Fast digital refocusing Fourier ptychographic microscopy method based on convolutional neural network

Fourier ptychographic microscopy (FPM) is used to achieve high resolution and a large field of view. However, traditional FPM image reconstruction methods often yield poor image quality when encountering out-of-focus issues during reconstruction. Therefore, this study proposes a defocus-distance regression network based on convolutional neural networks. In an experimental validation, the root-mean-square error calculated from 1000 sets of predicted and true values was approximately 6.2 µm. The experimental results suggest that the proposed method has good generalization, maintains high accuracy in predicting defocus distances even for different biological samples, and extends the imaging depth-of-field of the FPM system by a factor of more than 3.

Fast Fourier ptychographic quantitative phase microscopy for in vitro label-free imaging

Quantitative phase microscopy (QPM) is indispensable in biomedical research due to its advantages in unlabeled transparent sample thickness quantification and obtaining refractive index information. Fourier ptychographic microscopy (FPM) is among the most promising QPM methods, incorporating multi-angle illumination and iterative phase recovery for high-resolution quantitative phase imaging (QPI) of large cell populations over a wide field of-view (FOV) in a single pass. However, FPM is limited by data redundancy and sequential acquisition strategies, resulting in low imaging efficiency, which in turn limits its real-time application in in vitro label-free imaging. Here, we report a fast QPM based on Fourier ptychography (FQP-FPM), which uses an optimized annular downsampling and parallel acquisition strategy to minimize the amount of data required in the front end and reduce the iteration time of the back-end algorithm (3.3% and 4.4% of conventional FPM, respectively). Theoretical and data redundancy analyses show that FQP-FPM can realize high-throughput quantitative phase reconstruction at thrice the resolution of the coherent diffraction limit by acquiring only ten raw images, providing a precondition for in vitro label-free real-time imaging. The FQP-FPM application was validated for various in vitro label-free live-cell imaging. Cell morphology and subcellular phenomena in different periods were observed with a synthetic aperture of 0.75 NA at a 10× FOV, demonstrating its advantages and application potential for fast high-throughput QPI.

Fast and robust Fourier ptychographic microscopy with position misalignment correction

Significance

Fourier ptychographic microscopy (FPM) is a new, developing computational imaging technology. It can realize the quantitative phase imaging of a wide field of view and high-resolution (HR) simultaneously by means of multi-angle illumination via a light emitting diode (LED) array, combined with a phase recovery algorithm and the synthetic aperture principle. However, in the FPM reconstruction process, LED position misalignment affects the quality of the reconstructed image, and the reconstruction efficiency of the existing LED position correction algorithms needs to be improved.

Aim

This study aims to improve the FPM correction method based on simulated annealing (SA) and proposes a position misalignment correction method (AA-C algorithm) using an improved phase recovery strategy.

Approach

The spectrum function update strategy was optimized by adding an adaptive control factor, and the reconstruction efficiency of the algorithm was improved.

Results

The experimental results show that the proposed method is effective and robust for position misalignment correction of LED arrays in FPM, and the convergence speed can be improved by 21.2% and 54.9% compared with SC-FPM and PC-FPM, respectively.

Conclusions

These results can reduce the requirement of the FPM system for LED array accuracy and improve robustness.

Adaptive correction method of hybrid aberrations in Fourier ptychographic microscopy

SIGNIFICANCE

Fourier ptychographic microscopy (FPM) enables quantitative phase imaging with a large field-of-view and high resolution by acquiring a series of low-resolution intensity images corresponding to different spatial frequencies stitched together in the Fourier domain. However, the presence of various aberrations in an imaging system can significantly degrade the quality of reconstruction results. The imaging performance and efficiency of the existing embedded optical pupil function recovery (EPRY-FPM) aberration correction algorithm are low due to the optimization strategy.

AIM

An aberration correction method (AA-P algorithm) based on an improved phase recovery strategy is proposed to improve the reconstruction image quality.

APPROACH

This algorithm uses adaptive modulation factors, which are added while updating iterations to optimize the spectral function and optical pupil function updates of the samples, respectively. The effectiveness of the proposed algorithm is verified through simulations and experiments using an open-source biological sample dataset.

RESULTS

Experimental results show that the proposed AA-P algorithm in an optical system with hybrid aberrations, recovered complex amplitude images with clearer contours and higher phase contrast. The image reconstruction quality was improved by 82.6% when compared with the EPRY-FPM algorithm.

CONCLUSIONS

The proposed AA-P algorithm can reconstruct better results with faster convergence, and the recovered optical pupil function can better characterize the aberration of the imaging system. Thus, our method is expected to reduce the strict requirements of wavefront aberration for the current FPM.

Reduction in required volume of imaging data and image reconstruction time for adaptive-illumination Fourier ptychographic microscopy

Fourier ptychographic microscopy (FPM) is a promising super-resolution computational imaging technology. It stitches a series of low-resolution (LR) images in the Fourier domain by an iterative method. Thus, it obtains a large field of view and high-resolution quantitative phase images. Owing to its capability to perform high-spatial bandwidth product imaging, FPM is widely used in the reconstruction of conventional static samples. However, the influence of the FPM imaging mechanism limits its application in high-speed dynamic imaging. To solve this problem, an adaptive-illumination FPM scheme using regional energy estimation is proposed. Starting with several captured real LR images, the energy distribution of all LR images is estimated, and select the measurement images with large information to perform FPM reconstruction. Simulation and experimental results show that the method produces efficient imaging performance and reduces the required volume of data to more than 65% while ensuring the quality of FPM reconstruction.

[Depressive symptoms are not associated with risks of rapid renal function decline or chronic kidney disease in middle-aged and elderly with normal kidney function: a longitudinal investigation]

OBJECTIVE

To explore the association between depressive symptoms and the risks of rapid decline in renal function and chronic kidney disease (CKD) in middle-aged and elderly with normal kidney function.

METHODS

The residents aged 40- 75 years with eGFR≥60 mL·min^-1·1.73 m^-2 without proteinuria in Lanzhou region, who participated in the "REACTION" study carried out in 2011, were selected and followed up in 2014. A total of 4961 individuals with complete and qualified data from the two surveys were included in the subsequent analysis. Based on PHQ-9 questionnaire scores, the baseline population was divided into two groups with and without depressive symptoms. Cox proportional hazard analysis was used to compare the incidences of rapid renal function decline and CKD between the two groups and study the association of depressive symptoms with the risk of these renal conditions.

RESULTS

PHQ-9 questionnaire scores were not found to correlate with baseline SCr, ALB, UACR or eGFR levels among the participarts (P>0.05). After a mean follow-up time of 3.4±0.6 years, 33.9% of the participants with depressive symptoms at baseline experienced a rapid decline in renal function and 3.6% progressed to CKD. During the follow-up, the incidence of rapid decline in renal function and the risk of developing CKD were not found to correlate with depressive symptoms in these participants (P>0.05) regardless of the type of the depressive syndromes.

CONCLUSION

Depressive symptoms are not associated with the risks of rapid renal function decline or progression to CKD in middle-aged and elderly with normal kidney function.

[Correlation of baseline serum 25-hydroxyvitamin D level with the risk of type 2 diabetes mellitus: a prospective cohort study]

OBJECTIVE

To investigate the correlation of baseline serum 25(OH) D level with the risk of type 2 diabetes mellitus (T2DM) and blood glucose control in diabetic patients among the middle-aged and elderly individuals in Chengguan District of Lanzhou, Gansu Province.

OBJECTIVE

Residents aged 40 to 75 years in Lanzhou were selected from the "REACTION" study conducted in 2011 and had been followed up since 2014. A total of 5044 subjects with complete data from the two surveys were analyzed. Participants were divided into Q1, Q2, Q3, and Q4 subgroups based on quartiles of serum 25(OH)D level for comparison of the incidence of T2DM and blood glucose control.

OBJECTIVE

Baseline 25(OH)D level was not found to correlate with FPG, 2h-PG or HbA1c levels among the residents (P>0.05). The participants were followed up for a mean of 3.4±0.6 years, and compared with those in Q1 group, the participants in Q2, Q3 and Q4 groups did not show significantly lowered risk of prediabetes or diabetes regardless of glucose tolerance status. Among the patients with T2DM, the compliance rate of glycemic control after the follow-up was significantly higher than that before the follow-up (63.4% vs 60.6%), and the levels of HbA1c, FPG, and 2h-PG decreased obviously after the follow-up. But compared with Q1 group, Q2, Q3 and Q4 groups showed no significant changes in glycemic control compliance rate or levels of HbA1c, FPG and 2h-PG after the follow-up (P>0.05).

OBJECTIVE

There is no evidence that baseline 25(OH)D levels are associated with the risk of diabetes and blood glucose control in patients with T2DM.

A36 IMPACT OF DIGITAL HEALTH MONITORING IN THE MANAGEMENT OF INFLAMMATORY BOWEL DISEASE

Background

Inflammatory bowel disease (IBD) affects over 270,000 Canadians and costs the healthcare system $1.28 billion dollars annually. With advancements in technology, a shift from the traditional ‘reactive’ approach to IBD management to a ‘proactive’ approach that integrates self-management strategies using digital health monitoring platforms could greatly benefit patient care.

Aims

The purpose of this study was to investigate the effect of implementing the IBD health monitoring platform, HealthPROMISE, in clinical practice and to evaluate whether its use leads to better quality of care, improved health outcomes, and reduce resource consumption in patients with IBD.

Methods

IBD patients were recruited in gastroenterology clinics and asked to install the HealthPROMISE application onto their smartphones. Patient satisfaction, quality of care, quality of life, patient symptoms, and resource utilization metrics were collected throughout the study and sent directly to their healthcare teams. Patients with abnormal symptom/short inflammatory bowel disease questionnaire (SIBDQ) scores were flagged for their physicians to follow up with. After one-year, patient outcome metrics were compared to baseline values.

Results

Overall, out of 59 patients enrolled in the study, 32 patients (54%) logged into the application at least once during the study period. The number of IBD-related ER visits/hospitalizations in the year of use compared to the prior year demonstrated a significant decrease from 25% of patients (8/32) to 3% (1/32) (p=0.03). Patients also reported an increase in their understanding of the nature/causes of their condition after using the application (p=0.026). No significant changes were observed in the number of quality indicators met (p = 0.67) or in SIBDQ scores (p=0.48).

Conclusions

Given the significant burden of IBD, there is a need to develop effective management strategies. This study demonstrated that digital health monitoring platforms may aid in reducing the number of ER visits and hospitalizations in IBD patients. Future studies evaluating acceptability and costs with a larger sample size would help determine the feasibility and generalizability of widely implementing mobile health applications in the management of IBD.

Funding Agencies

CCC

A11 RISK PERCEPTION AND KNOWLEDGE OF COVID-19 IN PATIENTS WITH CELIAC DISEASE

Background

Celiac disease (CeD) has been associated with an increased risk of respiratory infections, however, we recently demonstrated that the odds of contracting COVID-19 in patients with CeD is similar to that of the general population. Due to this discrepancy, how patients with CeD perceive their risk may differ from their actual risk.

Aims

The aim of this study was to investigate the risk perceptions for contracting COVID-19 in patients with CeD and to determine the factors that may influence their perceptions.

Methods

We distributed a survey throughout 10 countries between March and June 2020 and collected data on demographics, diet, COVID-19 testing, and risk perceptions of COVID-19 in patients with CeD. Participants were recruited through various celiac associations, clinic visits, and social media. Risk perception was assessed by asking individuals whether they believe patients with CeD are at an increased risk of contracting COVID-19 compared to the general population. Logistic regression was used to determine the influencing factors associated with COVID-19 risk perception, such as age, sex, adherence to a gluten-free diet (GFD), and comorbidities such as cardiac/respiratory conditions and diabetes. Data was presented as adjusted odds ratios (aORs).

Results

A total of 10,737 participants with CeD completed the survey. From them, 6,019 (56.1%) patients with CeD perceived they were at a higher risk or were unsure if they were at a higher risk of contracting COVID-19 compared to the non-CeD population. A greater proportion of patients with CeD had high levels of COVID-19 risk perceptions when compared to infections in general (56.1% vs 26.7%; p<0.0001). Consequently, 28.8% reported taking extra COVID-19 precautions as a result of their CeD. Members of celiac associations had lower rates of perceiving an increased risk of COVID-19 when compared to non-members (49.5% vs 57.4%, p<0.0001). Older age (aOR: 0.9; 95% CI: 0.9 to 1, p<0.001), male sex (aOR: 0.85; 95% CI: 0.76 to 0.94, p=0.001), and strict adherence to a GFD (aOR: 0.89; 95% CI 0.82 to 0.97, p=0.007) were associated with a lower perception of COVID-19 risk. Meanwhile, the presence of comorbidities was associated with a higher perception of COVID-19 risk (aOR: 1.34; 95% CI: 1.20 to 1.51, p<0.001).

Conclusions

Overall, a large proportion of patients with CeD, particularly females, those with comorbidities, or those not adhering to a strict GFD, believed they were or were unsure if they were at a higher risk of contracting COVID-19 due to their condition. As high levels of risk perception may increase an individual’s pandemic-related stress and contribute to negative mental health consequences, healthcare providers should maintain consistent communication with the celiac community and provide them with evidence-based recommendations.

Funding Agencies

None

Dexmedetomidine attenuates myocardial ischemia/reperfusion injury through regulating lactate signaling cascade in mice

OBJECTIVE

The aim of this study was to investigate the role of dexmedetomidine (Dex) in lactate signaling cascade and myocardial ischemia/reperfusion (I/R) injury in mice.

MATERIALS AND METHODS

The left anterior descending of the coronary artery was ligatured for 30 min and then reperfused for 6 h to induce myocardial I/R injury in mice. Heart samples were collected and the levels of lactate, SOD and MDA were measured. Infarct size and myocardium were stained with triphenyltetrazolium chloride and TUNEL, respectively. In addition, the expression levels of MCT1, cytochrome c, cleaved caspase-9 and -3 were detected by Western blot.

RESULTS

The myocardial infarct size, lactate and MDA levels of the I/R group were significantly increased, whereas the SOD activity was decreased. However, Dex significantly reduced the myocardial infarct size, as well as lactate and MDA levels in contrast to the I/R group. Meanwhile, the SOD activity was remarkably increased. The expression levels of MCT1, cytochrome c, cleaved caspase-9 and -3 were significantly increased in the I/R group. In addition, Dex administration further increased the expression of MCT1, whereas decreased the expressions of cytochrome c, cleaved caspase-9 and -3 in contrast to the I/R group.

CONCLUSIONS

Dex elevated the expression of mitochondrial MCT1 and inhibited oxidative stress and the activation of mitochondria-dependent apoptosis in mice. This indicated that Dex attenuated myocardial I/R injury by regulating lactate signaling cascade.

Transmission of respiratory viruses when using public ground transport: A rapid review to inform public health recommendations during the COVID-19 pandemic

In response to the COVID-19 pandemic, numerous countries worldwide declared national states of emergency and implemented interventions to minimise the risk of transmission among the public. Evidence was needed to inform strategies for limiting COVID-19 transmission on public transport. On 20 March 2020, we searched MEDLINE, CENTRAL, Web of Science and the World Health Organization's database of 'Global research on coronavirus disease (COVID-19)' to conduct a rapid review on interventions that reduce viral transmission on public ground transport. After screening 74 records, we identified 4 eligible studies. These studies suggest an increased risk of viral transmission with public transportation use that may be reduced with improved ventilation. International and national guidelines suggest the following strategies: keep the public informed, stay at home when sick, and minimise public transport use. Where use is unavoidable, environmental control, respiratory etiquette and hand hygiene are recommended, while a risk-based approach needs to guide the use of non-medical masks.

The effects of dietary sodium butyrate supplementation on the growth performance, carcass traits and intestinal microbiota of growing-finishing pigs

AIM

This study was carried out to investigate the effects of dietary sodium butyrate supplementation on growth performance, carcass traits and intestinal of growing-finishing pigs.

METHODS AND RESULTS

Thirty pigs (27·4 ± 0·4 kg) were randomly assigned to receive one of three diets: basal diet (negative control group), basal diet + 40 ppm zinc bacitracin (positive control group) and basal diet + 0·2% sodium butyrate (sodium butyrate group), respectively. The experiment lasted for 69 days, including 3 days for diet and housing condition adaptation. On day 70, five piglets from each diet group were slaughtered for collecting blood and tissue samples. When compared to the control group, final body weight, daily body weight gain and daily feed intake of pigs in the sodium butyrate group were increased (P < 0·05) and feed intake/body weight gain ratio was decreased (P < 0·05). Carcass weight of pigs in the sodium butyrate group was higher than that of pigs in the negative and positive groups (P < 0·05); backfat thickness of pigs in the positive group was higher than that of pigs in the negative group and sodium butyrate group (P < 0·001). When compared to the negative and positive groups, pigs fed diet supplemented with sodium butyrate showed a increased relative abundance of bacteroidetes in the caecum and a decreased relative abundance of fiemicutes and proteobacteria in the caecum (P < 0·05).

CONCLUSION

The results indicated that dietary sodium butyrate supplementation increased growth performance of growing-finishing pigs and improved the carcass traits and intestinal health.

SIGNIFICANCE AND IMPACT OF THE STUDY

Antibiotic-free feed has become an inevitable worldwide trend. This study showed that dietary sodium butyrate supplementation improved the growth performance and intestinal health of growing-finishing pigs. Thus, sodium butyrate can be applied in growing-finishing pig feed as an alternative of antibiotics.

A compact Class D RF power amplifier for mobile nuclear magnetic resonance systems

A 20 MHz Class D amplifier with an output of 100 W of RF power has been developed. The compact size printed circuit board area of 50 cm² and efficiency of 73% make it suitable for mobile nuclear magnetic resonance (NMR) systems. Test results show that the rise and ring down times of the amplifier are less than 0.2 μs, and it is capable of producing constant amplitude pulses as short as 2 μs. Experiments using a Carr Purcell Meiboom Gill pulse sequence with a NMR MOUSE sensor confirm that the Class D amplifier is suitable for mobile NMR applications.

Allelic polymorphism of KIR2DL2/2DL3 in a southern Chinese population

KIR2DL2 and KIR2DL3 segregate as alleles of the same killer cell immunoglobulin-like receptor (KIR) gene locus. They have been associated with viral infectious diseases and certain cancers and their allelic information may help to better comprehend mechanisms. The allelic polymorphism of KIR2DL2/2DL3 has been shown to influence their binding specificity and affinity to the HLA-C1 ligands. The present study aims to investigate the distribution of the allelic polymorphism of KIR2DL2/2DL3 in a southern Chinese population using sequence-specific primer polymerase chain reaction (PCR-SSP) and PCR-sequence-based typing (SBT) at the entire coding sequence. Of the 306 tested individuals, 1.96% were positive for KIR2DL2 only, 78.10% for KIR2DL3 only, and 19.93% for both KIR2DL2 and 2DL3. KIR2DL3 showed a high degree of diversity in the study population with 15 alleles detected including 8 novel ones. The predominant 2DL3 allele in the study population is 2DL3*00101 (92.81%) followed by 2DL3*00201 (24.18%), 2DL3*023 (4.25%), and 2DL3*00109 (1.31%). The remaining 11 2DL3 alleles all had a frequency below 1%. Three detected 2DL2 alleles were 2DL2*00301 (18.95%), 2DL2*00101 (3.59%), and the novel 2DL2*013 (0.33%). These results provide further insight into the KIR gene diversity in Southern Chinese and may help to better understand the role played by KIR genes in associated diseases.

A novel KIR2DL3 variant allele, KIR2DL3*032, which has arisen by a missense mutation in codon 231

The novel 2DL3*032 allele differs from the closest allele KIR2DL3*0010101 by a non-synonymous mutation in exon 7.

HLA-A*11:188: a new allele identified by sequence-based typing in a Chinese blood donor

A novel allele HLA-A*11:188 differs from HLA-A*11:01:01 by a single mutation at position 439 in exon 3.

Identification of the novel KIR3DL1*01505 allele from southern Chinese Han individual

The novel KIR3DL1*01505 allele differs from the closest allele KIR3DL1*0150201 by a single silent mutation.

Identification of the novel HLA-C*03:240 allele

HLA-C*03:240 differs from HLA-C*03:42 by a single nucleotide substitution that results in a missense mutation Tyr 99 Cys (TAT to TGT).

Identification of a novel HLA-C*04 allele, HLA-C*04:162

HLA-C*04:162 differs from the closely matching allele C*04:01:01:01 by one nucleotide substitution in exon 4 at position 883 A/G.

Reveals new lung adenocarcinoma cancer genes based on gene expression

BACKGROUND

Lung adenocarcinoma (LAC) is the most common type of lung cancer, accounting for 30-35% of all cases.

AIM

In this study we aim to predict potential genes and confirm pathways which are associated with LAC.

MATERIALS AND METHODS

By using the meta-analysis method, GSE10072 and GSE 2514 datasets were merged to find potential genes and pathways which are associated with LAC.

RESULTS

Our analysis indicated identified differentially expressed genes enriched in multicellular organismal metabolic process, gland development, and urogenital system development. Further, we predicted genes including EGF-like domain might be the potential target genes for further study, such as NGX6, MUC17, and Nel. In addition, a number of genes that associated with axon guidance, focal adhesion, and complement and coagulation cascades pathway might be also involved in LAC in a direct or indirectly manner.

CONCLUSIONS

Our analysis indicated identified differentially expressed genes enriched in multicellular organismal metabolic process, gland development, and urogenital system development We anticipate numerous advances in LAC research in the coming years based on our meta-analysis.

Urinary excretion and renal production of hepatocyte growth factor in children with Henoch-Schönlein purpura

This study measured urinary excretion and renal levels of hepatocyte growth factor (HGF) in children with Henoch-Schönlein purpura (HSP), examining the relationship between HGF, proteinuria and renal pathological changes. Seventy-eight patients with HSP aged 6 - 18 years were divided into three groups, based on urinary albumin excretion rate. Urinary HGF concentration was measured by enzyme-linked immunosorbent assay. Renal biopsies were performed in 22 patients; renal levels of HGF protein were determined immunohistochemically. Compared with controls, urinary HGF was significantly increased in patients with normoalbuminuria and microalbuminuria, especially in those with microalbuminuria; no differences were observed between patients with macroalbuminuria and controls. Little or no HGF was present in normal kidney, but HGF was present in renal tissue in all HSP patients, particularly those with microalbuminuria. Urinary HGF was strongly correlated with the presence of renal HGF. These results suggest that HGF is associated with proteinuria and renal pathological changes in children with HSP. The detection of urinary HGF in children with HSP may be a non-invasive, effective, method for early diagnosis of renal injury.

Upregulation of endothelial and inducible nitric oxide synthase expression by reactive oxygen species

BACKGROUND

The effect of reactive oxygen species (ROS) on nitric oxide synthase (NOS) expression remains uncertain. This study explored the effect of increased ROS activity on NOS expression in vitro in human coronary artery endothelial cells (HCAECs) grown in culture and in intact animals.

METHODS

Endothelial NOS (eNOS) expression and nuclear factor kappaB (NFkappaB) activation were determined in HCAECs grown in culture and exposed to oxidative stress with xanthine-xanthine oxidase (X-XO) generated superoxide, H(2)O(2), or glutathione depletion with buthionine sulfoximine (BSO) for 24 h. In parallel experiments, cells were treated with a nitric oxide (NO) scavenger (hemoglobin), and with an NO donor S-nitroso-N-acetyl penicillamine (SNAP)]. In addition, eNOS and inducible NOS (iNOS) expressions were determined in rats treated with either BSO or vehicle for 48 h.

RESULTS

Increases in ROS activity, achieved by exogenous superoxide and H(2)O(2) or by glutathione depletion, upregulated the expression of eNOS at both transcriptional and translational levels in HCAECs. Similar effects were seen with the non-radical NO scavenger, hemoglobin. The upregulatory action of hemoglobin on eNOS messenger RNA (mRNA) and protein expressions was overcome by the NO donor, SNAP, thereby suggesting that there is a negative feedback regulation of eNOS by NO. Nuclear translocation of NFkappaB (p65) was noted within 5 min of exposure to H(2)O(2) and at least 15 min after exposure to superoxide or BSO. Induction of oxidative stress by glutathione depletion led to upregulation of renal and aorta eNOS and iNOS in live animals.

CONCLUSIONS

An increase in ROS activity upregulates NOS expression in vitro in HCAECs grown in culture, and also in vivo in animals. This effect appears to be, in part, mediated by limiting the availability of NO, thereby exerting a negative feedback influence on NOS expression through activation of NFkappaB.

Dihydropyrimidine dehydrogenase activity correlates with fluorouracil sensitivity in breast cancer

The fluoropyrimidine drug fluorouracil (FU) is one of the most frequently prescribed chemotherapeutic drugs for the curative and palliative treatment of various cancer patients. The identification of biological factors associated with tumors either responsiveness or resistance to FU chemotherapy, including FU, is increasingly being recognized as an important field of clinical cancer research.

AIM

to analyze the relationship between intra-tumoral dihydropyrimidine dehydrogenase (DPD) level and FU chemosensitivity, as DPD is the initial and rate-limiting enzyme in the catabolism of FU.

MATERIALS AND METHODS

The histoculture drug response assay (HDRA) was performed for 54 patients. DPD expression was examined in 81 tumor samples from breast cancer patients received two cycles of FU-based primary chemotherapy before operation.

RESULTS

We found that intra-tumoral DPD enzyme activity was inversely correlated with FU cytotoxicity. We also revealed that low DPD expression was correlated with clinical response to FU-based primary chemotherapy.

CONCLUSIONS

Our study indicated that DPD is a promising molecular maker for identifying tumor cells sensitivity in breast cancer patients receiving FU-based chemotherapy.

The importance of company: Na+ and Cl- influence substrate interaction with SLC6 transporters and other proteins

SLC6 transporters, which include transporters for gamma-aminobutyric acid (GABA), norepinephrine, dopamine, serotonin, glycine, taurine, L-proline, creatine, betaine, and neutral cationic amino acids, require Na+ and Cl- for their function, and this review covers the interaction between transporters of this family with Na+ and Cl- from a structure-function standpoint. Because detailed structure-function information regarding ion interactions with SLC6 transporters is limited, we cover other proteins cotransporting Na+ or Cl- with substrate (SLClA2, PutP, SLC5A1, melB), or ion binding to proteins in general (rhodanese, ATPase, LacY, thermolysine, angiotensin-converting enzyme, halorhodopsin, CFTR). Residues can be involved in directly binding Na+ or Cl-, in coupling ion binding to conformational changes in transporter, in coupling Na+ or Cl- movement to transport, or in conferring ion selectivity. Coordination of ions can involve a number of residues, and portions of the substrate and coupling ion binding sites can be distal in space in the tertiary structure of the transporter, with other portions that are close in space thought to be crucial for the coupling process. The reactivity with methanethiosulfonate reagents of cysteines placed in strategic positions in the transporter provides a readout for conformational changes upon ion or substrate binding. More work is needed to establish the relationships between ion interactions and oligomerization of SLC6 transporters.

Immunocapture UPPCR combined with DGGE for rapid detection of Shigella species

AIMS

To develop an immunocapture universal primer PCR (iUPPCR) combined with denaturing gradient gel electrophoresis (DGGE) and evaluate it as a method permitting rapid detection of Shigella species and their serotypes.

METHODS AND RESULTS

This method amplifying the conserved regions of bacterial 16S rRNA genes of different species or serotypes of Shigella dysentery bacilli captured and enriched by polyvalent antibodies can detect and distinguish causative pathogens rapidly. Four serotypes from three Shigella species including Shigella dysenteriae serotype 1, Shigella boydii serotype 1, Shigella flexneri serotypes 1a and 3a were examined.

CONCLUSION

Our approach could be adopted for not only axenic bacterial population but also mixed communities and achieve rapid detection of various bacteria from the same genus or species in one sample.

SIGNIFICANCE AND IMPACT OF THE STUDY

The iUPPCR-DGGE method was shown to be more convenient than serotype-specific-antibody-based method of iUPPCR for Shigella species detection and it could be also applied to the quick detection for other kinds of pathogens with many serotypes.

Thymidylate synthase predicts for clinical outcome in invasive breast cancer

Thymidylate synthase (TS) is a major target of 5-fluorouracil (5-FU) and dihydropyrimidine dehydrogenase (DPD) is a rate-limiting enzyme in the degradation of 5-FU. Whether TS or DPD could be used as valuable parameters for 5-FU sensitivity in clinical patients are largely unknown. We analyzed TS and DPD expression in breast carcinomas to evaluate the clinicopathological significance of these enzymes in patients with invasive breast cancer receiving 5-FU-based chemotherapy. A total of 197 patients with invasive ductal carcinoma were included in our study. Both the TS and DPD expression were analyzed using immunohistochemical method for all the surgical samples. Sixty-three out of 197 (31.97%) patients are positive for TS expression, and 77 out of 197 (39.09%) patients are positive for DPD expression. TS expression was not correlated with DPD expression. Patients with TS-positivity had aggressive phenotype including large tumor size, low differentiation and nodal metastasis. DPD expression is not related with phenotype or prognosis. Multivariate analysis demonstrated that TS expression was an independent prognostic factor for both disease-free and overall survival. The current study demonstrated that TS but not DPD expression was associated with both progression and prognosis in breast cancer receiving 5-FU-based chemotherapy. TS expression in the primary tumor might be useful as a predictive parameter for the efficacy of 5-FU-based chemotherapy for breast cancer.

Chinese medicinal herbs for acute bronchitis

BACKGROUND

Acute bronchitis is one of the most common diagnoses made by primary-care physicians. It is traditionally treated with antibiotics, (although the evidence for their effectiveness is weak and modest at best), and other even less effective treatments. Chinese medicinal herbs have been also used as treatment.

OBJECTIVES

This review aims to summarise the existing evidence on the comparative effectiveness and safety of Chinese medicinal herbs for treating uncomplicated acute bronchitis.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 1, 2005), which includes the Cochrane Acute Respiratory Infections Group's specialised register; The Chinese Cochrane Centre's Controlled Trials Register (up to December 2004); MEDLINE (1966 to March Week 1, 2005); EMBASE (1988 to December 2004); and the Chinese Biomedical Database (CBM) (1980 to December 2004).

SELECTION CRITERIA

Randomised controlled trials comparing Chinese medicinal herbs with placebo, antibiotics or other Western medicines for the treatment of uncomplicated acute bronchitis.

DATA COLLECTION AND ANALYSIS

At least two authors extracted data and assessed trial quality.

MAIN RESULTS

Four trials reported the time to improvement of cough, fever, and rales associated with bronchitis and showed that patients treated with Chinese herbs had a shorter duration of signs and symptoms. Two trials reported the proportion of patients with improved signs and symptoms at follow up and showed that Chinese herbs were beneficial in terms of relief of signs and symptoms. Thirteen trials analysed the data on physician global assessment of improvement at follow up. Nine of thirteen trials showed that Chinese herbs were superior to routine treatment and the other four trials showed a similar effect to routine treatment. In general, Chinese herbs appeared beneficial. Only one trial reported on adverse effects during treatment.

AUTHORS' CONCLUSIONS

There is insufficient quality data to recommend the routine use of Chinese herbs for acute bronchitis. The benefit found in this systematic review could be due to publication bias and study-design limitations of the individual studies. In addition, the safety of Chinese herbs is unknown due to the lack of toxicological evidence on these Chinese herbs, though adverse events are rarely reported. Chinese herbs should be used carefully.

[Adverse drug reaction and rational use of levofloxacin: a prospective study]

OBJECTIVE

To study the rate of adverse drug reaction(ADR) and the rational use of levofloxacin among in-patients.

METHOD

All in-patients treated with levofloxacin were prospectively observed in 7 hospitals of Beijing.

RESULTS

One hundred and five ADR cases were found in 2,661 patients injected with levofloxacin. The ADR rate was 3.9% while 4.8% of them were classified as severe cases. All severe ADR cases had a nature of double infections. The ADR occurrence was related to older age, irrational drug use, combined medicine and allergic history. The rate of levofloxacin irrational use was 19.9%, especially in the elderly population, due to too long or too short course of treatments.

CONCLUSION

Levofloxacin is viewed as a safe injection in clinical practice, however, combined medicine and elderly patients should be paid more attention when on administration of this medication. The irrational use of levofloxacin was recognized as one of the main reasons causing the increase of ADR.

Effect of pH and soybean cultivars on the quantitative analyses of soybean rhizobia populations

Quantitative analyses of fast- and slow-growing soybean rhizobia populations in soils of four different provinces of China (Hubei, Shan Dong, Henan, and Xinjiang) have been carried out using the most probable number technique (MPN). All soils contained fast- (FSR) and slow-growing (SSR) soybean rhizobia. Asiatic and American soybean cultivars grown at acid, neutral and alkaline pH were used as trapping hosts for FSR and SSR strains. The estimated total indigenous soybean-rhizobia populations of the Xinjiang and Shan Dong soil samples greatly varied with the different soybean cultivars used. The soybean cultivar and the pH at which plants were grown also showed clear effects on the FSR/SSR rations isolated from nodules. Results of competition experiments between FSR and SSR strains supported the importance of the soybean cultivar and the pH on the outcome of competition for nodulation between FSR and SSR strains. In general, nodule occupancy by FSRs significantly increased at alkaline pH. Bacterial isolates from soybean cultivar Jing Dou 19 inoculated with Xinjiang soil nodulate cultivars Heinong 33 and Williams very poorly. Plasmid and lipopolysaccharide (LPS) profiles and PCR-RAPD analyses showed that cultivar Jing Dou 19 had trapped a diversity of FSR strains. Most of the isolates from soybean cultivar Heinong 33 inoculated with Xinjiang soil were able to nodulate Heinong 33 and Williams showed very similar, or identical, plasmid, LPS and PCR-RAPD profiles. All the strains isolated from Xinjiang province, regardless of the soybean cultivar used for trapping, showed similar nodulation factor (LCO) profiles as judged by thin layer chromatographic analyses. These results indicate that the existence of soybean rhizobia sub-populations showing marked cultivar specificity, can affect the estimation of total soybean rhizobia populations indigenous to the soil, and can also affect the diversity of soybean rhizobial strains isolated from soybean nodules.

Adapalene gel 0.1%: effective and well tolerated in the topical treatment of acne vulgaris in Chinese patients

Acne vulgaris is a common dermatologic disease in Asian populations, as well as in Caucasians. Our objective was to evaluate the safety and efficacy of adapalene gel 0.1% in comparison with tretinoin gel 0.025% in Chinese patients with acne vulgaris. We used an 8-week, multicenter, randomized, controlled, investigator-masked, parallel group design study of adapalene gel 0.1% and tretinoin gel 0.025% in 150 Chinese patients with mild-to-moderate acne vulgaris. Our results showed that adapalene gel 0.1% had efficacy equivalent to tretinoin gel 0.025% against acne lesions in Chinese patients, with a more acceptable tolerability profile.

[The relationship between chemotherapy and multidrug resistance of lung cancer]

BACKGROUND

To investigate the relationship between multidrug resistance(MDR) and chemotherapy and the possibility of P-gp as a clinical prognostic indicator.

METHODS

P-gp, MDR1 gene product, was detected in 66 cases of relapsed lung cancer patients after chemotherapy and 131 lung cancer patients with no prior chemotherapy by immunohistochemistry.

RESULTS

The expressive level of P-gp in relapsed group after chemotherapy was much higher than that of non-chemotherapy group (P<0.05). A significant difference of P-gp expression existed between before and after chemotherapy for squamous cell carcinoma and SCLC (P<0.05), but not for adenocarcinoma. In non-chemotherapy group, lung cancer tissues with different histological types had different P-gp positive rates, which were adenocarcinoma, squamous cell carcinoma and SCLC in sequence from high to low (P<0.05). In relapsed group after chemotherapy, there was no significant difference among the three types of lung cancer (P>0.05). P-gp positive group had a significantly lower 3-year survival rate than negative group (P<0.05).

CONCLUSIONS

Chemotherapy may increase the incident rate of MDR in lung cancer. Adenocarcinoma is mainly primary MDR while SCLC and squamous cell carcinoma are mainly secondary to chemotherapy. P-gp expressive level can be used as a common clinical indicator for prognosis and chemotherapy in the patients with lung cancer.

[Epidemiological survey and analysis on bronchial asthma in Guangdong Province]

OBJECTIVE

To survey asthma prevalence and risk factors of asthma in Guangdong and then to provide a basic consideration for research and preventive and therapeutic poliaes for control of asthma.

METHODS

Using uniform scheme, procedures and questionnaire, performing stratified-cluster-disproportional-random-sampling survey for the population in six areas: Santou, Shenzhen, Zhanjiang, Shaoguan, Fushan and Guangzhou; quantitative sample the prevalence rate quantitated is 1.5% (P = 0.015, q = 0.985), a sampling number stratified = 178 x 0.985/0.015 = 11,689, if the whole province were stratified into six areas, a total of 70,134 persons were supposed to be investigated, in this survey 71,867 subjects were actually examined; all the original data were inputted into soft discs in the same form of data base structure variable definition table, and then were statistically analyzed with spas 8.0 for windows on P III/450 computer, all the prevalence rates were compared by chi 2 test.

RESULTS

In this survey 676 asthmatics were found, the overall prevalence rate was 0.94%, the ratio of male to female was 1.38:1; the rate of adults was 0.99% and that of children was 0.73%, three groups with higher prevalence were children of preschool period (age < 7 years, 1.03%), young period (age 18-25 years, 1.00%) and senile period (age 66-75 years, 2.99%); the rate of city (Fushan, 1.38%) was higher than that of rural area (Zhanjiang, 0.47%); the rate of old district (1.70%) was higher than that of the new district (0.23%) in Guangzhou and the rate of historic city (Fushan, 1.38%) was higher than that of the newly developed city (Shenzhen, 0.64%); risk factors found among 676 asthmatics, persons keeping pets (cat, dog, fowl, bird) in home were reported by 46.0% (311/676), those keeping cat was 43.1% (134/311), particularly those keeping cat and both cat and dog accounted for 61.7% (192/311). Persons often exposed to side-stream smoke were reported by 54.7%. Asthmatics with allergic rhinititis were reported by 38.2%. The attack contributed to change temperature or to inhale cold air was 41.6% respectively.

CONCLUSION

This survey had basically reflected the distribution, Frequency and intensity of asthma, the overall prevalence rate was 0.94% from which it would be estimated that there could be 670,000 asthmatics in Guangdong; the relative data will provide basis for research work concerned and mass prevention and treatment of asthma.

[Linkage analysis of chromosome 5 and asthma in a Chinese population]

OBJECTIVE

To investigate the linkage between asthma and 5q31-33 in a Chinese population.

METHODS

The linkage between microsatellite markers in 5q and asthma and allergy was tested by lod score analysis.

RESULTS

The linkage between asthma and 5q31-33 was not confirmed.

CONCLUSION

The genes at 5q31-33 are not likely to contribute to inheritance of asthma in this Chinese population.

[The study on the culture, freezing preservation and resuscitation of human trabecular cells in vitro]

PURPOSE

To establish the culture of human trabecular cells in vitro and study the freezing preservation and resuscitation.

METHODS

The trabecular specimens from human eyes were cultured in vitro and passaged 3 times, then the cultured cells were frozen and preserved. The frozen cells were resuscitated after one week, two weeks, one month and two months.

RESULTS

Cultured human trabecular cells were obtained. The frozen cells were resuscitated successfully. All of the resuscitated rates were more than 90%.

CONCLUSION

The human trabecular cells were cultured in vitro successfully, they can also be frozen and resuscitated, which will be helpful to the establishment of cDNA library and the screening of associated glaucomatous genes.