An experimental study on the relation between friction force and real contact area.

Classical laws of friction suggest that friction force is proportional to the normal load and independent of the nominal contact area. As a great improvement in this subject, it is now widely accepted that friction force is proportional to the real contact area, and much work has been conducted based on this hypothesis. In present study, this hypothesis will be carefully revisited by measuring the friction force and real contact area in-site and real-time at both normal loading and unloading stages. Our experiments reveal that the linear relation always holds between friction force and normal load. However, for the relation between friction force and real contact area, the linearity holds only at the loading stage while fails at the unloading stage. This study may improve our understanding of the origin of friction.

[Reference value of urine tangible component analyzer for healthy adults in Guangzhou area].

Objective: To establish the normal reference for iQ200 urine component analyzer of healthy adults in Guangzhou area. Methods: Five hundreds and four normal urine samples were screened from the healthy population with the normal dry chemistry results of urine and normal biochemical results of plasma, and the RBC, WBC and epithelial cells were determined by iQ200 urine component analyzer. Then 1 ml urine was accurately collected from the samples by centrifugation and the RBC, WBC and epithelial cells were counted with neubauer counter by two inspectors. The samples were divided into 4 groups according to the age (18-45 years and >45 years old) and sex (male and female). The counts of RBC, WBC and epithelial cell of 4 groups with iQ200 urine component analyzer and neubauer counter were statistically analyzed. Results: The difference was not significant in RBC, WBC and epithelial cells between the results of iQ200 urine component analyzer and the results of neubauer counter(all P>0.05). There was not significant difference of RBC, WBC and epithelial cells of the same sex and different age groups (all P>0.05). There was significant difference of RBC, WBC and epithelial cells between the different gender groups(all P<0.05). The 95% confidence interval reference range of iQ200 urine component analyzer were as follows: RBC 0-7 cells/µl (male), 0-8 cells/µl (female); WBC 1-6 cells/µl (male), 1-8 cells/µl (female); epithelial cells 0-2 cells/µl (male), 0-8 cells/µl (female). Conclusion: The reference of this research of iQ200 urine component analyzer will be useful for the laboratory and clinic, but still need the verification experiment before using in the laboratory.

[Relationship between phenotype and genotype of ABCB11 deficiency in siblings and literature review].

Objective: To explore the relationship between genotype and phenotype of ABCB11 deficiency. Methods: Clinical data of two siblings with ABCB11 deficiency were retrospectively analyzed. Related literature from PubMed, CNKI and Wangfang databases was reviewed to date (up to August 2017) with 'ABCB11 gene' or 'bile salt export pump', 'cholestasis' and 'child' as key words. Results: The patients were siblings. Both of them presented as jaundice, pruritus and hepatosplenomegaly since 3 days after birth. Significant laboratory findings on admission of the older sister included high total bilirubin, 170 µmol/L;conjugated bilirubin, 115.8 µmol/L;alanine aminotransferase, 168 U/L;total bile acid 186.3 µmol/L and normal gamma-glutamyl transpeptidase. While routine laboratory data of the younger brother were as follows: total bilirubin, 148.8 µmol/L;conjugated bilirubin, 96.3 µmol/L;alanine aminotransferase, 232.8 U/L;total bile acid 226 µmol/L, and normal gamma-glutamyl transpeptidase.Both received ursodeoxycholic acid and fat-soluble vitamins. Liver pathology of the younger brother showed giant hepatocytes with ballooning degeneration, focal necrosis and intrahepatic cholestasis. Both the patients harbor the same compound heterozygous mutations in ABCB11 gene, c.145C>T (p.Q49X) and c.1510G>A (p.E504K). The sister is 9 years old now, with normal liver function. Jaundice faded around 3 months after birth, pruritus relieved at age 5, and medications was stopped since then. The brother progressed to liver failure after an operation on perianal abscess when he was 8-month-old, and received living-related liver transplantation when he was 9 month and 20 days old (from his mother). Now he is 1 year and 5 months old, with normal liver function. Both are under our follow-up. Literature review revealed 18 ABCB11 deficiency patients from 7 families who had apparent different prognoses, within each family the siblings had the same ABCB11 gene mutation. Seven cases relieved after ursodeoxycholic acid therapy and/or partial external biliary diversion, 5 received orthotopic liver transplantation, 2 developed hepatocellular carcinoma and 4 cases died in childhood. Conclusions: The clinical manifestations of ABCB11 deficiency may vary greatly in patients carrying the same genotype, even in siblings. Patients should be managed in individualized maner.

[The relationship between the radioresistance of pancreatic cancer cell SW1990 and the induction of the Epithelial-Mesenchymal Transition: an in vitro study].

Objective: To investigate the relationship between the radioresistance of pancreatic cancer cell SW1990 and the induction of the Epithelial-Mesenchymal Transition (EMT). Methods: The radio-resistant pancreatic cancer cell SW1990-R were established by using the method of radiating pancreatic cancer cell SW1990 step by step and repeatedly. Then the changes of the morphology of the cell was observed by inverted phase contrast microscope, the radioresistance of SW1990-R was detected by colony-forming assay, and the apoptosis rate of the two cell lines after radiation were measured by flow cytometry. Then invasiveness and EMT-related genes was measured by trans-well test and qRT-PCR. Finally, the model of transplanted tumor on nude mouse was used to confirm the relationship between the radioresistance of pancreatic cancer cell SW1990 and the induction of EMT. Results: Compared with SW1990, SW1990-R had a lower radiosensitivity (survival fraction in 2 Gy, SF2: 0.326 3±0.007 3 vs 0.840 8±0.001 9, P<0.05) and lower apoptosis rate[(6.12±1.27) % vs (16.87±1.73)%, P<0.05]. Meanwhile, the invasive ability of SW1990-R were significant higher than that of SW1990 cell. According to the result of both in vivo and in vitro experiment, SW1990-R had a higher expression level of Vimentin and Snail, and lower expression level of E-cadherin when compared with SW1990. Conclusion: Compared with SW1990, the radio-resistant pancreatic cancer cell SW1990-R can induce the Epithelial-mesenchymal transition.

[Application of long term video electroencephalogram and resting-state functional magnetic resonance imaging in detection of cognition in patients with benign epilepsy of childhood with centrotemporal spikes].

Objective: To study the relationship between the changes of brain network and cognition in patients with benign epilepsy of childhood with centrotemporal spikes (BECTS) by using long term video electroencephalogram (VEEG) and resting-state functional magnetic resonance imaging (RS-fMRI) technology. Methods: Eleven patients with right-handed were recruited (from April 2015 to September 2016) from epilepsy specialist outpatients and functional department of neurosurgery of Tianjin Medical University General Hospital. They all underwent the long term VEEG monitoring (one sleep cycle was included at least). According to the spike-wave index (SWI) during slow ware sleep, they were divided into two groups: SWI<50% (5 cases) and SWI≥50% (6 cases). All the patients were assessed with cognitional test including language, execution, memory and attention. They also underwent the head MRI, RS-fMRI examinations. Then the results were comparatively analysed. Results: (1)There were no statisticaly significance in sex, age, age of onset, disease course, total number of seizures, years of education (P>0.05). The Full Intelligence Quotient (FIQ) (87±18), Verbal Intelligence Quotient (VIQ) (88±15) and Performance Intelligence Quotient (PIQ) (89±20) of SWI≥50% group were lower than SWI<50% group(118±8, 114±11, 119±5) and the differences were statistically significant(P<0.05). (2)There was a negative correlation between the FIQ (P=0.002), VIQ (P=0.006), PIQ (P=0.001) and SWI. The FIQ, VIQ and PIQ had no correlation with the sex, age, age of onset, disease course, total number of seizures, years of education (P>0.05). (3)Compared with SWI<50% group, SWI≥50% group showed increased regional homogeneity (ReHo) in the bilateral precentral gyrus, premotor area and the subcortical structure, the right temporal lobe and the bilateral insular lobe(P<0.05); while they showed decreased ReHo in the posterior cingulate gyrus, right posterior inferior temporal lobe and right occipital lobe(P<0.05). Conclusion: The change of the brain network which is caused by the paradoxical and constant discharge during slow ware sleep in patients with BECTS may affect the development of cognition.

An accelerated rabies vaccine schedule based on toll-like receptor 3 (TLR3) agonist PIKA adjuvant augments rabies virus specific antibody and T cell response in healthy adult volunteers.

BACKGROUND: Rabies is a fatal disease where post-exposure prophylaxis (PEP) is crucial in preventing infection. However, deaths even after appropriate PEP, have been reported. The PIKA Rabies vaccine adjuvant is a TLR3 agonist that activates B and T cells leading to a robust immune response. METHODS: We conducted a phase I, open label, randomized study in healthy adults to assess the safety and immunogenicity of the PIKA Rabies vaccine and an accelerated vaccine regimen. Thirty-seven subjects were randomized into 3 groups: control vaccine classic regimen, PIKA vaccine classic regimen and PIKA vaccine accelerated regimen. Subjects were followed up for safety, rabies virus neutralizing antibodies (RVNA) and T cell responses. RESULTS: Both the control and PIKA Rabies vaccine were well tolerated. All adverse events (AEs) were mild and self-limiting. Seventy-five percent of subjects in the PIKA accelerated regimen achieved a RVNA titer ⩾0.5IU/mL on day 7, compared to 53.9% in the PIKA classic regimen (p=0.411) and 16.7% in control vaccine classic regimen (p=0.012). The PIKA rabies vaccine elicited multi-specific rabies CD4 mediated T cell response already detectable ex vivo at day 7 after vaccination and that was maintained at day 42. CONCLUSION: The investigational PIKA rabies vaccine was well tolerated and more immunogenic than the commercially available vaccine in healthy adults. Clinical trial registry: The study was registered with clinicaltrials.gov NCT02657161.

IGFBP-3 A-202C and C2133G polymorphisms and colorectal cancer risk: a meta-analysis of case-control studies.

Recent evidence suggests that genetic variations in the IGFBP-3 gene may impact susceptibility to colorectal cancer, but individually published results are inconclusive. Our meta-analysis was aimed at providing a more precise estimation of these associations. An extensive literature search was conducted for appropriate articles published before May 1, 2013. This meta-analysis was performed using the STATA 12.0 software. The crude odds ratios (OR) with 95% confidence interval (CI) were calculated. Eleven case-control studies were included with a total of 11,895 colorectal cancer patients and 17,147 healthy controls. Our meta-analysis indicated that the G variant of IGFBP-3 C2133G polymorphism may be associated with increased colorectal cancer risk. However, no statistically significant association was noted between IGFBP-3 A-202C polymorphism and colorectal cancer risk. No publication bias was detected in this meta-analysis. The current meta-analysis suggests that the IGFBP-3 C2133G polymorphism may confer susceptibility to colorectal cancer. The G variant of the IGFBP-3 C2133G polymorphism may serve as a useful biomarker for predicting the risk of colorectal cancer.

HIF1A gene Pro582Ser polymorphism and susceptibility to digestive tract cancers: a meta-analysis of case-control studies.

Many existing studies have demonstrated that common polymorphisms in the hypoxia inducible factor-1α (HIF-1A) may contribute to the development of digestive tract cancers, but individually published studies showed inconclusive results. This meta-analysis aimed to derive a precise estimation of the relationships between HIF1A Pro582Ser polymorphism and the risk of digestive tract cancers. We searched CISCOM, CINAHL, Web of Science, PubMed, Google Scholar, EBSCO, Cochrane Library, and CBM databases from inception through May 1, 2013. Meta-analysis was performed using the STATA 12.0 software. We assessed 6 case-control studies that included a total of 911 digestive tract cancer patients and 2774 healthy controls. Our meta-analysis indicated that HIF1A Pro582Ser polymorphism was associated with an increased risk of digestive tract cancer. Subgroup analysis by ethnicity suggested that HIF1A Pro582Ser polymorphism might increase an individual's susceptibility to digestive tract cancer in Asian populations. However, similar association was not observed in Caucasian populations. In conclusion, our findings suggest that HIF1A Pro582Ser polymorphism may contribute to the risk of digestive tract cancers, especially in Asian populations.

Circular closure is associated with the lowest rate of surgical site infection following stoma reversal: a systematic review and multiple treatment meta-analysis.

AIM: Stoma reversal is frequently complicated by surgical site infection (SSI). To reduce SSI, several techniques for skin closure have been studied, with no agreement on which is best. The aim of this study was to identify the skin closure technique associated with the lowest rate of SSI following stoma reversal. METHOD: We systematically searched MEDLINE (PubMed and OvidSP), Scopus and clinical registries from 1 January 1980 to 24 March 2012, and included original reports on adult patients following stoma reversal. A network of treatments was created to map the comparisons between skin closure techniques, including primary closure, primary closure with a drain, secondary closure, delayed primary closure, loose primary closure and circular closure. Pairwise meta-analyses were performed for all available direct comparisons of closure types and heterogeneity was assessed. A multiple-treatments meta-analysis was conducted to estimate relative treatment effects between competing closure types (reported as an odds ratio with 95% credible interval, and a probability that each treatment is best). Several sensitivity analyses were performed. RESULTS: Fifteen studies were identified with a total of 2921 cases of stoma reversal. Overall, study quality was poor with observed low (one study), moderate (seven studies) and high (seven studies) risk of bias. Circular closure was associated with the lowest SSI risk (OR 0.12; 95% CI 0.02-0.40) and was the best of six skin closure techniques (probability of being best = 68.9%). Circular closure remained the best after sensitivity analyses. CONCLUSION: This study showed that circular closure is the best skin closure technique after stoma reversal in terms of SSI rate, but the quality of supporting evidence is limited, precluding definite conclusions.

Isolation and identification of renal cell carcinoma-derived peptides associated with GP96.

We determined the possible associated determinants and analyzed whether gp96-_associated antigenic peptides can be found in renal cell carcinoma (RCC). The gp96-peptide complexes were chromatographically purified from resected tumor tissue of RCC patients. SDS-PAGE and Western blot analysis confirmed gp96 using the gp96 monoclonal antibody, and its concentration was measured using BCA. Approximately 20 to 50 µg gp96-peptide complexes was obtained from 1 g RCC tissue. The mass spectrometry (MS) analysis of the eluted peptides included the initial profiling using matrix-assisted laser desorption/ionization time-of-flight MS. Quadrupole time-of-flight MS combined with the Mascot search engine was used to identify the peptides and find proteins from primary sequence databases. MS analysis results demonstrated that the mass range of peptide associated with gp96 was from 1046.48 to 3501.56 Da. Further research confirmed the sequences of two gp96-associated peptides, namely, LVPLEGWGGNVM and PPVYYVPYVVL. However, the original protein of the two peptides could not be found. The results demonstrated that the gp96-associated peptides are small molecular peptides, and the two peptides are deduced to be RCC-associated peptides. The identified peptides were confirmed to be associated with gp96 using the protocols described above. However, the specificity and relevance of the association to the immunogenicity of gp96 remains to be examined. Further analysis must be accomplished before the findings can be applied in peptide vaccine.

Transferability of Newly Developed Pear SSR Markers to Other Rosaceae Species.

A set of 120 simple sequence repeats (SSRs) was developed from the newly assembled pear sequence and evaluated for polymorphisms in seven genotypes of pear from different genetic backgrounds. Of these, 67 (55.8 %) primer pairs produced polymorphic amplifications. Together, the 67 SSRs detected 277 alleles with an average of 4.13 per locus. Sequencing of the amplification products from randomly picked loci NAUPy31a and NAUpy53a verified the presence of the SSR loci. When the 67 primer pairs were tested on 96 individual members of eight species in the Rosaceae family, 61.2 % (41/67) of the tested SSRs successfully amplified a PCR product in at least one of the Rosaceae genera. The transferability from pear to different species varied from 58.2 % (apple) to 11.9 % (cherry). The ratio of transferability also reflected the closer relationships within Maloideae over Prunoideae. Two pear SSR markers, NAUpy43c and NAUpy55k, could distinguish the 20 different apple genotypes thoroughly, and UPGMA cluster analysis grouped them into three groups at the similarity level of 0.56. The high level of polymorphism and good transferability of pear SSRs to Rosaceae species indicate their promise for application to future molecular screening, map construction, and comparative genomic studies among pears and other Rosaceae species.

Beneficial effects of the herbal medicine Di Huang Yin Zi in patients with spinal cord injury: a randomized, placebo-controlled clinical study.

OBJECTIVE: This study investigated the safety and therapeutic efficacy of Di Huang Yin Zi (DHYZ), a traditional Chinese decoction used to treat neurological disorders, in spinal cord injury (SCI). METHODS: In this double-blind, placebo-controlled study, patients with traumatic SCI and American Spinal Injury Association (ASIA) impairment grades B-D were randomized to receive DHYZ (n = 30) or placebo (n = 30) for 12 weeks. Both groups also received rehabilitation therapy during the study period. Motor and sensory function and activities of daily living (ADL) were assessed before treatment and at 4-week intervals. RESULTS: Significantly more patients in the DHYZ group showed an improved ASIA impairment grade during the treatment period (32.1%) compared with the placebo group (10.3%), and scores for sensory and motor function and ADL at the end of the treatment period were significantly higher in the DHYZ group than in the placebo group. No serious side-effects were reported. CONCLUSIONS: DHYZ was found to improve neurological function in patients with SCI and may be an effective adjuvant therapy to enhance functional recovery.

Strategies to improve the killing of tumors using temozolomide: targeting the DNA repair protein MGMT.

Alkylating agents such as temozolomide (TMZ) are effective anticancer drugs for treating a variety of solid tumors including melanoma, glioma, and astrocytoma. TMZ exerts its effects mainly via the mutagenic product O(6)-methylguanine, a cytotoxic DNA lesion. This damage may be repaired by the DNA repair enzyme O(6)-methylguanine DNA methyltransferase (MGMT), a key player in the resistance of cancers to TMZ. Several strategies are presently being pursued to improve the killing of tumor cells by TMZ, with inhibition of MGMT being the most promising. In this review, we provide an overview of recent advances in this field.

Design and implementation of a system with a multielement thermopile for monitoring temperature of a plane.

In this paper, we report the design of a system equipped with a multielement thermopile for measuring the temperature of a given plane. We evaluate the performance of our measurement system, which comprises a microcontroller, an analog-to-digital converter, a liquid crystal display (LCD), light-emitting diodes (LEDs), a buzzer, laser pointers, and a rotary encoder. We use different types of display modes such as an LCD for displaying the measured temperature, LEDs which colors indicate the temperature range, and an RS-232 or a wireless interface that transmits the temperature values to be displayed as different colors on a PC screen. The buzzer/alarm in the system is activated when the threshold temperature is reached. The system is inexpensive, portable, and can be used for two-dimensional temperature measurements; further, its emissivity can be easily adjusted. The effective detection range of this system is from -20 to 115 degrees C, and the field of view is 41 degrees x32 degrees ; the measurement error is confined to +/-1 degrees C. The experimental results demonstrate the effectiveness of the system in monitoring the temperature of a remote plane. Hence, it is possible to identify a hot spot that occurred in the electrical heating equipment or a smoldering source hidden in upholstery.

Retrospective analysis of thyroid nodules by clinical and pathological characteristics, and ultrasonographically detected calcification correlated to thyroid carcinoma in South China.

OBJECTIVE: To investigate the clinical and pathological characteristics of thyroid nodules, as well as to evaluate the significance of ultrasonographically detected thyroid calcification in the diagnosis of thyroid carcinomas. METHODS: Retrospective data were studied from 1,051 consecutive patients who underwent a thyroidectomy in the Provincial Hospital of Fujian Medical University in South China between January 2003 and July 2006 for nodular thyroid disease. Complete sonographical information before surgery was only collected from 758 of the 1,051 patients. RESULTS: Among the 1,051 patients, benign lesions were found in 857 (81.54%) patients, of whom 612 (71.41%) were nodular goiter; malignant lesions were found in 194 (18.46%) patients, in whom benign thyroid lesions were also found in 85 (43.81%) patients. A total of 48 patients suffered from microcarcinomas, of whom 37 patients had benign lesions; these 37 accounted for 43.53 and 77.08%, respectively, of the 85 malignant cases with benign lesions and the 48 cases with microcarcinomas. In the 758 patients who underwent thyroid ultrasonography before surgery, intrathyroidal calcifications were apparent in 243 patients (32.06%). The incidence of calcification was significantly higher in patients with thyroid carcinoma (54.17%) than in those with benign lesions (26.87%; p < 0.005). Detection of calcification in thyroid lesions by ultrasound had a sensitivity of 32.38% and a specificity of 87.35%, with an OR of 3.31 (95% CI, 2.24-4.63), positive likelihood ratio of 2.56, negative likelihood ratio of 0.77 and a kappa value of 0.23. CONCLUSION: Thyroid carcinoma, especially microcarcinoma, often coexists with benign thyroid disease. Calcification detected by thyroid ultrasound represents a risk factor for malignancy, but is of limited use as a sole marker of malignancy.

Isolation, characterization and identification of lactic acid bacteria and yeasts from sour Mifen, a traditional fermented rice noodle from China.

AIMS: Considering the effect of natural fermentation on the textural improvement of fermented rice noodles in China and South Asia, and given the lack of reports concerning microbial populations and structure in the fermentation process, this study aims to determine the number of viable micro-organisms and identify the species isolated from the local factories, and to assess their potential use as a starter culture from their enzymatic profiles. METHODS AND RESULTS: Fourteen samples from three local factories were analysed for the presence of micro-organisms. A total of 170 lactic acid bacteria (LAB) and 96 yeasts were isolated from the factories. The isolates were phenotypically characterized by using API 50 CHL kits, API 20 Strep kits, API ID 32 C kits and by performing additional biochemical tests. The enzymatic profiles of isolates were assessed by using API ZYM kits. Lactobacillus plantarum and Saccharomyces cerevisiae were identified as predominant species in the fermented supernatants. A majority of the isolates of LAB and yeasts displayed activities of alpha-glucosidase, beta-glucosidase, lipase and trypsin. CONCLUSIONS: The microbial composition and strain characteristics present in the fermentation supernatant demonstrate that a majority of micro-organisms have the ability to digest starch, sugar, protein or lipid. It supports our previous work in which the rice starch was modified and purified by fermentation and thus improves the texture of rice noodles. SIGNIFICANCE AND IMPACT OF THE STUDY: The dominant strains would be important in developing a starter culture. The results can form the basis for the improvement of product quality and consistency.

Radical scavenging activity and phenolic compounds in persimmon (Diospyros kaki L. cv. Mopan).

The Mopan persimmon (Diospyros kaki L. cv. Mopan) is the major cultivar of astringent persimmon in northern China. This study investigates the radical scavenging activity against ABTS and DPPH radical, and the content of total and individual phenolics (catechin, epicatechin, epigallocatechin, chlorogenic acid, caffeic acid, and gallic acid) with apple, grape, and tomato as controls. The radical scavenging activities against ABTS and DPPH radicals of the Mopan persimmon are 23.575 and 22.597 microm trolox eq/g f.w., respectively. These findings suggest that the Mopan persimmon's antioxidant activity is significantly (P < 0.05) stronger than that of reference materials. The Mopan persimmon showed the highest content of total phenolics among the 4 materials tested. Significant correlations (R(2)= 0.993, P < 0.05, ABTS radical; R(2)= 0.980, P < 0.05, DPPH radical) are found between the total phenolics and the radical scavenging activities. The total content of these 6 kinds of phenolics (catechin, epicatechin, epigallocatechin, chlorogenic acid, caffeic acid, and gallic acid) is significantly correlated (R(2)= 0.831, P < 0.05, ABTS radical; R(2)= 0.745, P < 0.05, DPPH radical) with the individual radical scavenging activity of the 4 materials, although the total content of the 6 phenolics accounts for no more than 20% of the total phenolics in the Mopan persimmon. Gallic acid exhibits the strongest antioxidant activity in all 6 kinds of phenolics and its content is the largest in the Mopan persimmon, presumably being responsible for its much higher antioxidant activity as compared to apple, grape, and tomato.

A xylose-tolerant beta-xylosidase from Paecilomyces thermophila: characterization and its co-action with the endogenous xylanase.

An extracellular beta-xylosidase from the thermophilic fungus Paecilomyces thermophila J18 was purified 31.9-fold to homogeneity with a recovery yield of 2.27% from the cell-free culture supernatant. It appeared as a single protein band on SDS-PAGE with a molecular mass of approx 53.5 kDa. The molecular mass of beta-xylosidase was 51.8 kDa determined by Superdex 75 gel filtration. The enzyme was a glycoprotein with a carbohydrate content of 61.5%. It exhibited an optimal activity at 55 degrees C and pH 6.5, respectively. The enzyme was stable in the range of pH 6.0-9.0 and at 55 degrees C. The purified enzyme hydrolyzed xylobiose and higher xylooligosaccharides but was inactive against xylan substrates. It released xylose from xylooligosaccharides with a degree of polymerization ranging between 2 and 5. The rate of xylose released from xylooligosaccharides by the purified enzyme increased with increasing chain length. It had a K(m) of 4.3mM for p-nitrophenol-beta-d-xylopyranoside and was competitively inhibited by xylose with a K(i) value of 139 mM. Release of reducing sugars from xylans by a purified xylanase produced by the same organism increased markedly in the presence of beta-xylosidase. During 24-hour hydrolysis, the amounts of reducing sugar released in the presence of added beta-xylosidase were about 1.5-1.73 times that of the reaction employing the xylanase alone. This is the first report on the purification and characterization of a beta-xylosidase from Paecilomyces thermophila.