Valvuloplasty in 103 fetuses with critical aortic stenosis: outcome and new predictors for postnatal circulation.

OBJECTIVES: To review our experience with fetal aortic valvuloplasty (FAV) in fetuses with critical aortic stenosis (CAS) and evolving hypoplastic left heart syndrome (eHLHS), including short- and medium-term postnatal outcome, and to refine selection criteria for FAV by identifying preprocedural predictors of biventricular (BV) outcome. METHODS: This was a retrospective review of all fetuses with CAS and eHLHS undergoing FAV at our center between December 2001 and September 2020. Echocardiograms and patient charts were analyzed for pre-FAV ventricular and valvular dimensions and hemodynamics and for postnatal procedures and outcomes. The primary endpoints were type of circulation 28 days after birth and at 1 year of age. Classification and regression-tree analysis was performed to investigate the predictive capacity of pre-FAV parameters for BV circulation at 1 year of age. RESULTS: During the study period, 103 fetuses underwent 125 FAVs at our center, of which 87.4% had a technically successful procedure. Technical success per fetus was higher in the more recent period (from 2014) than in the earlier period (96.2% (51/53) vs 78.0% (39/50); P = 0.0068). Eighty fetuses were liveborn after successful intervention and received further treatment. BV outcome at 1 year of age was achieved in 55% of liveborn patients in our cohort after successful FAV, which is significantly higher than the BV-outcome rate (23.7%) in a previously published natural history cohort fulfilling the same criteria for eHLHS (P = 0.0015). Decision-tree analysis based on the ratio of right to left ventricular (RV/LV) length combined with LV pressure (mitral valve regurgitation maximum velocity (MR-Vmax)) had a sensitivity of 96.97% and a specificity of 94.44% for predicting BV outcome without signs of pulmonary arterial hypertension at 1 year of age. The highest probability for a BV outcome was reached for fetuses with a pre-FAV RV/LV length ratio of < 1.094 (96.4%) and for those fetuses with a RV/LV length ratio ≥ 1.094 to < 1.135 combined with a MR-Vmax of ≥ 3.14 m/s (100%). CONCLUSIONS: FAV could be performed with high success rates and an acceptable risk with improving results after a learning curve. Pre-FAV RV/LV length ratio combined with LV pressure estimates were able to predict a successful BV outcome at 1 year of age with high sensitivity and specificity. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Evolutionary dynamics of residual disease in human glioblastoma.

BACKGROUND: Glioblastoma is the most common and aggressive adult brain malignancy against which conventional surgery and chemoradiation provide limited benefit. Even when a good treatment response is obtained, recurrence inevitably occurs either locally (∼80%) or distally (∼20%), driven by cancer clones that are often genomically distinct from those in the primary tumour. Glioblastoma cells display a characteristic infiltrative phenotype, invading the surrounding tissue and often spreading across the whole brain. Cancer cells responsible for relapse can reside in two compartments of residual disease that are left behind after treatment: the infiltrated normal brain parenchyma and the sub-ventricular zone. However, these two sources of residual disease in glioblastoma are understudied because of the difficulty in sampling these regions during surgery. PATIENT AND METHODS: Here, we present the results of whole-exome sequencing of 69 multi-region samples collected using fluorescence-guided resection from 11 patients, including the infiltrating tumour margin and the sub-ventricular zone for each patient, as well as matched blood. We used a phylogenomic approach to dissect the spatio-temporal evolution of each tumour and unveil the relation between residual disease and the main tumour mass. We also analysed two patients with paired primary-recurrence samples with matched residual disease. RESULTS: Our results suggest that infiltrative subclones can arise early during tumour growth in a subset of patients. After treatment, the infiltrative subclones may seed the growth of a recurrent tumour, thus representing the 'missing link' between the primary tumour and recurrent disease. CONCLUSIONS: These results are consistent with recognised clinical phenotypic behaviour and suggest that more specific therapeutic targeting of cells in the infiltrated brain parenchyma may improve patient's outcome.

Immediate effects and outcome of in-utero pulmonary valvuloplasty in fetuses with pulmonary atresia with intact ventricular septum or critical pulmonary stenosis.

OBJECTIVE: To assess the immediate effects of fetal pulmonary valvuloplasty on right ventricular (RV) size and function as well as in-utero RV growth and postnatal outcome. METHODS: Patients with pulmonary atresia with intact ventricular septum (PAIVS) or critical pulmonary stenosis (CPS) who underwent fetal pulmonary valvuloplasty at our center between October 2000 and July 2017 were included. Echocardiographic data obtained before and after the procedure were analyzed retrospectively (median interval after intervention, 1 (range, 1-3) days) for ventricular and valvular dimensions and ratios, RV filling time (duration of tricuspid valve (TV) inflow/cardiac cycle length), TV velocity time integral (TV-VTI) × heart rate (HR) and tricuspid regurgitation (TR) velocity. Longitudinal data were collected from only those fetuses followed up in our center. Outcome was assessed using the scoring system as described by Roman et al. for non-biventricular outcome. RESULTS: Thirty-five pulmonary valvuloplasties were performed in our institution on 23 fetuses with PAIVS (n = 15) or CPS (n = 8). Median gestational age at intervention was 28 + 4 (range, 23 + 6 to 32 + 1) weeks. No fetal death occurred. Immediately after successful intervention, RV/left ventricular length (RV/LV) ratio (P ≤ 0.0001), TV/mitral valve annular diameter (TV/MV) ratio (P ≤ 0.001), RV filling time (P ≤ 0.00001) and TV-VTI × HR (P ≤ 0.001) increased significantly and TR velocity (P ≤ 0.001) decreased significantly. In fetuses followed longitudinally to delivery (n = 5), RV/LV and TV/MV ratios improved further or remained constant until birth. Fetuses with unsuccessful intervention (n = 2) became univentricular, all others had either a biventricular (n = 15), one-and-a-half ventricular (n = 3) or still undetermined (n = 3) outcome. Five of nine fetuses with a predicted non-biventricular outcome, in which the procedure was successful, became biventricular, while two of nine had an undetermined circulation. CONCLUSION: In selected fetuses with PAIVS or CPS, in-utero pulmonary valvuloplasty led immediately to larger RV caused by reduced afterload and increased filling, thus improving the likelihood of biventricular outcome even in fetuses with a predicted non-biventricular circulation. © 2018 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

Fetal aortic valvuloplasty: investigating institutional bias in surgical decision-making.

OBJECTIVES: Fetal aortic valvuloplasty may prevent the progression of aortic stenosis to hypoplastic left heart syndrome and allow biventricular rather than univentricular postnatal treatment. This study aimed to investigate whether blinded simulation of a multidisciplinary team approach aids interpretation of multicenter data to uncover institutional bias in postnatal decision-making following fetal cardiac intervention for aortic stenosis. METHODS: The study included 109 cases of prenatally diagnosed aortic stenosis from 13 European countries, of which 32 had undergone fetal cardiac intervention. The multidisciplinary team, blinded to fetal cardiac intervention, institutional location and postnatal treatment, retrospectively assigned a surgical pathway (biventricular or univentricular) based on a review of recorded postnatal imaging and clinical characteristics. The team's decisions were the numerical consensus of silent voting, with case review when a decision was split. Funnel plots showing concordance between the multidisciplinary team and the local team's surgical choice (first pathway) and with outcome (final pathway) were created. RESULTS: In 105 cases the multidisciplinary team reached a consensus decision regarding the surgical pathway, with no decision in four cases because the available imaging records were inadequate. Blinded multidisciplinary team consensus for the first pathway matched the decision of the surgical center in 93/105 (89%) cases, with no difference in agreement between those that had undergone successful fetal cardiac intervention (n = 32) and no (n = 74) or unsuccessful (n = 3) valvuloplasty (no fetal cardiac intervention) (κ = 0.73 (95% CI, 0.38-1.00) vs 0.74 (95% CI, 0.51-0.96)). However, funnel plots comparing multidisciplinary team individual decisions with those of the local teams displayed more discordance (meaning biventricular-univentricular conversion) for the final surgical pathway following fetal cardiac intervention than they did for cases without such intervention (36/74 vs 34/130; P = 0.002), and identified one outlying center. CONCLUSIONS: The use of a blinded multidisciplinary team to simulate decision-making and presentation of data in funnel plots may assist in the interpretation of data submitted to multicenter studies and permit the identification of outliers for further investigation. In the case of aortic stenosis, a high level of agreement was observed between the multidisciplinary team and the surgical centers, but one outlying center was identified.

Current and future genomic applications for surgeons.

Genomics is a crucial part of managing surgical disease. This review focuses on some of the genomic advances that are available now and looks to the future of their application in surgical practice. Whole-genome sequencing enables unbiased coverage across the entire human genome of approximately three billion base pairs. Newer technologies, such as those that permit long-read sequence analysis, provide additional information in longer phased fragment and base pair epigenomic (methylomic) data. Whole-genome sequencing is currently available in England for cancers in children, teenagers and young adults, central nervous system tumours, sarcoma and haematological malignancies. Circulating tumour DNA (ctDNA), immunotherapy and pharmacogenomics have emerged as groundbreaking approaches in the field of cancer treatment. These are now revolutionising the way oncologists and surgeons approach curative cancer surgery. Cancer vaccines offer an innovative approach to reducing recurrence after surgery by priming the immune system to trigger an immune response. The Cancer Vaccine Launch Pad project facilitates cancer vaccine studies in England. The BNT122-01 trial is recruiting patients with ctDNA-positive high-risk colorectal cancer after surgery to assess the impact of cancer vaccines. The evolving landscape of cancer treatment demands a dynamic and integrated approach from the surgical multidisciplinary team. Immunotherapy, ctDNA, pharmacogenomics, vaccines, mainstreaming and whole-genome sequencing are just some of the innovations that have the potential to redefine the standards of care. The continued exploration of these innovative diagnostics and therapies, the genomic pathway evolution and their application in diverse cancer types highlights the transformative impact of precision medicine in surgery.

Inactivation of VicK affects acid production and acid survival of Streptococcus mutans.

The regulation of acid production in and the tolerance to low pH of the cariogenic bacterium Streptococcus mutans have garnered considerable attention since both of these properties contribute substantially to the virulence of this organism. Frequent or prolonged exposure to acid end products, mainly lactic acid, that are present following the consumption of dietary sugars erodes the dental enamel, thereby initiating dental caries. Here we report the involvement of the S. mutans VicK sensor kinase in both the acidogenicity and the aciduricity of this bacterium. When cultures were supplemented with glucose, the glycolytic rate of a VicK null mutant was significantly decreased compared to the glycolytic rate of the wild type (P < 0.05), suggesting that there was impaired acid production. Not surprisingly, the VicK deletion mutant produced less lactic acid, while an acid tolerance response assay revealed that loss of VicK significantly enhanced the survival of S. mutans (P < 0.05). Compared to the survival rates of the wild type, the survival rates of the VicK-deficient mutant were drastically increased when cultures were grown at pH 3.5 with or without preexposure to a signal pH (pH 5.5). Global transcriptional analysis using DNA microarrays and S. mutans wild-type UA159 and VicK deletion mutant strains grown at neutral and low pH values revealed that loss of VicK significantly affected expression of 89 transcripts more than twofold at pH 5.5 (P < 0.001). The affected transcripts included genes with putative functions in transport and maintenance of cell membrane integrity. While our results provide insight into the acid-inducible regulon of S. mutans, here we imply a novel role for VicK in regulating intracellular pH homeostasis in S. mutans.

Memory impairment in Korsakoff's psychosis: a correlation with brain noradrenergic activity.

The concentration of the primary brain metabolite of norepinephrine is diminished in the lumbar spinal fluid of patients with Korsakoff's syndrome. The extent of its reduction is significantly correlated with measures of memory impairment for individual patients. These data suggest that the memory disorder of Korsakoff's syndrome may result from damage to ascending noradrenergic pathways by the diencephalic and brainstem lesions associated with this disease.

Involvement of Streptococcus mutans regulator RR11 in oxidative stress response during biofilm growth and in the development of genetic competence.

AIMS: To identify the genes regulated by RR11, the regulator of the Streptococcus mutans HK/RR11 two-component system. METHODS AND RESULTS: The S. mutans RR11-encoding gene was inactivated, and the effects of gene disruption on the cell's ability to form biofilms under stresses and acquire extracellular DNA were tested. Biofilm was reduced in cells lacking RR11 following exposure to oxidative stress. RR11-defective cells showed approx. 20-fold reduction in transformation efficiency. Microarray used to decipher the RR11-regulated genes in biofilm showed that approx. 5% of the UA159 genome underwent a significant change in expression. RR11 was found to regulate 174 genes, including genes involved in competence, stress-response and cell division. CONCLUSIONS: Target genes controlled by RR11during biofilm growth have been identified by a comparison of transcriptional profiles between an RR11 defective mutant and the parental strain. The results demonstrated that RR11 is involved in the control of diverse cellular processes, including the formation of biofilm under oxidative stress and development of genetic competence. SIGNIFICANCE AND IMPACT OF THE STUDY: The regulator of HK/RR11 system controls a large regulon and is an important regulator involved in stress response during S. mutans biofilm growth enabling the survival and persistence of its progeny in the microbial community.

Evaluating an anaerobic digestion (AD) feedstock derived from a novel non-source segregated municipal solid waste (MSW) product.

In many nations industrial scale AD of non-agricultural waste materials (such as MSW) has not yet reached its full potential, often constrained by the lack of secure, inexpensive, high quality AD feedstocks, and markets for the resulting digestate material. We tested the output material of a high throughput novel industrial process to define its potential as an AD feedstock (based on quality and consistency). This process, designed to circumvent the constraints of source segregation while still generating segregated waste streams, resulted in the production of a temporally homogenous fibrous material with: an average moisture content of 44.2 (±2.33)%; C:N ratio of ∼32.9:1 (±3.46:1), C:P ratio of ∼228:1 and gross calorific value of 17.4 (±0.29)MJ/kg(DM). This material provided a CH4 yield of between 201 and 297m3 CH4/tonne(DM) (271-401m3CH4/tonne(vs)) comparable to commonly used AD feedstocks. Material contaminant levels were temporally consistent (P>0.05), (average values being Cd 0.63 (±0.19), Cu 56.3 (±7.45), Crtot 51.4 (±4.41), Hg<0.3, Ni 28.9 (±5.17), Pb 79.2 (±23.71), Zn 202 (±44.5), total polyaromatic hydrocarbons (PAH) 2.2 (±0.3), and total polychlorinated biphenyls (PCB) (<0.2)mg/kg(DM)). Calculated digestate contaminant levels were below the median contaminant threshold limits for anaerobic digestates of all countries within the European Union i.e. of Cd 3.35, Cu 535, Crtot 535, Hg 8.15, Ni 185, Pb 397.5, Zn 2100mg/kg(DM). We suggest that novel high throughput processes that produce high quality AD feedstocks, may have a place in further diversion of waste from landfill.

The Korsakoff syndrome: a neurochemical perspective.

Korsakoff's disease is an amnesic syndrome associated with midline diencephalic and brain stem pathology. A number of neurochemical systems course through or near the loci of brain lesions found postmortem in Korsakoff patients, which has stimulated studies to learn whether these systems are implicated in amnesia. Data suggest that the loss of brain catecholamine function contributes to this amnesic syndrome and may also be a factor in the memory impairments associated with normal aging. At present, data are insufficient to determine whether cholinergic systems are disturbed in Korsakoff's patients; however, it is likely that multiple neurochemical abnormalities underlie this disorder.

A System for Open-Access He Human Lung Imaging at Very Low Field.

We describe a prototype system built to allow open-access very-low-field MRI of human lungs using laser-polarized (3)He gas. The system employs an open four-coil electromagnet with an operational B(0) field of 4 mT, and planar gradient coils that generate gradient fields up to 0.18 G/cm in the x and y direction and 0.41 G/cm in the z direction. This system was used to obtain (1)H and (3)He phantom images and supine and upright (3)He images of human lungs. We include discussion on challenges unique to imaging at 50 -200 kHz, including noise filtering and compensation for narrow-bandwidth coils.

On the role of thalamic pathology in diencephalic amnesia.

Although it is now accepted that medial diencephalic lesions can produce severe amnesia in humans, the specific nuclei and neural pathways that must be damaged to impair memory have not yet been identified. Recent studies have shown that pyrithiamine-induced thiamine deficiency (PTD) in the rat can produce a consistent pattern of pathology in the thalamus and mammillary bodies and result in permanent impairments on behavioral measures of working memory. Behavioral deficits comparable to the PTD model have been observed in rats with thalamic lesions involving lateral portions of the internal medullary lamina (the L-IML site). Such impairments are not observed following lesions of limbic-related pathways associated with the fornix, mammillary bodies, or midline thalamus. The L-IML lesion affects the mediodorsal nucleus (MDn) and both the intralaminar and paralaminar non-specific thalamic nuclei. The relationship between the non-specific thalamic nuclei and working memory is underscored by the limited behavioral effects of MDn lesions, as compared to either L-IML or PTD-induced lesions, and by anatomical analyses of PTD-related pathology, which seems to destroy the non-specific nuclei while sparing large portions of the MDn. Recent physiological studies of thalamocortical processes suggest that there are several possible mechanisms by which the non-specific nuclei might participate in memory and by which lesions in these pathways might interfere with the consolidation of memories within the cortex.

Neurochemical pathology in Korsakoff's psychosis: implications for other cognitive disorders.

There seems to be an anatomic correspondence between pathways of monoamine-containing neurons and the brainstem and diencephalic lesions associated with Korsakoff's psychosis. In 25 patients with Korsakoff's disease, we found that CSF levels of metabolites of norepinephrine, dopamine, and serotonin were significantly lower than in controls. Norepinephrine metabolite levels were reduced more consistently and extensively than those of dopamine and serotonin. The 25 patients had circumscribed cognitive deficits, but were not demented. We argue that norepinephrine-containing neurons are selectively damaged in Korsakoff's psychosis and that lesions of brain monoamine-containing neurons cause specific cognitive impairments, not global dementia.

Multimodal sensory discrimination deficits in Korsakoff's psychosis.

A consistent impairment in odor identification was observed among a group of 21 amnesic patients, diagnosed as having Korsakoff's psychosis. In a subsequent study of eight Korsakoff and matched alcoholic control subjects, a comparable olfactory deficit was again demonstrated, as well as impairment in color discrimination and auditory perception. No such deficit was observed for a picture identification task designed to control for the non-sensory demands of the olfactory test. Stepwise multiple regression analysis showed a significant correlation between odor identification scores and the concentration of the primary metabolite of norepinephrine in lumbar cerebrospinal fluid. The data demonstrate a consistent coincidence between memory impairment and deficient sensory perception among patients with Korsakoff's psychosis.

Response properties of mitral cells in the olfactory bulb of the neonatal rat.

Activity was recorded from mitral cells in newborn to six-day-old rat pups during odorous stimulation. Twenty-eight neurons were studied in pups with unopened nasal cavities which sampled stimuli during intermittent periods of inhalation. Forty-six neurons were studied in pups with opened nasal cavities which were stimulated by delivering odorants directly to the olfactory epithelia. We show that mitral cells are selectively excited by different odorants on the day pups are born; prior to the maturation of bulb interneurons, the responses of neonatal mitral cells are time-locked to the inhalation cycle; neonatal mitral cells preserve the temporal patterns of activity exhibited by receptor neurons during stimulation with different concentrations of odorants; and the response patterns of mitral cells differ qualitatively between newborn and adult rats. We conclude that receptor-to-mitral cell synapses are functional in newborn rat pups and that the activity of this afferent pathway is modulated by the pups' respiratory behavior. We argue that without interneurons, mitral cells repeat the temporal code exhibited by receptor neurons and do not produce the types of response patterns characteristic of neurons in the adult rat olfactory bulb.

Postnatal proliferation and maturation of olfactory bulb neurons in the rat.

Mitral cells are formed prenatally whereas most granule cells originate postnatally. Material was taken from 2-day-old, 14-day-old, 28-day-old, and adult rat olfactory bulbs and processed for rapid Golgi or Cresyl Violet staining. We show that the number of granule cell bodies/mitral cell body increases from 7.0 to 46.3 during the first two weeks of life; most mitral cells appear morphologically functional during the first postnatal week; few granule cells appear to be functional until the second postnatal week; and the number of short axon interneurons increases dramatically during the second postnatal week. We conclude the newborn rats have an intact afferent pathway from olfactory receptors to primary cortex that lacks the extensive interneuronal circuitry characteristic of adults.

Changes in morphology and physiology of olfactory receptor cilia during development.

Ciliated olfactory receptor neurons in vertebrates turn over throughout life. We show that these neurons bear different types of cilia at different developmental stages; cilia on newly differentiating cells are short and motile; cilia on mature cells are longer and immotile; Mg2+ and adenosine 5'-triphosphate are requisite for ciliary motion; stimulation with odorants can induce synchronous motion and that this process is mediated by Ca2+. We propose that receptor neurons have two distinguishable developmental states. In the first, before the growing axon establishes synaptic connection to the brain, the cells bear motile cilia and are generally irritable. In the second, the cilia are long and immotile and the cells can distinguish between odorants.

Bilateral nephrectomy: the best, but often overlooked, treatment for refractory hypertension in hemodialysis patients.

Bilateral nephrectomy for treatment of refractory hypertension in chronic hemodialyzed patients has been infrequently carried out. We analyzed the benefits of this operation on blood pressure, clinical state, drug treatment, and quality of life. In 10 hemodialyzed patients with refractory hypertension, systolic (SBP) and diastolic (DBP) blood pressure were measured 1 month before nephrectomy bilateral and 3, 6, 9, and 12 months after. In addition, the use of antihypertensive drugs before and after surgery was evaluated. Four patients had SBP and DBP values characteristic of malignant hypertension. In all 10 patients hypertension responded neither to reduction of plasma volume by ultrafiltration nor to multiple antihypertensive drug therapy. Hypertensive crises were associated with cerebral hemorrhage in two patients, severe encephalopathy with persistent neural dysfunction in one patient, and encephalopathy and diplopia in another. Three months after bilateral nephrectomy blood pressure decreased significantly (P < .005) and was normal in nine patients. In one noncompliant patient with intradialytic body weight increases of nearly 10%, blood pressure was still elevated. Malignant or drug-resistant hypertension with hypertensive crises is an indication for bilateral nephrectomy. The clinical state and quality of life improved in all patients in the present study and antihypertensive treatment is no longer necessary.

Radio-frequency lesions of the thalamus produce delayed-nonmatching-to-sample impairments comparable to pyrithiamine-induced encephalopathy in rats.

Rats were trained and matched on a delayed-nonmatching-to-sample (DNMTS) task and randomly assigned to treatment. In Experiment 1, radio-frequency (RF) lesions were aimed at lateral portions of the internal medullary lamina (L-IML), midline thalamus (MT), mammillary bodies (MB), and the combination of MT and MB. In Experiment 2, RF lesions were aimed at the fornix. After recovery, DNMTS was retrained at retention intervals retention interval of 3.0-18.0 s, the critical retention interval for 75% DNMTS accuracy was determined by a staircase procedure, and spontaneous exploration was observed in an open field. L-IML lesions produced significant deficits on DNMTS and exploratory behavior that were comparable to deficits on the same tasks in rats recovered from pyrithiamine-induced thiamine deficiency. Fornix lesions produced significant DNMTS deficits that were substantially smaller than for the L-IML group. The MT, MB, and MT+MB treatments had no significant effect on DNMTS.

Depletion of cortical norepinephrine in rats by 6-hydroxydopamine does not impair performance of a delayed-nonmatching-to-sample task.

Rats were trained on a spatial delayed-nonmatching-to-sample (DNMTS) task, matched for performance, and randomly assigned to treatment with dorsal noradrenergic bundle injections of either 6-hydroxydopamine, to deplete cortical norepinephrine (NE), or vehicle, to control for the effects of surgery. After recovery, there were no significant differences between the groups when retrained on the DNMTS task at retention intervals (RI) from 0.1 to 15.0 s. Furthermore, no differences were observed when rats were trained at a 6.0-s RI filled with distracting stimuli or when dummy information runs were added to increase proactive interference. These results demonstrate that depletion of cortical NE cannot account for the DNMTS performance deficits observed in rats recovered from pyrithiamine-induced thiamine deficiency (Knoth & Mair, 1991; Robinson & Mair, 1992).