulating strains have been noted. Both epidemic and sporadic circulation events have been characterized in the Lazio region. Further analyses are needed to better characterize any strain with higher potential pathogenic power and to identify possible recombinant strains.

To date, the SARS-CoV-2 pandemic still represents a great clinical challenge worldwide, and effective anti-COVID-19 drugs are limited. For this reason, nutritional supplements have been investigated as adjuvant therapeutic approaches in disease management. Among such supplements, vitamin D has gained great interest, due to its immunomodulatory and anti-inflammatory actions both in adult and pediatric populations. Even if there is conflicting evidence about its prevention and/or mitigation effectiveness in SARS-CoV-2 infection, several studies demonstrated a strict correlation between hypovitaminosis D and disease severity in acute COVID-19 and MIS-C (multisystem inflammatory syndrome in children). This narrative review offers a resume of the state of the art about vitamin D's role in immunity and its clinical use in the context of the current pandemic, specially focusing on pediatric manifestations and MIS-C. It seems biologically reasonable that interventions aimed at normalizing circulating vitamin D levels could be beneficial. To help clinicians in establishing the correct prophylaxis and/or supportive therapy with vitamin D, well-designed and adequately statistically powered clinical trials involving both adult and pediatric populations are needed. Moreover, this review will also discuss the few other nutraceuticals evaluated in this context.

The selection of an appropriate dose of a given antibiotic for a neonate not only requires knowledge of the drug's basic pharmacokinetic (PK) and pharmacodynamic (PD) properties but also the profound effects that organ development might have on the volume of distribution and clearance, both of which may affect the PK/PD of a drug. Interest has grown in alternative antibiotic dosing strategies that are better aligned with the antibiotic's PK and PD properties. These strategies should be used in conjunction with minimum inhibitory concentration measurements and therapeutic drug monitoring to measure their potential success. They can also guide the clinician in tailoring the delivery of antibiotics to suit an individual patient's needs. Model-informed precision dosing, such as Bayesian forecasting dosing software (which incorporates PK/PD population models), may be utilized to optimize antibiotic exposure in neonatal populations. Consequently, optimizing the antibiotic dose and exposure in each newborn requires expertise in different fields. It drives the collaboration of physicians together with lab technicians and quantitative clinical pharmacologists.

Background: Preterm infants born between 33 and 35 weeks of gestational age (wGA) have been considered a "major underserved population" and ineligible to receive palivizumab (PLV), the only drug authorized to date for respiratory syncytial virus (RSV) prophylaxis, by current international guidelines. In Italy, such a vulnerable population is currently eligible for prophylaxis, and, in our region, specific risk factors are taken into consideration (SIN Lazio score) to target prophylaxis for those at highest risk. Whether the adoption of less or more restrictive eligibility criteria for PLV prophylaxis would translate into differences in bronchiolitis and hospitalization incidence is not known., Materials and Methods: A retrospective analysis was conducted in 296 moderate-to-late preterm infants (born between 33 and 35 +6 weeks) who were being considered for prophylaxis in two epidemic seasons: 2018-2019 and 2019-2020. The study participants were categorized according to both the SIN Lazio score and the Blanken risk scoring tool (BRST), which was found to reliably predict RSV-associated hospitalization in preterm infants on the basis of three risk factor variables., Results: Based on the SIN Lazio score, approximately 40% of infants (123/296) would meet the criteria to be eligible for PLV prophylaxis. In contrast, none of the analyzed infants would be considered eligible for RSV prophylaxis on the basis of the BRST. A total of 45 (15.2%) bronchiolitis diagnoses were recorded on average at 5 months of age in the overall population. Almost seven out of 10 (84/123) patients exhibiting ≥3 risk factors to be eligible for RSV prophylaxis according to SIN Lazio criteria would not be receiving PLV if they were categorized on the basis of the BRST. Bronchiolitis occurrence in patients with a SIN Lazio score ≥3 was approximately 2.2 times more likely than that in patients with a SIN Lazio score <3. PLV prophylaxis has been associated with a 91% lower risk of requiring a nasal cannula., Conclusion: Our work further supports the need for targeting late preterm infants for RSV prophylaxis and calls for an appraisal of the current eligibility criteria for PLV treatment. Therefore, adopting less restrictive criteria may ensure a comprehensive prophylaxis of the eligible subjects, thus sparing them from avoidable short- and long-term consequences of RSV infection., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Mondì, Paolillo, Bedetta, Lucangeli and Picone.)

Terrestrial locomotion requires coordinated bilateral activation of limb muscles, with left-right alternation in walking or running, and synchronous activation in hopping or skipping. The neural mechanisms involved in interlimb coordination at birth are well known in different mammalian species, but less so in humans. Here, 46 neonates (of either sex) performed bilateral and unilateral stepping with one leg blocked in different positions. By recording EMG activities of lower-limb muscles, we observed episodes of left-right alternating or synchronous coordination. In most cases, the frequency of EMG oscillations during sequences of consecutive steps was approximately similar between the two sides, but in some cases it was considerably different, with episodes of 2:1 interlimb coordination and episodes of activity deletions on the blocked side. Hip position of the blocked limb significantly affected ipsilateral, but not contralateral, muscle activities. Thus, hip extension backward engaged hip flexor muscle, and hip flexion engaged hip extensors. Moreover, the sudden release of the blocked limb in the posterior position elicited the immediate initiation of the swing phase of the limb, with hip flexion and a burst of an ankle flexor muscle. Extensor muscles showed load responses at midstance. The variable interlimb coordination and its incomplete sensory modulation suggest that the neonatal locomotor networks do not operate in the same manner as in mature locomotion, also because of the limited cortical control at birth. These neonatal mechanisms share many properties with spinal mammalian preparations (i.e., independent pattern generators for each limb, and for flexor and extensor muscles, load, and hip position feedback). SIGNIFICANCE STATEMENT Bilateral coupling and reciprocal activation of flexor and extensor burst generators represent the fundamental mechanisms used by mammalian limbed locomotion. Considerable progress has been made in deciphering the early development of the spinal networks and left-right coordination in different mammals, but less is known about human newborns. We compared bilateral and unilateral stepping in human neonates, where cortical control is still underdeveloped. We found neonatal mechanisms that share many properties with spinal mammalian preparations (i.e., independent pattern generators for each limb, the independent generators for flexor and extensor muscles, load, and hip-position feedback. The variable interlimb coordination and its incomplete sensory modulation suggest that the human neonatal locomotor networks do not operate in the same manner as in mature locomotion., (Copyright © 2022 the authors.)

Listeriosis is currently the fifth most common foodborne disease in Europe. Most cases are sporadic; however, outbreaks have also been reported. Compared to other foodborne infections, listeriosis has a modest incidence but can cause life-threatening complications, especially in elderly or immunocompromised people and pregnant women. In the latter case, the pathology can be the cause of premature birth or spontaneous abortion, especially if the fetus is affected during the first months of gestation. The causative agent of listeriosis, Listeria monocytogenes , is characterized by the innate ability to survive in the environment and in food, even in adverse conditions and for long periods. Ready-to-eat food represents the category most at risk for contracting listeriosis. This study presents the result of an investigation carried out on a case of maternal-fetal transmission of listeriosis which occurred in 2020 in central Italy and which was linked, with a retrospective approach, to other cases residing in the same city of the pregnant woman. Thanks to the use of next-generation sequencing methodologies, it was possible to identify an outbreak of infection, linked to the consumption of ready-to-eat sliced products sold in a supermarket in the investigated city.

Background: S100B is an established biomarker of brain development and damage. Lutein (LT) is a naturally occurring xanthophyll carotenoid mainly concentrated in the central nervous system (CNS), but its neurotrophic role is still debated. We investigated whether LT cord blood concentrations correlate with S100B in a cohort of preterm and term healthy newborns., Methods: We conducted a prospective study on the distribution of LT and S100B in arterial cord blood of healthy preterm (n = 50) and term (n = 50) newborns., Results: S100B and LT showed a pattern of concentration characterized by higher levels (P < 0.01, for all) at 33-36 weeks gestation (GA) followed by a progressive decrease (P < 0.01, for all) from 37 onwards with a dip at term. Both S100B and LT were gender-dependent with significantly (P < 0.01, for all) higher levels in females in preterm and term groups. S100B (R = 0.68; P < 0.001) and LT (R = 0.40; P = 0.005) correlated with GA at sampling. A positive significant correlation (R = 0.87; P < 0.001) between S100B and LT was found., Conclusions: The present data showing a correlation between S100B and LT supports the notion of a LT trophic role in the CNS. Further investigations in high-risk infants are needed to elucidate LT involvement in the pathophysiological cascade of events leading to CNS development and damage., (© 2022. The Author(s).)

Lutein is a dietary carotenoid preferentially accumulated in the eye and the brain in early life and throughout the life span. Lutein accumulation in areas of high metabolism and oxidative stress such as the eye and the brain suggest a unique role of this ingredient during the development and maturation of these organs of common embryological origin. Lutein is naturally provided to the developing baby via the cord blood, breast milk and then infant diet. The presence of this carotenoid depends on fruit and vegetable intakes and its bioavailability is higher in breastmilk. This paper aims to review the anatomical development of the eye and the brain, explore the presence and selective deposition of lutein in these organs during pregnancy and infancy and, based on its functional characteristics, present the latest available research on the beneficial role of lutein in the pediatric population. The potential effects of lutein in ameliorating conditions associated with increase oxidative stress such as in prematurity will be also addressed. Since consumption of lutein rich foods falls short of government guidelines and in most region of the world infant formulas lack this bioactive, dietary recommendations for pregnant and breastfeeding women and their child can help to bridge the gap.

Mature locomotion involves modular spinal drives generating a set of fundamental patterns of motoneuron activation, each timed at a specific phase of locomotor cycles and associated with a stable muscle synergy. How locomotor modules develop and to what extent they depend on prior experience or intrinsic programs remains unclear. To address these issues, we herein leverage the presence at birth of two types of locomotor-like movements, spontaneous kicking and weight-bearing stepping. The former is expressed thousands of times in utero and postnatally, whereas the latter is elicited de novo by placing the newborn on the ground for the first time. We found that the neuromuscular modules of stepping and kicking differ substantially. Neonates kicked with an adult-like number of temporal activation patterns, which lacked a stable association with systematic muscle synergies across movements. However, on the ground neonates stepped with fewer temporal patterns but all structured in stable synergies. Since kicking and ground-stepping coexist at birth, switching between the two behaviors may depend on a dynamic reconfiguration of the underlying neural circuits as a function of sensory feedback from surface contact. We tracked the development of ground-stepping in 4- to 48-mo-old infants and found that, after the age of 6 mo, the number of temporal patterns increased progressively, reaching adult-like conformation only after independent walking was established. We surmise that mature locomotor modules may derive by combining the multiple patterns of repeated kicking, on the one hand, with synergies resulting from fractionation of those revealed by sporadic weight-bearing stepping, on the other hand., Competing Interests: The authors declare no competing interest.

Background: The only pharmacologic prophylaxis against respiratory syncytial virus (RSV) infection in preterm infants is the humanized monoclonal antibody palivizumab. After the 2014 modification of the American Academy of Pediatrics (AAP) recommendations, the Italian Medicines Agency (AIFA) limited the financial coverage for palivizumab prescriptions to otherwise healthy preterm infants with < 29 weeks of gestational age (wGA) aged < 12 months at the beginning of the 2016-2017 RSV season. However, due to the effect on disease severity and hospitalizations following this limitation, shown by several Italian clinical studies, in November 2017 AIFA reinstated the financial coverage for these infants. In this systematic review, we critically summarize the data that show the importance of palivizumab prophylaxis., Methods: Data from six Italian pediatric institutes and the Italian Network of Pediatric Intensive Care Units (TIPNet) were retrieved from the literature and considered. The epidemiologic information for infants 29-36 wGA, aged < 12 months and admitted for viral-induced acute lower respiratory tract infection were retrospectively reviewed. RSV-associated hospitalizations were compared between the season with running limitation, i.e. 2016-2017, versus 2 seasons before (2014-2015 and 2015-2016) and one season after (2017-2018) the AIFA limitation., Results: During the 2016-2017 RSV epidemic season, when the AIFA limited the financial coverage of palivizumab prophylaxis based on the 2014 AAP recommendation, the study reports on a higher incidences of RSV bronchiolitis and greater respiratory function impairment. During this season, we also found an increase in hospitalizations and admissions to the Pediatric Intensive Care Units and longer hospital stays, incurring higher healthcare costs. During the 2016-2017 epidemic season, an overall increase in the number of RSV bronchiolitis cases was also observed in infants born full term, suggesting that the decreased prophylaxis in preterm infants may have caused a wider infection diffusion in groups of infants not considered to be at risk., Conclusions: The Italian results support the use of palivizumab prophylaxis for otherwise healthy preterm (29-36 wGA) infants aged < 6 months at the beginning of the RSV season.

Objectives: To investigate the modulation of genes whose expression level is indicative of stress and toxicity following exposure to three anaesthesia techniques, general anaesthesia (GA), regional anaesthesia (RA), or integrated anaesthesia (IA)., Methods: Patients scheduled for hip arthroplasty receiving GA, RA and IA were enrolled at Rizzoli Orthopaedic Institute of Bologna, Italy and the expression of genes involved in toxicology were evaluated in peripheral blood mononuclear cells (PBMCs) collected before (T0), immediately after surgery (T1), and on the third day (T2) after surgery in association with biochemical parameters., Results: All three anaesthesia methods proved safe and reliable in terms of pain relief and patient recovery. Gene ontology analysis revealed that GA and mainly IA were associated with deregulation of DNA repair system and stress-responsive genes, which was observed even after 3-days from anaesthesia. Conversely, RA was not associated with substantial changes in gene expression., Conclusions: Based on the gene expression analysis, RA technique showed the smallest toxicological effect in hip arthroplasty., Trial Registration: ClinicalTrials.gov number NCT03585647., Competing Interests: The authors have declared that no competing interests exist.

Background: Adrenomedullin (AM) is a potent angiogenic, antioxidant and anti-inflammatory peptide protecting the developing lung from injury due to bronchopulmonary dysplasia (BPD) of the preterm infant. At this stage, no data on the potential effects of chorioamnionitis (CA) occurrence and glucocorticoids (GC) administration on AM in developing lungs are still lacking., Objective: to investigate, in a sheep-based model, the positive/side-effects of combined exposure to CA and GC on AM concentrations measured in bronchoalveolar lavage fluid (BALF)., Methods: Time-mated ewes were randomly admitted to one of six treatment groups receiving injection: saline (controls); lipopolysaccharide (L) in intra-amniotic fluid treated alone at 7 or 14 d before delivery or associated with betamethasone (B) intramuscularly; B treated alone (7d) or associated with L (14d). Lambs were surgically delivered at 120 days gestation and euthanized. BALF was used for AM measurement in the studied groups., Results: AM BALF levels significantly ( p  < 0.05, for all) changed both to B and L exposure in a time-dependent manner. The latter was characterized by AM levels at short term superimposable to controls, whilst significantly ( p  > 0.05) decreased at long-term. The former showed increased AM at short and decreased at long-term ( p  < 0.05, for all), respectively., Conclusions: the present results showing AM BALF changes in a sheep-based model support the AM role in the hemodynamic patterns due to CA and BPD occurrence and open the way to further studies investigating the role of vasoactive agents as trustable markers of lung development/damage.

Congenital leukemia is a very rare severe condition and leukemia cutis may represent the presenting sign of this malignancy, sometimes preceding hematological findings of weeks. Typical clinical features include multiple red to purple papules, macules and nodules due to direct infiltration of the skin by malignant cells. We illustrate these cutaneous findings in a patient with congenital leukemia and tetralogy of Fallot.

Contaminant biodegradation in unsaturated soils may reduce the risks of vapor intrusion. However, the reported rates show large variability and are often derived from slurry experiments that are not representative of unsaturated conditions. Here, different laboratory setups are used to derive the biodegradation capacity of an unsaturated soil layer through which gaseous toluene migrates from the water table upwards. Experiments in static unsaturated soil microcosms at 6-30 % water-filled porosity (WFP) and unsaturated soil columns at 9, 14, and 27 % WFP were compared with liquid batches containing the same culture of Alicycliphilus denitrificans. The biodegradation rates for the liquid batches were orders of magnitude lower than for the other setups. Hence, liquid batches do not necessarily reflect optimal conditions for bacteria; either oxygen or toluene mass transfer at the cell scale or the absence of soil-water-air interfaces seemed to be limiting bacterial activity. For the column setup, the rates were limited by mass supply. The microcosm results could be described by apparent first-order biodegradation constants that increased with WFP or through a numerical model that included biodegradation as a first-order process taking place in the liquid phase only. The model liquid phase first-order rates varied between 6.25 and 20 h(-1) and were not related to the water content. Substrate availability was the primary factor limiting bioactivity, with evidence for physiological stress at the lowest water-filled porosity. The presented approach is useful to derive liquid phase biodegradation rates from experimental data and to include biodegradation in vapor intrusion models.

Many reactions in cells proceed via the sequestration of two DNA molecules in a synaptic complex. SfiI is a member of a growing family of restriction enzymes that can bind and cleave two DNA sites simultaneously. We present here the structures of tetrameric SfiI in complex with cognate DNA. The structures reveal two different binding states of SfiI: one with both DNA-binding sites fully occupied and the other with fully and partially occupied sites. These two states provide details on how SfiI recognizes and cleaves its target DNA sites, and gives insight into sequential binding events. The SfiI recognition sequence (GGCCNNNN[downward arrow]NGGCC) is a subset of the recognition sequence of BglI (GCCNNNN[downward arrow]NGGC), and both enzymes cleave their target DNAs to leave 3-base 3' overhangs. We show that even though SfiI is a tetramer and BglI is a dimer, and there is little sequence similarity between the two enzymes, their modes of DNA recognition are unusually similar.

Acute appendicitis is the most common diagnosis made (in the Western world) in patients with an "acute abdomen." Although the mortality rate has been vastly reduced, the diagnostic inaccuracy rate of 15% to 20% has remained unchanged in the past 100 years. In this article, the authors report the ultrasonographic findings in 80 patients examined using a small linear-array transducer, which enables direct visualization of the inflamed appendix. During 22 months, 80 patients (28 males and 52 females; age range, 3 to 81 years; mean, 32.3 years) with equivocal clinical signs and symptoms of acute appendicitis were examined sonographically. Of the 29 patients whose appendicitis was verified at surgery, ultrasonography was positive in 26, with an overall sensitivity of 90%. Of the 51 patients who did not have appendicitis, ultrasonography was negative in all, with a specificity of 100%. The authors concur with reports in the literature that ultrasonography is helpful in diagnosing appendicitis.