Inflammatory biomarkers may be associated with poor outcomes after mechanical thrombectomy.

BACKGROUND: Mechanical thrombectomy (MT) has become the mainstay of treatment for acute ischemic stroke (AIS) recently. This case-control study aimed to identify the pivotal role of inflammation in the prognosis of AIS patients after MT. METHODS: Altogether, 70 AIS patients who underwent MT were retrospectively recruited for this study. Receiver operating characteristic analysis was performed to demonstrate the sensitivity and specificity of the inflammatory variables for predicting prognosis. A meta-analysis was performed to pool the published results together. Stata software was used for analysis. RESULTS: There was no differences in pre-MT inflammatory biomarkers between patients who survived and those who died, as well as patients with modified Rankin Scale (mRS) 0-2 and mRS ≥ 3. In contrast, post-MT C-reactive protein (CRP) levels might be a potential parameter to predict death after thrombectomy [area under the curve (AUC), 95%confidence interval (CI), 0.737, 0.587-0.887; p = 0.005; optimal cutoff value = 4.565]. Moreover, post-MT monocyte count might be an appropriate parameter to predict poor long-term prognosis after thrombectomy (AUC, 95%CI, 0.704, 0.575-0.833; p = 0.017; optimal cutoff value = 0.345). A meta-analysis revealed that the pre-MT inflammatory indices, including white blood cell count (weighted mean difference, 95%CI, 1.32, 1.01-1.63), neutrophil count (1.23, 0.95-1.51), monocyte count (0.05, 0.02-0.09), neuthrophil-to-lymphocyte ratio (2.42, 1.98-2.87) and platelet-to-lymphocyte ratio (24.65, 7.99-41.32), were higher in patients with 3-month mRS ≥ 3, and the lymphocyte count (-0.31,-0.43 to -0.18) was lower in this cohort. CONCLUSIONS: Inflammatory indices were significantly associated with the prognosis of patients undergoing MT, especially post-MT CRP and monocyte count, which can predict long-term outcomes.

Development of an all-in-one real-time PCR assay for simultaneous detection of spotted fever group rickettsiae, severe fever with thrombocytopenia syndrome virus and hantaan virus prevalent in central China.

Central China has been reported to be one of the most important endemic areas of zoonotic infection by spotted fever group rickettsiae (SFGR), severe fever with thrombocytopenia syndrome virus (SFTSV) and hantaan virus (HTNV). Due to similar clinical symptoms, it is challenging to make a definite diagnosis rapidly and accurately in the absence of microbiological tests. In the present study, an all-in-one real-time PCR assay was developed for the simultaneous detection of nucleic acids from SFGR, SFTSV and HTNV. Three linear standard curves for determining SFGR-ompA, SFTSV-L and HTNV-L were obtained within the range of 101-106 copies/µL, with the PCR amplification efficiencies ranging from 93.46% to 96.88% and the regression coefficients R2 of >0.99. The detection limit was 1.108 copies/µL for SFGR-ompA, 1.075 copies/µL for SFTSV-L and 1.006 copies/µL for HTNV-L, respectively. Both the within-run and within-laboratory coefficients of variation on the cycle threshold (Ct) values were within the range of 0.53%-2.15%. It was also found there was no statistical difference in the Ct values between single template and multiple templates (PSFGR-ompA = 0.186, PSFTSV-L = 0.612, PHTNV-L = 0.298). The sensitivity, specificity, positive and negative predictive value were all 100% for determining SFGR-ompA and SFTSV-L, 97%, 100%, 100% and 99.6% for HTNV-L, respectively. Therefore, the all-in-one real-time PCR assay appears to be a reliable, sensitive, rapid, high-throughput and low cost-effective method to diagnose the zoonotic infection by SFGR, SFTSV and HTNV.

An all-in-one enzymatic DNA network based on catalytic hairpin assembly for label-free and highly sensitive detection of APE1.

Apurinic/apyrimidinic endonuclease 1 (APE1), identified as a prospective cancer biomarker, plays a vital role in the occurrence and progression of cancer cell lines and impacts on genome stability. However, conventional approaches typically rely on the interactions between the antigen and antibody, limiting their utility for qualitative assessments of APE1 expression. Herein, an all-in-one enzymatic DNA network (EDN) assay with catalytic hairpin assembly for label-free and ultrasensitive detection of APE1 has been developed. In this work, the blocking strand can inhibit the initiator by obstructing the complementary region, preventing the hairpin from hybridizing in the absence of APE1 targets. While the presence of targets can activate the unlocking of the initiator, which can trigger the catalytic hairpin reaction, and increase the fluorescent signal. Under optimal conditions, the developed sensing method can detect the target APE1 down to 4.78 × 10-6 U mL-1 with a wide linear range from 5 × 10-6 U mL-1 to 30 U mL-1. This strategy has also been successfully applied to the analysis of complicated biological samples compared to ELISA, demonstrating its potential applications in biochemical and molecular biology research as well as clinical diagnostics. Overall, benefiting from the high amplification efficiency, this strategy has successfully and simply detected low-abundance APE1 without additional enzyme isolation steps, presenting great potential for clinical detection applications.

[Cross-Sectional Study of Nutritional Status and Dietary Nutrient Intake in Children with Duchenne Muscular Dystrophy (DMD) in China].

Objective: To investigate the dietary nutrient intake and the nutritional status of children with Duchenne muscular dystrophy (DMD), and to explore the correlation between them, so as to provide theoretical basis for the formulation of proper nutritional treatment for children with DMD. Methods: A total of 223 children aged 2 to 14 years who came to West China Second University Hospital, Sichuan University from July 2017 to April 2021, and who were diagnosed with DMD by genetic testing were enrolled as the subjects of the study. Dietary assessment was conducted with a 3-day 24-hour dietary recall, and serum vitamin D level was measured by chemiluminescence method. Results: Only 33.2% of the children with DMD were found to be of normal nutritional status. The incidences of stunted growth, underweight, overweight and obesity were 13.5%, 14.4%, 14.3% and 8.1%, respectively. Among the children with DMD, those with serum vitamin D deficiency and insufficiency accounted for 9.0% and 89.7%, respectively. According to the dietary recall of the children with MDM, the daily energy ratio of carbohydrate, protein and fat were (47.40±6.64)%, (14.46±2.22)%, and (38.17±5.30)%, respectively. The daily intake of dietary calcium and vitamin D were (433.32±164.39) mg per day and (155.73±89.30) IU per day, respectively. The ratio of daily protein intake to the estimated average requirement for protein ( P=0.003) and ratio of daily energy intake to the estimated energy requirement ( P=0.007) were lower in children with stunted growth than those of DMD children of normal nutritional status. Conclusion: The dietary structure of children with DMD is obviously not suited to their condition and nutritional deficiency coexists with overnutrition among them. Further research needs to be done for developing appropriate nutritional guidance programs and standardized nutritional management measures for children with DMD.

An ultrasensitive biosensing platform for FEN1 activity detection based on target-induced primer extension to trigger the collateral cleavage of CRISPR/Cas12a.

Flap endonuclease 1 (FEN1), a structure-selective endonuclease essential for DNA replication and repair, has been considered as a new promising marker for early cancer diagnosis. However, reliable, sensitive and convenient biosensors for FEN1 detection are still technically challenging. Herein, a fluorometric biosensor based on target-induced primer extension to initiate the collateral cleavage of CRISPR/Cas12a has been established for ultrasensitive and specific detection of FEN1 activity. Using branched DNA to probe FEN1 activity, the cleaved 5' flap initiated DNA polymerase-mediated primer extension to produce plenty of DNA duplexes containing protospacer adjacent motif (PAM) which act as activators to initiate the collateral cleavage activity of Cas12a protein, producing an significantly amplified fluorescence response for ultrasensitive determination of FEN1 activity. The developed biosensing platform displays excellent analytical performance, with a limit of detection (LOD) down to 8.9 × 10-5 U µL-1, and a wide linear range from 1.0 × 10-4 to 5.0 × 10-1 U µL-1. Moreover, the proposed strategy was successfully used for FEN1 detection in serums and cell lysates and suggests potential clinical applications, which may provide a reliable approach for FEN1 that will allow effective diagnosis in the early stages of related cancer.

A simple and smart AND-gate DNA nanoprobe for correlated enzymes tracking and cell-selective imaging.

Accurate cancer diagnosis and effective drug therapy entail sensitive and dynamic monitoring of intracellular key enzymes, since their expression level is closely related to disease progression. Simultaneous monitoring of correlated enzymes is promising to help unveiling mystery of cytobiological events during tumor progression and drug response, while is challenged by lacking of a robust and simple simultaneous detection strategy. In order to construct a simple and smart strategy which is complex design-avoided and doesn't need other auxiliary enzyme, here we develop an AND-gate strategy for simultaneously monitoring correlated enzymes which both are upregulated in cancer cells (telomerase and apurinic/apyrimidinic endonuclease 1). An innovative AND-gate DNA nanoprobe has been designed to avoid mutual interference and background noise, guaranteeing an enhanced fluorescent signal output upon catalyzation of dual enzymes. This AND-gate strategy achieves sensitive detection of two enzymes in an individual manner in test tube, through which the diagnostic potential of bladder cancer has been validated by telomerase detection in clinical urine sample. The AND-gate strategy enables specific intracellular imaging of dual enzymes in different cancer cell lines. Importantly, in contrast to traditional single-targeting strategies, AND-gate imaging of dual enzymes significantly improves cancer cell selectivity. Moreover, this strategy dynamically monitors enzymatic activity changes during chemoresistance induced by chemotherapeutic treatment. This simple and smart strategy has foreseeable prospect in the fields of disease diagnosis, drug prognosis evaluation, and precise fluorescence-guided surgery.

Integrating CRISPR-Cas12a with a crRNA-Mediated Catalytic Network for the Development of a Modular and Sensitive Aptasensor.

Clustered regularly interspaced short palindromic repeats (CRISPR)-Cas12a, which exhibits excellent target DNA-activated trans-cleavage activity under the guidance of a programmable CRISPR RNA (crRNA), has shown great promise in next-generation biosensing technology. However, current CRISPR-Cas12a-based biosensors usually improve sensitivity by the initial nucleic acid amplification, while the distinct programmability and predictability of the crRNA-guided target binding process has not been fully exploited. Herein, we, for the first time, propose a modular and sensitive CRISPR-Cas12a fluorometric aptasensor by integrating an enzyme-free and robust crRNA-mediated catalytic nucleic acid network, namely, Cas12a-CMCAN, in which crRNA acts as an initiator to actuate cascade toehold-mediated strand displacement reactions (TM-SDRs). As a proof of concept, adenosine triphosphate (ATP) was selected as a model target. Owing to the multiturnover of CRISPR-Cas12a trans-cleavage and the inherent recycling amplification network, this method achieved a limit of detection value of 0.16 µM (20-fold lower than direct Cas12a-based ATP detection) with a linear range from 0.30 to 175 µM. In addition, Cas12a-CMCAN can be successfully employed to detect ATP levels in diluted human serum samples. Considering the simplicity, sensitivity, and easy to tune many targets by changing aptamer sequences, the Cas12a-CMCAN sensing method is expected to offer a heuristic idea for the development of CRISPR-Cas12a-based biosensors and unlock its potential for general and convenient molecule diagnostics.

Femtomolar and locus-specific detection of N6-methyladenine in DNA by integrating double-hindered replication and nucleic acid-functionalized MB@Zr-MOF.

In this study, a novel electrochemical biosensor was constructed for ultrasensitive and locus-specific detection of N6-Methyladenine (m6A) in DNA using double-hindered replication and nucleic acid-coated methylene blue (MB)@Zr-MOF. Based on the combination of m6A-impeded replication and AgI-mediated mismatch replication, this mode could effectively stop the extension of the strand once DNA polymerase encountered m6A site, which specifically distinguish the m6A site from natural A site in DNA. Also, Zr-MOF with high porosity and negative surface potential features was carefully chose to load cationic MB, resulting a stable and robust MB@Zr-MOF electrochemical tag. As a result, the developed biosensor exhibited a wide linear range from 1 fM to 1 nM with detection limit down to 0.89 fM. Profiting from the high sensitivity and selectivity, the biosensing strategy revealed good applicability, which had been demonstrated by quantitating m6A DNA at specific site in biological matrix. Thus, the biosensor provides a promising platform for locus-specific m6A DNA analysis.

A Cascade Signal Amplification Based on Dynamic DNA Nanodevices and CRISPR/Cas12a Trans-cleavage for Highly Sensitive MicroRNA Sensing.

The variations of microRNA (miRNA) expression can be valuable biomarkers in disease diagnosis and prognosis. However, current miRNA detection techniques mainly rely on reverse transcription and template replication, which suffer from slowness, contamination risk, and sample loss. To address these limitations, here we introduce a cascade toehold-mediated strand displacement reaction (CTSDR) and CRISPR/Cas12a trans-cleavage for highly sensitive fluorescent miRNA sensing, namely CTSDR-Cas12a. In this work, the target miRNA hybridizes with the terminal toehold site of a rationally designed probe and subsequently initiates dynamic CTSDR, leading to enzyme-free target recycling and the production of multiple programmable DNA duplexes. The obtained DNA duplex acts as an activator to trigger Cas12a trans-cleavage, generating significantly amplified fluorescence readout for highly sensitive detection of the miRNA target. Under the optimal conditions, the developed sensing method can detect target miRNA down to 70.28 fM with a wide linear range from 100 fM to 100 pM. In particular, by designing a set of probes and crRNAs, we demonstrate its broad applicability for the detection of six kinds of miRNAs with high sequence specificity. Furthermore, the method can be satisfactorily applied to monitor miR-21 in total RNA extracted from cells and clinical serum samples. Considering the high sensitivity, specificity, universality, and ease of handling, this strategy provides a great potential platform for the detection of miRNA biomarkers in molecular diagnostic practice.

A highly sensitive electrochemiluminescence immunosensor for h-FABP determination based on self-enhanced luminophore coupled with ultrathin 2D nickel metal-organic framework nanosheets.

In this work, a novel ECL immunosensor based on self-enhanced luminophore and ultrathin 2D nickel MOF nanosheets was fabricated for sensitive and specific detection of h-FABP. Initially, the porous ultrathin Ni-TCPP (Fe) nanosheets with high specific surface area and plentiful active sites were newly synthesized, which could enhance ECL signal of luminol by the superior peroxidase mimics activity towards H2O2 decomposition. Then, PEI and luminol were simultaneously immobilized on Ni-TCPP (Fe) nanosheets to construct self-enhanced solid state luminophore (Ni-TCPP (Fe)-PEI-Lum), possessing desirable stability and high ECL efficiency. Furthermore, poly (indole-5-carboxylic acid) (PICA) worked as substrate with outstanding conductivity and abundant binding sites to improve sensitivity. Under optimal conditions, the designed ECL immunosensor exhibited a wide dynamic range from 100 fg mL-1 to 100 ng mL-1 and a low detection limit of 44.5 fg mL-1. In addition, the ECL immunosensor behaved excellent specificity and was successfully applied to detect target h-FABP protein in complex physiological matrix. Therefore, this work may provide an alternative method for biomarker detection in clinical diagnosis and expand the application potential of 2D MOF nanosheets in ECL technique.

Correction: Bifunctional organic sponge photocatalyst for efficient cross-dehydrogenative coupling of tertiary amines to ketones.

Correction for 'Bifunctional organic sponge photocatalyst for efficient cross-dehydrogenative coupling of tertiary amines to ketones' by Teng Zhang et al., Chem. Commun., 2017, 53, 12536-12539.

Directed Aromatic C-H Activation/Acetoxylation Catalyzed by Pd Nanoparticles Supported on Graphene Oxide.

The first solid-supported directed aromatic C-H activation/acetoxylation has been successfully developed by using palladium nanoparticles supported on graphene oxide (PdNPs/GO) as a catalyst. The practicability of this method is demonstrated by simple preparation of catalyst, high catalytic efficiency, wide functional group tolerance, and easy scale up of the reaction. A hot filtration test and Hg(0) poisoning test indicate the heterogeneous nature of the catalytic active species.

Bifunctional organic sponge photocatalyst for efficient cross-dehydrogenative coupling of tertiary amines to ketones.

A novel bifunctional organic sponge photocatalyst can enable the efficient coupling of tertiary amines with ketones in water. The asymmetric transformation can be also achieved by using this sponge photocatalyst.

Strong multiphoton absorption properties of one styrylpyridinium salt in a highly polar solvent.

Multiphoton absorption (MPA) effects have become useful for real applications as well as conceptual predictions. However, most of organic molecules exhibit small Stokes shift and reduced MPA in the highly polar solvents, which may seriously hinder their related applications. In this work, one styrylpyridinium salt has been synthesized, which exhibits outstanding properties such as bright red fluorescence at the wavelength of 626 nm in a highly polar solvent (DMSO). Importantly, it is noted that the material also exhibits strong two- and three-photon absorption action cross-section (δ2PA = 597 GM and δ3PA = 18 × 10-80 cm6∙s2∙photon-2, respectively), which can be excited in near-infrared (NIR) window I (650-900 nm) and NIR window II (1000-1450 nm). Meanwhile, two-photon in vitro bioimaging and MPA induced optical limiting behavior have been successfully demonstrated based on the chromophore.

Cerebralcare Granule® attenuates cognitive impairment in rats continuously overexpressing microRNA-30e.

Previous studies have demonstrated that dysregulation of micro (mi)RNAs is associated with the etiology of various neuropsychiatric disorders, including depression and schizophrenia. Cerebralcare Granule® (CG) is a Chinese herbal medicine, which has been reported to have an ameliorative effect on brain injury by attenuating blood­brain barrier disruption and improving hippocampal neural function. The present study aimed to evaluate the cognitive behavior of rats continuously overexpressing miRNA­30e (lenti­miRNA­30e), prior to and following the administration of CG. In addition, the mechanisms underlying the ameliorative effects of CG were investigated. The cognitive ability of the rats was assessed using an open­field test and a Morris water maze spatial reference/working memory test. A terminal deoxynucleotidyl transferase dUTP nick end labeling assay was used to detect neuronal apoptosis in the dentate gyrus of the hippocampus. Immunohistochemical analysis and western blotting were conducted to detect the expression levels of B­cell lymphoma 2 (BCL­2) and ubiquitin­conjugating enzyme 9 (UBC9), in order to examine neuronal apoptosis. The lenti­miRNA­30e rats exhibited increased signs of anxiety, depression, hyperactivity and schizophrenia, which resulted in a severe impairment in cognitive ability. Furthermore, in the dentate gyrus of these rats, the expression levels of BCL­2 and UBC9 were reduced and apoptosis was increased. The administration of CG alleviated cognitive impairment, enhanced the expression levels of BCL­2 and UBC9, and reduced apoptosis in the dentate gyrus in the lenti­miRNA­30e rats. No significant differences were detected in behavioral indicators between the lenti­miRNA­30e rats treated with CG and the normal controls. These findings suggested that CG exerts a potent therapeutic effect, conferred by its ability to enhance the expression levels of BCL­2 and UBC9, which inhibits the apoptotic process in neuronal cells. Therefore, CG may be considered a potential therapeutic strategy for the treatment of cognitive impairment in mental disorders.

Ecological restoration and recovery in the wind-blown sand hazard areas of northern China: relationship between soil water and carrying capacity for vegetation in the Tengger Desert.

The main prevention and control area for wind-blown sand hazards in northern China is about 320000 km(2) in size and includes sandlands to the east of the Helan Mountain and sandy deserts and desert-steppe transitional regions to the west of the Helan Mountain. Vegetation recovery and restoration is an important and effective approach for constraining wind-blown sand hazards in these areas. After more than 50 years of long-term ecological studies in the Shapotou region of the Tengger Desert, we found that revegetation changed the hydrological processes of the original sand dune system through the utilization and space-time redistribution of soil water. The spatiotemporal dynamics of soil water was significantly related to the dynamics of the replanted vegetation for a given regional precipitation condition. The long-term changes in hydrological processes in desert areas also drive replanted vegetation succession. The soil water carrying capacity of vegetation and the model for sand fixation by revegetation in aeolian desert areas where precipitation levels are less than 200 mm are also discussed.

Influence of basic fibroblast growth factor on the growth of HeLa cells and the expression of angiogenin.

Basic fibroblast growth factor (bFGF) is closely involved in angiogenesis and tumor growth of various cancers, but its role in cervical cancer remains to be defined. We investigated the effects of bFGF on HeLa cell growth and studied its influence on the expression of angiogenin. We transfected the bFGF gene in the sense and antisense orientation into HeLa cells, and obtained stable bFGF underexpressing and overexpressing transfectants. In our experiments, we demonstrated that inhibition of bFGF gene and protein expression in the bFGF antisense transfectants induced increased protein expression of angiogenin. In contrast, in the bFGF sense transfectants the expression of angiogenin decreased. Delivery of recombinant angiogenin into transfected and control cells led to increased proliferation in the bFGF antisense transfectants and the control cells. However, the cell proliferation had no change in the bFGF sense transfectants. In conclusion, we demonstrated that besides its angiogenic activity, bFGF and angiogenin also directly contribute to HeLa cell proliferation. Furthermore, endogenous bFGF affects the expression of angiogenin in HeLa cells. These findings suggest that inhibition of bFGF alone is not a promising strategy to inhibit angiogenesis.

Detection of serum anti-p53 antibodies from patients with ovarian cancer in China: correlation to clinical parameters.

BACKGROUND: Ovarian cancer has been one of the most common malignant tumor among women in China. The aims of this research were to increase the detection efficiency of anti-p53 antibodies in the sera from patients with ovarian cancer and to assist the diagnosis for patients with ovarian cancer. METHODS: The hybrid phage displaying the immunodominant epitope SQAMDDLMLS in p53 N-terminal region was constructed and the fusion protein was prepared and purified. Ninety-two nonselected Chinese women with ovarian cancer were involved in this study. Tumor p53 overexpression was assessed by immunohistochemical analysis of tissue sections. Serum antibodies to p53 were also detected by enzyme-linked immunosorbent assay (ELISA) using recombinant human wild-type p53 protein and the hybrid phage as the coating antigen respectively. Furthermore, the correlations between the anti-p53 antibodies and clinicopathological parameters were analyzed. RESULTS: The positive rate of anti-p53 antibodies in the patients with ovarian cancer was increased (39.1%, 36/92) through the combination of the two ELISA methods compared with each method. The anti-p53 antibodies were not associated with the clinicopathologic parameters, while there was a significant correlation between the presence of p53 Abs and tissue overexpression of p53 in ovarian cancer. CONCLUSION: These preliminary results demonstrate that the combination of the two ELISA methods increased the positive rate of anti-p53 antibodies in patients with ovarian cancer and provided a useful marker to complement routine clinical diagnosis for patients with ovarian cancer.

Protective mechanism of desiccation tolerance in Reaumuria soongorica: leaf abscission and sucrose accumulation in the stem.

Reaumuria soongorica (Pall.) Maxim., a perennial semi-shrub, is widely found in semi-arid areas in northwestern China and can survive severe desiccation of its vegetative organs. In order to study the protective mechanism of desiccation tolerance in R. soongorica, diurnal patterns of net photosynthetic rate (Pn), water use efficiency (WUE) and chlorophyll fluorescence parameters of Photosystem II (PSII), and sugar content in the source leaf and stem were investigated in 6-year-old plants during progressive soil drought imposed by the cessation of watering. The results showed that R. soongorica was characterized by very low leaf water potential, high WUE, photosynthesis and high accumulation of sucrose in the stem and leaf abscission under desiccation. The maximum Pn increased at first and then declined during drought, but intrinsic WUE increased remarkably in the morning with increasing drought stress. The maximal photochemical efficiency of PSII (Fv/Fm) and the quantum efficiency of noncyclic electric transport of PSII (phiPSII) decreased significantly under water stress and exhibited an obvious phenomenon of photoinhibition at noon. Drought stressed plants maintained a higher capacity of dissipation of the excitation energy (measured as NPQ) with the increasing intensity of stress. Conditions of progressive drought promoted sucrose and starch accumulation in the stems but not in the leaves. However, when leaf water potential was less than -21.3 MPa, the plant leaves died and then abscised. But the stem photosynthesis remained and, afterward the plants entered the dormant state. Upon rewatering, the shoots reactivated and the plants developed new leaves. Therefore, R. soongorica has the ability to reduce water loss through leaf abscission and maintain the vigor of the stem cells to survive desiccation.

Effects of coffee and caffeine on bladder dysfunction in streptozotocin-induced diabetic rats.

AIM: To explore the effects and mechanisms of caffeine and coffee on bladder dysfunction in streptozotocin-induced diabetic rats. METHODS: Sprague-Dawley male rats were divided randomly into 4 groups: control, diabetes mellitus (DM), DM with coffee treatment, and DM with caffeine treatment. The diabetic rat was induced by intraperitoneal injection of streptozotocin (60 mg/kg). After 7 weeks of treatment with coffee and caffeine, cystometrogram, contractile responses to electrical field stimulation (EFS) and acetylcholine (ACh), and cyclic AMP (cAMP) concentration of the bladder body and base were measured. RESULTS: The bladder weight, volume threshold for micturition and post-void residual volume (PVR) in the diabetic rats were significantly higher compared to those in the control animals. Coffee or caffeine treatment significantly reduced the bladder weight, bladder capacity and PVR in the diabetic rats. DM caused significant decreases in cAMP concentration of the bladder and coffee and caffeine caused upregulation of cAMP content in the diabetic bladder. In addition, coffee and caffeine tended to normalize the altered detrusor contractile responses to EFS and ACh in the diabetic rats. CONCLUSION: These results indicate that caffeine and coffee may have beneficial effects on bladder dysfunction in the early stage of diabetes by increasing cAMP content in the lower urinary tract, recovering the micturition reflex and improving the detrusor contractility.