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One of the techniques utilized to enhance the heat transfer rate within air ducts is creating turbulence inducing designs. In this work, turbulent air flow through a rectangular cross-sectional duct with one corrugated surface was experimentally and numerically investigated. Hydraulic and thermal behaviors of the system were evaluated at different Reynolds numbers. A test rig was constructed to experimentally investigate the performance. Also, a two-dimensional computational fluid dynamics simulation was performed using k-ε model to simulate fluid flow within the duct. The model was validated against previous results as well as the experimental results from this research. The computational and experimental findings were in reasonable agreement with a maximum error of less than 10%. The results showed that the existence of the corrugated surface considerably enhanced the heat transfer rate in all the studied cases, while slightly increasing the pressure drop. Consequently, a parametric study was performed to investigate the effect of different design parameters on the performance. The best performance was observed at a rib height to width ratio of 0.2, and groove length to width ratio of three, with a thermal enhancement factor of about 1.5. an empirical relation between Nusselt number and Reynolds number was established using the obtained results with a relative error value less than 8%. The study proved the value of using a corrugated surface as a means to increase heat transfer rate within rectangular air ducts.

Although heterotopic ossification (HO) after total hip arthroplasty has been very well described as a cause of disability, much less was written on clinical dysfunction of HO after total knee arthroplasty (TKA). To the extent of our knowledge, there has been no published case of complete bony ankylosis, secondary to severe generalized HO, after a TKA. We present the case of a 67-year-old female treated successfully, with surgical excision of ossification and TKA revision surgery, using a rotating hinge system.

OBJETIVO: O arqueamento das pernas geralmente é atribuído ao raquitismo causado pela carência de vitamina D; portanto, várias crianças afetadas acabam sendo classificadas erroneamente e tratadas inadequadamente. Este caso ilustra como uma avaliação clínica e radiológica cuidadosa pode levar à elucidação de sua causa. DESCRIÇÃO: Relatamos um caso esporádico de um menino de 2 anos de idade que apresentou achados radiológicos compatíveis com síndrome de Weismann-Netter-Stuhl. Além disso, observamos o complexo de malformação craniovertebral. O paciente possuía inteligência normal. Até onde sabemos, a combinação de síndrome de Weismann-Netter-Stuhl e occipitalização do atlas hipoplásico e posterior fusão das vértebras C2 e C3 nunca foi relatada antes. Descrevemos o diagnóstico da síndrome de Weismann-Netter-Stuhl. As características clássicas da síndrome de Weismann-Netter-Stuhl são baixa estatura, retardamento mental (em alguns indivíduos), calcificação da dura-máter e arqueamento anterior da tíbia. Todavia, acreditamos que um exame clínico e radiológico cuidadoso possa revelar dados mais contundentes que poderiam influenciar positivamente o processo de tratamento. COMENTÁRIOS: Presumimos que as limitações congênitas dos movimentos do pescoço em nosso paciente surgiram por causa da fusão acentuada do osso occipital ao atlas hipoplásico e da fusão simultânea da segunda e terceira vértebras. Portanto, se desconsiderarmos esse tipo de malformação, a estrutura atlanto-axial poderá ser comprometida, o que poderá causar complicações neurológicas sérias e até mesmo fatais. A tomografia tem um papel crucial na detecção dessas anormalidades.OBJECTIVE: Bowing of the legs is usually thrown into the basket of vitamin D deficiency rickets; therefore, a significant number of affected children can be misdiagnosed and improperly managed. This case illustrates how the careful clinical and radiological assessment of such a case can lead to the adequate understanding of its etiology. DESCRIPTION: We report a sporadic case of a 2-year-old male child who presented with radiological features that were compatible with Weismann-Netter-Stuhl syndrome. In addition, we observed craniovertebral malformation complex. He was of normal intelligence. To our knowledge, the combination of Weismann-Netter-Stuhl syndrome and presence of a hypoplastic occipitalized atlas and further C2-C3 fusion has not been reported before. The diagnosis of Weismann-Netter-Stuhl is discussed. Classically, Weismann-Netter-Stuhl syndrome is characterized by short stature, mental retardation (in some individuals), dural calcification, and anterior bowing of the tibiae. However, we believe that careful clinical and radiological examinations can reveal more striking data which might positively reflect on the whole process of management. COMMENTS: We postulate that the congenital limitations in neck movements in our patient developed because of the marked fusion of the hypoplastic and occipitalized atlas and simultaneous C2-C3 fusion. Therefore, if this form of malformation is disregarded, there may be involvement of the atlantoaxial structure, and this can possibly lead to serious neurological and even life-threatening complications. The use of CT scanning for the detection of such abnormalities can be remarkably important.

Endoscopic Ultrasound (EUS) stands as a remarkable innovation in the realm of gastroenterology and its allied disciplines. EUS has evolved to such an extent that it now assumes a pivotal role in both diagnosis and therapeutics. In addition, it has developed as a tool which is also capable of addressing complications arising from endoscopic and surgical procedures. This minimally invasive technique combines endoscopy with high-frequency ultrasound, facilitating, high-resolution images of the gastrointestinal tract and adjacent structures. Complications within the gastrointestinal tract, whether stemming from endoscopic or surgical procedures, frequently arise due to disruption in the integrity of the gastrointestinal tract wall. While these complications are usually promptly detected, there are instances where their onset is delayed. EUS plays a dual role in the management of these complications. Firstly, in its ability to assess and increasingly to definitively manage complications through drainage procedures. It is increasingly employed to manage post-surgical collections, abscesses biliary strictures and bleeding. Its high-resolution imaging capability allows precise real-time visualisation of these complications., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Nadeem Tehami reports was provided by University Hospital Southampton NHS Foundation Trust. Nadeem Tehami reports a relationship with University Hospital Southampton NHS Foundation Trust that includes: employment. Nadeem Tehami has patent NA pending to NA. None If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

One aim of roadside green infrastructure (GI) is to mitigate exposure to local, traffic-generated pollutants. Here, we determine the efficacy of roadside GI in improving local air quality through the deposition and/or dispersion of airborne particulate matter (PM). PM was collected on both pumped air filters and on the leaves of a recently installed 'tredge' (trees managed as a head-high hedge) at an open road environment next to a primary school in Manchester, U.K. The magnetic properties of PM deposited on leaves and filters (size fractions PM 10 and PM 2.5 ) were deduced from hysteresis loops, first-order reversal curves (FORCs), and low-temperature remanence measurements. These were complemented with electron microscopy to identify changes in magnetic PM concentration downwind of the tredge/GI. We show that the tredge is permeable to airflow using a simple CO 2 tracer experiment; hence, it allows interception and subsequent deposition of PM on its leaves. Magnetic loadings per m 3 of air from filters (PM 10 saturation magnetisation, M s , at 5 K) were reduced by 40 % behind the tredge and a further 63 % in the playground; a total reduction of 78 % compared to roadside air. For the PM 2.5 fraction, the reduction in magnetic loading behind the tredge was remarkable (82 %), reflecting efficient diffusional capture of sub-5 nm Fe-oxide particles by the tredge. Some direct mixing of roadside and playground air occurs at the back of the playground, caused by air flow over, and/or through gaps in, the slowly-permeable tredge. The magnetic loading on tredge leaves increased over successive days, capturing ~23 % of local, traffic-derived PM 10 . Using a heuristic two-dimensional turbulent mixing model, we assess the limited dispersion of PM < 22.5 μm induced by eddies in the tredge wake. This study demonstrates that PM deposition on leaves reduces exposure significantly in this school playground setting; hence, providing a cost-effective mitigation strategy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: We aimed to identify distinct trajectories of tobacco, cannabis, and their co-use among African Americans, and to investigate whether these patterns were associated with polygenic risk scores (PRS) for tobacco and cannabis use., Method: Participants (N=428 participants; 50.9% male) were initially recruited for an elementary school-based prevention in a Mid-Atlantic city when they were in first grade. From ages 14-26, participants reported on their frequency of tobacco and cannabis use in the past year during annual assessments. DNA was collected from participants at age 21. PRS for smoking heaviness (i.e., cigarettes per day) and lifetime cannabis use were created based on genome-wide association study results derived from Liu et al. (2019) and Pasman et al. (2018), respectively., Results: We identified five distinct trajectories of tobacco and cannabis co-use, including (1) Low Tobacco and Cannabis Use, (2) Adolescent Limited Tobacco and Cannabis Use, (3) Experimental Cannabis, Young Adult Increasing Tobacco, (4) Experimental Tobacco, Young Adult Increasing Cannabis, and (5) High, Chronic Tobacco and Cannabis Use. Compared to the Low Tobacco and Cannabis Use subgroup, individuals in the High, Chronic Tobacco and Cannabis Use subgroup had greater PRS for smoking heaviness, and individuals in the Experimental Cannabis, Young Adult Increasing Tobacco subgroup had higher PRS for lifetime cannabis use., Conclusions: Polygenic risk for lifetime cannabis use and smoking heaviness is associated with the developmental progression of tobacco and cannabis co-use among African Americans, furthering knowledge on the etiology of co-use in this population., Competing Interests: Declaration of Competing Interest The authors report no conflicts of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Introduction: Paediatric varicocele embolization has many benefits over surgical ligation, but lacks published long-term data. We investigated technical and clinical outcomes in this under reported patient group., Objective: To evaluate technical success, complications and recurrence rates following varicocele embolization in paediatric patients., Materials and Methods: A single-centre retrospective review of procedural data and electronic notes of consecutive patients referred for varicocele embolization over a 10-year period was performed (February 2010-March 2020). The primary outcomes were technical success and clinical efficacy (lack of symptom recurrence). Secondary outcomes included complications, testicular vein size reduction and procedural parameters including radiation exposure. Chi-square analysis was used to identify predictors of clinical success. Follow-up involved outpatient clinical assessment and telephone interview., Results: 40 patients (median age 15) were referred for left-sided symptomatic varicocele. Technical embolization success was achieved in 36/40 patients (90%), with 4 procedures abandoned (inaccessible vein). Embolization technique was platinum-based coils ± sclerosant. There were no immediate or long-term procedural complications. 32/36 patients completed short term follow-up at a median interval of 2.8 months. 30/32 (93.78%) experienced early clinical success. We found a significant reduction in peritesticular vein size following embolization (pre-3.70 vs post-2.56 mm, p = 0.00017) and a significant relationship between varicocele grade and early clinical success (χ2 = 4.2, p = 0.04), but not pre-treatment peritesticular vein size (χ2 = 0.02, p = 0.88). 33/36 patients completed long-term follow-up (median 4.2 years, range 0.36-9.9 years) producing a late clinical success rate of 93.9% (31/33). No post procedural complications including hydroceles were identified., Discussion: This study demonstrates technical success, matching rates described in adult patients which is reassuring and in support of embolization in the younger patient cohort. More importantly, the overall clinical success rate is comparable with previous embolization studies. Reassuringly, all symptom recurrences occurred early in follow-up, and there is a cogent argument for a single follow-up appointment at this juncture. Our long-term average follow-up duration, primarily gained via telephone interview, exceeds other studies. Although our study has the longest follow-up for varicocele embolization in children, it is limited by a few patients being lost to early and long-term follow-up. This is a recognised issue faced by studies attempting to follow-up benign conditions with a high clinical success rate., Conclusion: Paediatric varicocele embolization is a successful alternative to surgical ligation, with no complications and good clinical outcomes over a long-term follow-up., Competing Interests: Conflict of interest None., (Copyright © 2021 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.)

Background: Although much of the attention surrounding the opioid epidemic has focused on rural and suburban Whites and prescription opioids, heroin overdoses among urban Blacks are on the rise. While some argue that legalization of cannabis will combat the epidemic, there are concerns it ignores the shift in the epidemic and could increase vulnerability to opioid misuse. The goal of this study is to examine the association between cannabis use from adolescence to young adulthood with opioid misuse in a primarily urban Black cohort., Methods: Data are from a study of 580 youth (87 % Black and 71 % low SES) residing in Baltimore City followed from ages 6-26. Cannabis trajectories were identified between ages 14-26 using group-based trajectory modeling. Logistic regressions were conducted to examine the impact of trajectories on opioid misuse in young adulthood adjusting for individual, neighborhood and peer factors. Opioid misuse was defined as using heroin or narcotics or painkillers without a prescription between ages 19-26., Results: Four cannabis trajectories were identified: Low/Non-Users (59.7 %), Adolescent Onset Limited (19.5 %), Young Adult Onset (10.8 %), and Adolescent Onset Chronic (10.0 %). Adolescent Onset Chronic cannabis users had the highest rate of opioid misuse (44.8 %) followed by Adolescent Onset Limited (18.8 %), Young Adult Onset (14.8 %) and Low/Non-Users (8.3 %). Prevalences were significantly higher for Adolescent Onset groups relative to Low/Non-Users even after adjustment for individual, neighborhood and peer factors., Conclusions: Adolescent onset cannabis use is associated with opioid misuse in young adulthood among urban Blacks even after adjustment for socioecological factors associated with opioid misuse., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Autosomal dominant mutations in transcription factor 4 (TCF4) are associated with a rare syndromic form of Autism Spectrum Disorder (ASD) called Pitt-Hopkins Syndrome (PTHS). Here, we report the generation of a collection of induced pluripotent stem cells (iPSCs) from 5 patients diagnosed with PTHS and 5 familial controls. These patient-derived iPSCs contain a variety of mutations within the TCF4 gene, possess a normal karyotype and express all the appropriate pluripotent stem cell markers. These novel patient lines will be a useful resource for the research community to study PTHS and the function of TCF4., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Author(s). Published by Elsevier B.V. All rights reserved.)

Objectives: Face masks are an important component of personal protection equipment employed in preventing the spread of diseases such as COVID-19. As the supply of mass-produced masks has decreased, the use of homemade masks has become more prevalent. It is important to quantify the effectiveness of different types of materials to provide useful information, which should be considered for homemade masks., Methods: Filtration effects of different types of common materials were studied by measuring the aerosol droplet concentrations in the upstream and downstream regions. Flow-field characteristics of surrounding regions of tested materials were investigated using a laser-diagnostics technique, i.e., particle image velocimetry. The pressure difference across the tested materials was measured., Results: Measured aerosol concentrations indicated a breakup of large-size particles into smaller particles. Tested materials had higher filtration efficiency for large particles. Single-layer materials were less efficient, but they had a low pressure-drop. Multilayer materials could produce greater filtering efficiency with an increased pressure drop, which is an indicator of comfort level and breathability. The obtained flow-fields indicated a flow disruption downstream of the tested materials as the velocity magnitude noticeably decreased., Conclusions: The obtained results provide an insight into flow-field characteristics and filtration efficiency of different types of household materials commonly used for homemade masks. This study allows comparison with mass-produced masks under consistent test conditions while employing several well-established techniques., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Exposure to particulate air pollution is a major environmental risk factor for cardiovascular mortality and morbidity, on a global scale. Both acute and chronic cardiovascular impacts have so far been attributed to particulate-mediated oxidative stress in the lung and/or via 'secondary' pathways, including endothelial dysfunction, and inflammation. However, increasing evidence indicates the translocation of inhaled nanoparticles to major organs via the circulation. It is essential to identify the composition and intracellular targets of such particles, since these are likely to determine their toxicity and consequent health impacts. Of potential major concern is the abundant presence of iron-rich air pollution nanoparticles, emitted from a range of industry and traffic-related sources. Bioreactive iron can catalyse formation of damaging reactive oxygen species, leading to oxidative stress and cell damage or death. Here, we identify for the first time, in situ, that exogenous nanoparticles (~15-40 nm diameter) within myocardial mitochondria of young, highly-exposed subjects are dominantly iron-rich, and co-associated with other reactive metals including aluminium and titanium. These rounded, electrodense nanoparticles (up to ~ 10 x more abundant than in lower-pollution controls) are located within abnormal myocardial mitochondria (e.g. deformed cristae; ruptured membranes). Measurements of an oxidative stress marker, PrP C and an endoplasmic reticulum stress marker, GRP78, identify significant ventricular up-regulation in the highly-exposed vs lower-pollution controls. In shape/size/composition, the within-mitochondrial particles are indistinguishable from the iron-rich, combustion- and friction-derived nanoparticles prolific in roadside/urban environments, emitted from traffic/industrial sources. Incursion of myocardial mitochondria by inhaled iron-rich air pollution nanoparticles thus appears associated with mitochondrial dysfunction, and excess formation of reactive oxygen species through the iron-catalyzed Fenton reaction. Ventricular oxidative stress, as indicated by PrP C and GRP78 up-regulation, is evident even in children/young adults with minimal risk factors and no co-morbidities. These new findings indicate that myocardial iron overload resulting from inhalation of airborne, metal-rich nanoparticles is a plausible and modifiable environmental risk factor for cardiac oxidative stress and cardiovascular disease, on an international scale., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Objectives: Comparison of outcomes for cancer patients discussed and not discussed at a multidisciplinary meeting (MDM)., Study Design: Retrospective analysis of the association of MDM discussion with survival., Methods: All newly diagnosed cancer patients from 2009 to 2012, presenting to a large regional cancer service in South West Victoria, Australia (620 colorectal, 657 breast, 593 lung and 511 haematological) were recorded and followed up to 5 years after diagnosis. Treatment patterns and survival of patients whose treatment was discussed at an MDM compared to those who were not, were explored., Results: The proportion of patients presented to an MDM within 60 days after diagnosis was 56% (n = 366) for breast cancer, 59% (n = 363) for colorectal cancer, 27% (n = 137) for haematological malignancies and 60% (n = 355) for lung cancer. Seventy-three percent (n = 886) of patients discussed at an MDM had their tumour stage recorded in their medical records while only 52% (n = 604) of patients not discussed had their tumour stage recorded (P < 0.01). We found for haematological and lung cancer patients that those presented to an MDM prior to treatment had a significant reduction in mortality (lung cancer hazard ratio [HR] 0.62, 95% confidence interval [CI] 0.50-0.76, P < 0.01) (haematological cancer HR 0.58, 95% CI 0.35-0.96, P = 0.03) compared to patients whose cases were not discussed at an MDM after adjusting for the potential cofounders of age, stage, comorbidities and treatment. This was not the case for colorectal and breast cancer patients where there was no significant difference., Conclusion: MDM discussion has been recommended as best practice in the management of cancer patients, however, from a public health perspective this creates potential issues around access and resources. It is likely that MDM presentation patterns and outcomes across tumour streams are linked in complex ways. We believe that our data would demonstrate that these patterns differ across tumour streams and that more detailed work is required to better allocate relatively scarce and potentially costly MDM resources to tumour streams and patient groups that may get the most benefit., (Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.)

Obsessive-compulsive disorder (OCD) and Autism spectrum disorder (ASD) are both highly heritable neurodevelopmental disorders that conceivably share genetic risk factors. However, the underlying genetic determinants remain largely unknown. In this work, the authors describe a combined genome-wide association study (GWAS) of ASD and OCD. The OCD dataset includes 2998 individuals in nuclear families. The ASD dataset includes 6898 individuals in case-parents trios. GWAS summary statistics were examined for potential enrichment of functional variants associated with gene expression levels in brain regions. The top ranked SNP is rs4785741 (chromosome 16) with P value=6.9×10 -7 in our re-analysis. Polygenic risk score analyses were conducted to investigate the genetic relationship within and across the two disorders. These analyses identified a significant polygenic component of ASD, predicting 0.11% of the phenotypic variance in an independent OCD data set. In addition, we examined the genomic architecture of ASD and OCD by estimating heritability on different chromosomes and different allele frequencies, analyzing genome-wide common variant data by using the Genome-wide Complex Trait Analysis (GCTA) program. The estimated global heritability of OCD is 0.427 (se=0.093) and 0.174 (se=0.053) for ASD in these imputed data., (Published by Elsevier B.V.)

Obsessive-compulsive disorder (OCD) is a polygenic neuropsychiatric disorder characterized by repetitive thoughts and behaviors that cause distress. The pathogenic repeat expansion [GGGGCC] n found at the C9orf72 locus is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), and has also been documented in patients with psychosis and schizophrenia. Furthermore, obsessions and compulsions have been identified in patients diagnosed with ALS and/or FTD and carrying the pathogenic repeat expansion. Here, we performed genetic screening for the C9orf72 repeat expansion on 573 patients diagnosed with OCD. None of the patients were found to carry the expansion. The results show that patients with OCD do not commonly carry the pathogenic repeat expansion and therefore should not be routinely screened. OCD and psychotic patients who do test positive for the C9orf72, however, should be closely observed for the later development of FTD and ALS., (Published by Elsevier B.V.)

Objectives: The information needs of cancer patients are highly variable. Literature suggests an improved ability to modulate personalised stress, increased patient involvement with decision making, greater satisfaction with treatment choices and reduced anxiety levels in cancer patients who have access to information. The aim of this project was to evaluate the effects of a mobile information application on anxiety levels of patients undergoing surgery for breast cancer., Materials and Methods: An application was developed for use with Apple iPad containing information on basic breast cancer biology, different treatments used and surgical techniques. Content and face validity studies were performed. A randomized control trial was designed, with a 1:2 allocation. Data collected include basic demographics and type of surgery. Questionnaires used included: the HADS, Mini-MAC, information technology familiarity and information satisfaction., Results: A total of 39 women participated. 13 women had access to an iPad containing additional information and 26 women acted as controls. The mean age was 54 and technology familiarity was similar among both groups. Anxiety and depression scores at seven days were significantly lower in control patients without access to the additional information provided by the mobile application (p = 0.022 and 0.029 respectively)., Conclusion: Anxiety and depression in breast cancer patients is both multifactorial and significant, with anxiety levels directly correlating with reduced quality of life. Intuitively, information should improve anxiety levels, however, we have demonstrated that surgical patients with less information reported significantly lower anxiety. We advise the thorough testing and auditing of information initiatives before deployment., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Compared to studies in adults, there have been few studies of hoarding in children and adolescents with obsessive-compulsive disorder (OCD). In the current study, we evaluated OCD clinical features, Axis I disorders, and social reciprocity scores in 641 children and adolescents with OCD, of whom 163 (25%) had hoarding compulsions and 478 did not. We found that, as a group, youth with hoarding had an earlier age at onset and more severe lifetime OCD symptoms, poorer insight, more difficulty making decisions and completing tasks, and more overall impairment. The hoarding group also had a greater lifetime prevalence of panic disorder, specific phobia, Tourette disorder, and tics. As measured with the Social Reciprocity Scale, the hoarding group had more severe deficits in parent-rated domains of social communication, social motivation, and restricted interests and repetitive behavior. In a multivariable model, the overall social reciprocity score, age at onset of OCD symptoms, symmetry obsessions, and indecision were independently related to hoarding in these children and adolescents with OCD. These features should be considered as candidate risk factors for the development of hoarding behavior in pediatric OCD.

Background: Success of heart transplantation is affected by allograft rejection, which is known as a lymphocyte-mediated process. Recent studies suggest that neutrophils contribute to this process. We hypothesized that the severity of cardiac rejection can be predicted by evaluating an individual's neutrophil transendothelial migration potential, which can be assessed through artificial stimulation of neutrophils., Methods: Eleven patients were recruited from the active heart transplant list. Pre-operative blood samples were stained with neutrophil adhesion molecule (CD11b, CD62L, and PSGL-1) antibodies before and after in vitro stimulation with phorbol 12-myristate 13-acetate (PMA; 1 ng/ml) and lipopolysaccharide (LPS 1 microg/ml), and assessed using flow cytometry. Stimulated neutrophil responses were correlated with rejection grade of the first endomyocardial biopsy sampled 10 days post-operatively., Results: Neutrophil adhesion molecules are upregulated after artificial stimulation. Pre-operative neutrophil surface CD11b expression after in vitro lipopolysaccharide stimulation correlated with rejection grade detected in the first endomyocardial biopsy sample (R = 0.677; p = 0.022)., Conclusion: Pre-operative neutrophil response to in vitro stimuli predicted the rejection grade in the first post-transplant endomyocardial biopsy specimen, suggesting that neutrophils may contribute more to cardiac allograft rejection than previously thought.

Carboxylesterases are enzymes that catalyze the hydrolysis of ester and amide moieties. These enzymes have an active site that is composed of a nucleophile (Ser), a base (His), and an acid (Glu) that is commonly known as a catalytic triad. It has previously been observed that the majority of carboxylesterases and lipases contain a second conserved serine in their active site [Proteins, 34 (1999) 184]. To investigate whether this second serine is also involved in the catalytic mechanism, it was mutated to an alanine, a glycine or a cysteine. Site-directed mutagenesis of this conserved serine resulted in a loss of specific activity, in both the S247G and S247A mutants (5- to 15-fold), which was due to a decrease in the rate of catalysis (kcat). Due to the instability of the S247C mutant no reliable data could be attained. A carbamate inhibitor, carbaryl, was then employed to investigate whether this decrease in the kcat was due to the rate of formation of the acyl-enzyme intermediate (k2) or the rate of deacylation (k3). The S247A mutant was found only to alter k2 (2.5-fold decrease), with no effect on k3. Together with information inferred from a human carboxylesterase crystal structure, it was concluded that this serine provides an important structural support for the spatial orientation of the glutamic acid, stabilizing the catalytic triad so that it can perform the hydrolysis.

Background: Investigators have reported lack of normal asymmetry of lateralization in some schizophrenic patients, as measured postmortem and by preference and/or performance. It has been suggested that this lack of asymmetry is related to early onset of schizophrenia. The present study extends the inquiry by magnetic resonance imaging (MRI) measurement of volumetric asymmetry., Methods: Hemispheric asymmetry of volume in regional gray matter was examined in 16 schizophrenic patients who had undergone MRI of brain volume., Results: Low levels of hemispheric asymmetry in the frontal and temporal areas were strongly associated with early onset of schizophrenia, the association with frontal volume being more marked than with temporal volume. No relationship was found in the other brain areas that were scanned. The findings were not artifacts of chronological age, nor of extreme scores in a small sample., Conclusions: These findings are consistent with the hypothesis that failure to develop asymmetry is an important component of the pathology underlying some forms of schizophrenia.

In a group of schizophrenic patients, magnetic resonance imaging (MRI) measures of relative frontal brain volume (total frontal volume/total cerebral volume) correlated highly with the capacity to use context as an aid to recall in a verbal memory task. The dorsolateral area of the prefrontal cortex appears to have contributed most to this effect. Recall of simple word lists without contextual features revealed no correlation with relative frontal volume. With increasing contextual organization of the material, correlations between frontal volume and recall scores increased significantly. These findings are consistent with the general proposition that impairment in the use of informational redundancy is a significant component of schizophrenic pathology.

A laboratory measure of synchronization was used to assess the differential ability of schizophrenics, affectives, and normal controls to take advantage of stimulus predictability. It was hypothesized that (1) schizophrenics will perform on this task in a way that distinguishes them from other groups, (2) clinically observed motor anomalies will be associated with deficient motor synchrony, and (3) deficient motor synchrony will be associated with more severe clinical ratings of thought disorder. Twenty-one schizophrenic, 8 affective, and 16 normal controls were studied. The results were consistent with the hypotheses; schizophrenic subjects had distinctive performance patterns, especially at 40 bpm, which was associated with both motor and thinking disturbance. The authors discuss additional analyses that suggest that deficient motor synchrony is associated with negative symptoms, certain ward behaviors, and not with demographic variables, and that among unmedicated schizophrenic subjects, the performance patterns are worse.