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BACKGROUND COVID-19 was first reported in 2019, and the Chinese government immediately carried out stringent and effective control measures in response to the epidemic. OBJECTIVE Nonpharmaceutical interventions (NPIs) may have impacted incidences of other infectious diseases as well. Potential explanations underlying this reduction, however, are not clear. Hence, in this study, we aim to study the influence of the COVID-19 prevention policies on other infectious diseases (mainly class B infectious diseases) in China. METHODS Time series data sets between 2017 and 2021 for 23 notifiable infectious diseases were extracted from public data sets from the National Health Commission of the People’s Republic of China. Several indices (peak and trough amplitudes, infection selectivity, preferred time to outbreak, oscillatory strength) of each infectious disease were calculated before and after the COVID-19 outbreak. RESULTS We found that the prevention and control policies for COVID-19 had a strong, significant reduction effect on outbreaks of other infectious diseases. A clear event-related trough (ERT) was observed after the outbreak of COVID-19 under the strict control policies, and its decreasing amplitude is related to the infection selectivity and preferred outbreak time of the disease before COVID-19. We also calculated the oscillatory strength before and after the COVID-19 outbreak and found that it was significantly stronger before the COVID-19 outbreak and does not correlate with the trough amplitude. CONCLUSIONS Our results directly demonstrate that prevention policies for COVID-19 have immediate additional benefits for controlling most class B infectious diseases, and several factors (infection selectivity, preferred outbreak time) may have contributed to the reduction in outbreaks. This study may guide the implementation of nonpharmaceutical interventions to control a wider range of infectious diseases.

Purpose. We investigated the disparate influence of lesion location on functional damage and reorganization of the sensorimotor brain network in patients with thalamic infarction and pontine infarction. Methods. Fourteen patients with unilateral infarction of the thalamus and 14 patients with unilateral infarction of the pons underwent longitudinal fMRI measurements and motor functional assessment five times during a 6-month period (

We aimed to investigate the possible factors associated with the occurrence of crossed cerebellar diaschisis (CCD) at the hyperacute stage of ischemic stroke using whole-brain volume perfusion CT (VPCT) combined with magnetic resonance imaging (MRI). We retrospectively analyzed 108 patients with ischemic stroke within 6 h of onset. The VPCT findings of the patients showed a unilateral perfusion deficit in the supratentorial territory. Follow-up MRI examinations were performed within 24 h after onset. The effects of the supratentorial cerebral ischemia, the location distribution, the final infarct volume and the apparent diffusion coefficient (ADC) value on the occurrence and severity of CCD were analyzed. Among 108 patients with hyperacute cerebral ischemia, 62 (57.4%) demonstrated a contralateral cerebellar perfusion deficit on the VPCT maps. The occurrence of CCD was related to a reduction in cerebral blood volume (CBV) and prolongation of the mean transit time (MTT). Notably, the decrease in the ADC value in the infarct based on follow-up MRI was closely related to the occurrence and severity of CCD. The occurrence and severity of CCD are related to the degree of low supratentorial perfusion and the decrease in the ADC value of infarct focus.

OBJECTIVE: To investigate the clinical efficacy of computer-assisted cannulated screw internal fixation system based on error correction method for femoral neck fractures. METHODS: A retrospective analysis was made on the clinical data of 20 femoral neck fracture patients treated by computer-assisted cannulated screw internal fixation system based on error correction method between January 2014 and October 2015 (trial group), and 36 femoral neck fracture patients undergoing traditional manual surgery with closed reduction by cannulated screw fixation in the same period (the control group). There was no significant difference in gender, age, injury cause, side of fracture, types of fracture, and time from injury to operation between 2 groups (P>0.05). The operation time, intraoperative blood loss, intraoperative frequency of fluoroscopy and guide pin insertion, fracture healing time, fracture healing rate, and Harris hip score were compared between 2 groups. RESULTS: All incisions healed by first intention after operation, and no complication of blood vessel and nerve injury occurred. The operation time of trial group was significantly longer than that of control group (t=2.290, P=0.026), however, the intraoperative blood loss, intraoperative frequency of fluoroscopy and guide pin insertion of trial group were significantly less than those of control group (t=–10.650, P=0.000; t=18.320, P=0.000; t=–16.625, P=0.000). All patients were followed up 12-18 months (mean, 14.7 months). X-ray films showed that fracture healing was obtained in 2 groups, showing no significant difference in fracture healing time between 2 groups (t=0.208, P=0.836). No complication of ischemic necrosis of femoral head occurred during follow-up period. At last follow-up, the Harris hip score was 87.05±3.12 in trial group and was 86.78±2.83 in control group, showing no significant difference (t=0.333, P=0.741). CONCLUSION: Computer-assisted cannulated screw internal fixation surgery based on error correction method for femoral neck fractures is better than traditional manual surgery in decreasing intraoperative radiation and surgical trauma during operation.

Modern molecular methods offer the advantages of simplicity and short time-to-results compared to traditional culture methods. We describe the validation of a new Real-Time PCR method to detect E. coli O157:H7 in five food matrixes. The complete system consists of the MicroSEQ®E. coli O157:H7 Detection Kit, sample preparation (two sample preparation methods, the PrepSEQ® Nucleic Acid Extraction Kit and the PrepSEQ Rapid Spin Sample Preparation Kit, were validated), the Applied Biosystems 7500 Fast Real-Time PCR instrument, and RapidFinder™ Express software. The test method was compared to the U.S. Department of Agriculture Microbiology Laboratory Guidebook 5.04 reference method for detecting E. coli O157:H7 in 25 g and 375 g ground beef and beef trim, and to the ISO 16654 reference method for detecting E. coli O157:H7 in 25 g spinach, orange juice, and apple juice. The MicroSEQ E. coli O157:H7 Detection Kit showed equivalent detection compared to the corresponding reference method based on Mantel-Haenszel Chi-square statistics for all matrixes tested. An independent validation confirmed these findings on ground beef. The MicroSEQ kit detected all 51 E. coli O157:H7 strains tested and showed good discrimination against an exclusivity panel of 30 strains.

A complete system for real-time PCR detection of Listeria species was validated in five food matrixes and five environmental surfaces, namely, hot dogs, roast beef, lox (smoked salmon), pasteurized whole cow's milk, dry infant formula, stainless steel, plastic cutting board, ceramic tile, rubber sheets, and sealed concrete. The system consists of the MicroSEQ®Listeria spp. Detection Kit, two sample preparation kits (PrepSEQ® Nucleic Acid Extraction Kit and PrepSEQ Rapid Spin Sample Preparation Kit), the Applied Biosystems 7500 Fast Real-Time PCR instrument, and the RapidFinder™ Express v1.1 Software for data analysis. The test method was compared to the ISO 11290-1 reference method using an unpaired study design. The MicroSEQ Listeria spp. Detection Kit and the ISO 11290-1 reference method showed equivalent detection based on Chi-square analysis for all matrixes except hot dogs. For hot dogs, the MicroSEQ method detected more positives than the reference method for the low- and high-level inoculations, with all of the presumptive positives confirmed by the reference method. An independent validation study confirmed these findings on lox and stainless steel surface. The MicroSEQ kit detected all 50 Listeria strains tested and none of the 31 nontarget bacteria strains.

Intrinsic functional connectivity detected by functional MRI (fMRI) provides a useful but indirect approach to study the organization of human brain systems. An unresolved question is whether functional connectivity measured by resting-state fMRI reflects anatomical connections. In this study, we used the well-characterized anatomy of cerebrocerebellar circuits to directly test whether intrinsic functional connectivity is associated with an anatomic pathway. Eleven first-episode stroke patients were scanned five times during a period of 6 months, and 11 healthy control subjects were scanned three times within 1 month. In patients with right pontine strokes, the functional connectivity between the right motor cortex and the left cerebellum was selectively reduced. This connectivity pattern was reversed in patients with left pontine strokes. Although factors beyond anatomical connectivity contribute to fMRI measures of functional correlation, these results provide direct evidence that functional connectivity depends on intact connections within a specific polysynaptic pathway.

Increasingly, more food companies are relying on molecular methods, such as PCR, for pathogen detection due to their improved simplicity, sensitivity, and rapid time to results. This report describes the validation of a new Real-Time PCR method to detect Listeria monocytogenes in nine different food matrixes. The complete system consists of the MicroSEQ L. monocytogenes Detection Kit, sample preparation, the Applied Biosystems 7500 Fast Real-Time PCR instrument, and RapidFinder Express software. Two sample preparation methods were validated: the PrepSEQ Nucleic Acid extraction kit and the PrepSEQ Rapid Spin sample preparation kit. The test method was compared to the ISO 11290-1 reference method using an unpaired-study design to detect L. monocytogenes in roast beef, cured bacon, lox (smoked salmon), lettuce, whole cow's milk, dry infant formula, ice cream, salad dressing, and mayonnaise. The MicroSEQ L. monocytogenes Detection Kit and the ISO 11290-1 reference method showed equivalent detection based on Chi-square analysis for all food matrixes when the samples were prepared using either of the two sample preparation methods. An independent validation confirmed these findings on smoked salmon and whole cow's milk. The MicroSEQ kit detected all 50 L. monocytogenes strains tested, and none of the 30 nontargeted bacteria strains.

Increasingly, more food companies are relying on molecular methods, such as PCR, for pathogen detection due to their improved simplicity, sensitivity, and rapid time to results. this report describes the validation of a new Real-time PCR method to detect Listeria monocytogenes in nine different food matrixes. the complete system consists of the MicroSEQ®L. monocytogenes Detection Kit, sample preparation, the Applied Biosystems 7500 Fast Real-time PCR instrument, and RapidFinder™ Express software. two sample preparation methods were validated: the PrepSEQ® Nucleic Acid extraction kit and the PrepSEQ Rapid Spin sample preparation kit. the test method was compared to the ISO 11290-1 reference method using an unpaired-study design to detect L. monocytogenes in roast beef, cured bacon, lox (smoked salmon), lettuce, whole cow's milk, dry infant formula, ice cream, salad dressing, and mayonnaise. the MicroSEQ L. monocytogenes Detection Kit and the ISO 11290-1 reference method showed equivalent detection based on Chi-square analysis for all food matrixes when the samples were prepared using either of the two sample preparation methods. An independent validation confirmed these findings on smoked salmon and whole cow's milk. the MicroSEQ kit detected all 50 L. monocytogenes strains tested, and none of the 30 nontargeted bacteria strains.

Real-time PCR methods for detecting foodborne pathogens offer the advantages of simplicity and quick time-to-results compared to traditional culture methods. In this study, the MicroSEQ® real-time PCR system was evaluated for detection of Salmonella spp. in 10 different food matrixes following the AOAC Research Institute's Performance Tested MethodSM validation program. In addition, the performance of the MicroSEQ system was evaluated for the detection of Salmonella in peanut butter as a part of the Emergency Response Validation Program sponsored by the AOAC Research Institute. The system was compared to the ISO 6579 reference method using a paired-study design for detecting Salmonella spp. in raw ground beef, raw chicken, raw shrimp, Brie cheese, shell eggs, cantaloupe, chocolate, black pepper, dry infant formula, and dry pet food. For the peanut butter study, the system was compared to the U.S. Food and Drug Administration's Bacteriological Analytical Manual procedures using an unpaired-study design. No significant difference in performance was observed between the MicroSEQ Salmonella spp. detection system and the corresponding reference methods for all 11 food matrixes. The MicroSEQ system detected all Salmonella strains tested, while showing good discrimination against detection of an exclusivity panel of 30 strains, with high accuracy.

Context.—Expression profiling by microarrays and real-time polymerase chain reaction–based assays is a powerful tool for classification and prognostication of disease; however, it remains a research tool, largely reliant on frozen tissue. Limiting the utility of expression profiling is the isolation of quality nucleic acids from formalin-fixed, paraffin-embedded tissue. The collection, handling, and processing of tissue directly impacts the biomolecules that can be recovered from it. High-quality nucleic acids can be obtained from formalin-fixed, paraffin-embedded tissue, but greater attention to all steps in the process of tissue handling and preparation is required.Objective.—To summarize the current state-of-the-art of preanalytic factors in tissue handling and processing as they impact the quality of RNA obtainable from formalin-fixed, paraffin-embedded tissue. The goals are to provide recommendations that will improve RNA quality for expression profiling from formalin-fixed, paraffin-embedded tissue and highlight areas for additional research. Tissue is an analyte and it must be handled in a standardized fashion to provide consistent results.Data Sources.—The literature was reviewed. Consultation with industry and academic leaders in the use of RNA for expression profiling was obtained to identify areas for additional research.Conclusions.—Development of RNA-based assays from formalin-fixed, paraffin-embedded tissue is feasible. Greater attention to tissue handing and processing is essential to improve the quality of biospecimens for the development of robust RNA-based assays. Standardization of procedures and vigorous testing of alternative protocols are required to ensure that these assays function as designed.

The extraordinary cellular heterogeneity of the mammalian nervous system has largely hindered the molecular analysis of neuronal identity and diversity. In order to uncover mechanisms involved in neuronal differentiation and diversification, we have monitored the expression profiles of individual neurons and progenitor cells collected from dissociated tissue or captured from intact slices. We demonstrate that this technique provides a sensitive and reproducible representation of the single-cell transcriptome. In the olfactory system, hundreds of transcriptional differences were identified between olfactory progenitors and mature sensory neurons, enabling us to define the large variety of signaling pathways expressed by individual progenitors at a precise developmental stage. Finally, we show that regional differences in gene expression can be predicted from transcriptional analysis of single neuronal precursors isolated by laser capture from defined areas of the developing brain.

Ca2+ currents in acutely isolated, adult rat neostriatal neurons were studied with whole-cell voltage-clamp techniques. In the vast majority of neurons (approximately 90%, n > 250), currents were exclusively of the high-voltage-activated (HVA) type. HVA currents activated near -40 mV and reached their maximum amplitude near 0 mV. Quasi-steady-state inactivation curves in many neurons were well fitted only with a sum of Boltzmann functions, suggesting that the HVA currents were heterogeneous. Although the block of whole-cell current by Cd2+ was well fitted with a single isotherm having an IC50 of near 1 microM, experiments with organic channel antagonists suggested that at least four types of HVA channels were expressed by most cells. On average, the L-channel antagonist nifedipine (5–10 microM) blocked 31 +/- 10% of the whole-cell current (n = 20), the N-channel antagonist omega- conotoxin GVIA (omega-CgTx) (2–5 microM) blocked 27 +/- 11% (n = 20), and the P-channel antagonist omega-agatoxin IVA (100–500 nM) blocked 21 +/- 10% (n = 18). In many neurons, the block by omega-CgTx was partially or completely reversible. In cells tested with a combination of these antagonists, 34 +/- 17% of the peak Ca2+ current remained unblocked (n = 13). Single-cell expression profiling of medium-sized neurons revealed the presence of rbA and rbB Ca2+ channel alpha 1 subunit mRNAs but low or undetectable levels of rbC mRNA (n = 12). These findings suggest that although adult neostriatal projection neurons do not express significant levels of LVA Ca2+ current, they do express a pharmacologically and structurally heterogeneous population of HVA currents.

Real-time PCR methods for detecting foodborne pathogens offer the advantages of simplicity and quick time-to-results compared to traditional culture methods. In this study, the MicroSEQ real-time PCR system was evaluated for detection of Salmonella spp. in 10 different food matrixes following the AOAC Research Institute's Performance Tested Method validation program. In addition, the performance of the MicroSEQ system was evaluated for the detection of Salmonella in peanut butter as a part of the Emergency Response Validation Program sponsored by the AOAC Research Institute. The system was compared to the ISO 6579 reference method using a paired-study design for detecting Salmonella spp. in raw ground beef, raw chicken, raw shrimp, Brie cheese, shell eggs, cantaloupe, chocolate, black pepper, dry infant formula, and dry pet food. For the peanut butter study, the system was compared to the U.S. Food and Drug Administration's Bacteriological Analytical Manual procedures using an unpaired-study design. No significant difference in performance was observed between the MicroSEQ Salmonella spp. detection system and the corresponding reference methods for all 11 food matrixes. The MicroSEQ system detected all Salmonella strains tested, while showing good discrimination against detection of an exclusivity panel of 30 strains, with high accuracy.

Dopaminergic neurons of the substantia nigra provide one of the major neuromodulatory inputs to the neostriatum. Recent in situ hybridization experiments have suggested that postsynaptic dopamine receptors are segregated in striatonigral and striatopallidal neurons. We have tested this hypothesis in acutely isolated, retrogradely labeled striatonigral neurons by examining the neuromodulatory effects of selective dopaminergic agonists on Na currents and by probing single-cell antisense RNA populations with dopamine receptor cDNAs. In most of the neurons examined (20/31), the application of the D1 dopamine receptor agonist SKF 38393 reduced evoked whole-cell Na+ current. The D2 agonists quinpirole and bromocriptine had mixed effects; in most neurons (23/42), whole-cell Na+ currents were reduced, but in others (8/42), currents were increased. In cell-attached patch recordings, bath application of SKF 38393 decreased currents as in whole-cell recordings, whereas quinpirole consistently (6/10) enhanced currents--suggesting that D2-like receptors could act through membrane delimited and non-delimited pathways. Changes in evoked current were produced by modulation of peak conductance and modest shifts in the voltage dependence of steady-state inactivation. Antisense RNA probes of dopamine receptor cDNA Southern blots consistently (5/5) revealed the presence of D1, D2, and D3 receptor mRNA in single striatonigral neurons. These findings argue that, contrary to a strict receptor segregation hypothesis, many striatonigral neurons colocalize functional D1, D2, and D3 receptors.

We present here a method for broadly characterizing single cells at the molecular level beyond the more common morphological and transmitter/receptor classifications. The RNA from defined single cells is amplified by microinjecting primer, nucleotides, and enzyme into acutely dissociated cells from a defined region of rat brain. Further processing yields amplified antisense RNA. A second round of amplification results in greater than 10(6)-fold amplification of the original starting material, which is adequate for analysis--e.g., use as a probe, making of cDNA libraries, etc. We demonstrate this method by constructing expression profiles of single live cells from rat hippocampus. This profiling suggests that cells that appear to be morphologically similar may show marked differences in patterns of expression. In addition, we characterize several mRNAs from a single cell, some of which were previously undescribed, perhaps due to "rarity" when averaged over many cell types. Electrophysiological analysis coupled with molecular biology within the same cell will facilitate a better understanding of how changes at the molecular level are manifested in functional properties. This approach should be applicable to a wide variety of studies, including development, mutant models, aging, and neurodegenerative disease.

The application of microarray technologies to the brain poses unique challenges, because of the complexity of the central nervous system and the availability of resources. Nevertheless, recent studies using DNA chips have made inroads into the molecular characterization of regional and functional brain units, the identification of developmental gene expression patterns, and the discovery of transcriptional differences associated with behavioral and neuropathological traits.

With the completion of the first draft of human genomic consensus sequence, there is a predicable increase in interest concerning the types and amount of genetic diversity in the human population. The most abundant type of variations are single nucleotide polymorphisms (SNPs) (Collins et al. 1997). Some of these genetic variations underpin the genetic basis for disease susceptibility and are used in genetic studies as markers for complex traits and diseases. High-density variation detection arrays (VDAs) have been successfully used for large-scale SNP screening (Chee et al. 1996; Wang et al. 1998; Cargill et al. 1999; Hacia et al. 1999; Halushka et al. 1999). In these experiments, predetermined DNA targets within the genome were amplified with specific PCR reactions. To discover SNPs in this way, each locus in the genome needs to be amplified individually. Although multiple loci can be amplified in a multiplex PCR, this multiplexing approach is costly and labor intensive in the development stages and difficult to scale. In this study, high-density oligonucleotide arrays were used to screen for SNPs from a subset of human genomic DNA. Each subset of genomic DNAs contained a complexity up to 10 Mb and was amplified with one primer in a single PCR reaction. Sequence variations were screened with the same efficiency as individually amplified targets by hybridizing the same complex genomic sample to multiple designs of VDA. In addition, the SNP candidates were validated by using dideoxynucleotide sequencing and by using a bead-based affinity method to enrich fragments that contained candidate SNPs followed by reanalyzing these enriched fragments in a second round of VDA analysis.

We have analyzed the developmental molecular programs of the mouse hippocampus, a cortical structure critical for learning and memory, by means of large-scale DNA microarray techniques. Of 11,000 genes and expressed sequence tags examined, 1,926 showed dynamic changes during hippocampal development from embryonic day 16 to postnatal day 30. Gene-cluster analysis was used to group these genes into 16 distinct clusters with striking patterns that appear to correlate with major developmental hallmarks and cellular events. These include genes involved in neuronal proliferation, differentiation, and synapse formation. A complete list of the transcriptional changes has been compiled into a comprehensive gene profile database ( http://BrainGenomics.Princeton.edu ), which should prove valuable in advancing our understanding of the molecular and genetic programs underlying both the development and the functions of the mammalian brain.

Publisher Summary The ability of neurons in the central nervous system (CNS) to alter their synaptic configuration in response to external stimuli is called “neuronal plasticity.” Plasticity, which occurs during development as the organization of the brain is established and during adult life as changes that underlie learning and memory, is regulated by various factors that ultimately influence cellular physiology. This chapter shows the way changes in gene expression can be correlated with electrophysiological and anatomical studies, the way coordinated changes in gene expression can be monitored, and the way the subcellular compartmentalization of mRNAs may be involved in plasticity-related responses. The techniques of molecular biology is used to study these issues in cultured striatal cells, cultured hippocampal cells, and hippocampal cells in the live slice preparation. Different physiologies are assessed in these experiments. The studies described in the chapter were facilitated through the development of amplified antisense RNA technology.