Rapid Detection of Bacterial Pathogens Causing Lower Respiratory Tract Infections via Microfluidic-Chip-Based Loop-Mediated Isothermal Amplification

Respiratory tract infections (RTIs) are among the most common problems in clinical settings. Rapid and accurate identification of bacterial pathogens will provide practical guidelines for managing and treating RTIs. This study describes a method for rapidly detecting bacterial pathogens that cause respiratory tract infections via multi-channel loop-mediated isothermal amplification (LAMP). LAMP is a sensitive and specific diagnostic tool that rapidly detects bacterial nucleic acids with high accuracy and reliability. The proposed method offers a significant advantage over traditional bacterial culturing methods, which are time-consuming and often require greater sensitivity for detecting low levels of bacterial nucleic acids. This article presents representative results of K. pneumoniae infection and its multiple co-infections using LAMP to detect samples (sputum, bronchial lavage fluid, and alveolar lavage fluid) from the lower respiratory tract. In summary, the multi-channel LAMP method provides a rapid and efficient means of identifying single and multiple bacterial pathogens in clinical samples, which can help prevent the spread of bacterial pathogens and aid in the appropriate treatment of RTIs.

A Case of Invasive Fungal Infection Due to Scedosporium apiospermum in a Patient with Psoriasis

Scedosporium apiospermum (S. apiospermum) is typically reported to be involved in superficial and subcutaneous fungal infections but overlooked in invasive infections, which is associated with a high mortality rate. It poses a diagnostic challenge due to its confusable characteristics to other hyaline hyphomycetes. Here, we reported a psoriasis patient with an invasive S. apiospermum infection. The patient presents an abscess at the intermuscular space of the left hip and an increased C-reactive protein level. Pus culture showed white-greyish, cottonlike colonies with aerial mycelium and terminal oval conidia, suggesting S. apiospermum. This rare fungus was rapidly confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and RNA sequencing. The patient was successfully treated with voriconazole with no recurrence of the abscesses despite delayed treatment. This is the first such case infection report from China that described an unusual case of intermuscular space abscesses due to S. apiospermum. This report highlights the possibility of fungal infections in deeper tissue, as well as the necessity of thorough evaluation and microbiological diagnosis for invasive infections, particularly in immunocompromised patients.

[Effects of three methods for correction of low-degree against-the-rule corneal astigmatism during cataract surgery]

Objective: To compare the clinical effects of and visual quality after correction of low-degree against-the-rule (ATR) corneal astigmatism by implantation of an astigmatism-corrected intraocular lens (IOL), femtosecond laser release and manual release in cataract surgery. Methods: It was a prospective cohort study. A total of 120 patients (120 eyes) with cataract combined with low-degree ATR corneal astigmatism diagnosed in Chongqing Aier Mega Eye Hospital from December 2017 to October 2020 were included and divided into 3 groups, each with 40 patients, according to their own selections of astigmatism correction methods during cataract surgery. In the astigmatism-corrected IOL group, phacoemulsification for cataract extraction combined with toric IOL implantation was performed. In the femtosecond laser release group, astigmatic keratotomy using a femtosecond laser was combined. In the manual release group, a limbal relaxing incision was made. Uncorrected distance visual acuity (UDVA) and corneal astigmatism were measured before surgery. At 3 months and 1 year after surgery, UDVA and best-corrected distance visual acuity were examined, as well as whole eye residual astigmatism by ARK-1, corneal astigmatism by the IOLMaster 500, whole eye high order aberration (HOA) and modulation transfer function (MTF) by the iTrace visual function analyzer. Analysis of variance was used for the comparison of data in a normal distribution. Repeated measures were used for the comparison within groups. The rank sum test was used for the comparison of data that were not normally distributed. Results: Of the 120 patients, 100 patients (100 eyes), including 44 males and 56 females, with an age of (66.48±6.20) years, completed the follow-up. Among the three groups, the differences were not statistically significant in terms of gender distribution, age, preoperative corneal astigmatism, UDVA and spherical equivalent of the IOL (all P>0.05). At 3 months and 1 year after surgery, the UDVA was significantly better than that before surgery in each group (Z=5.18, 5.04, 4.98, 4.99, 4.90, 4.89; all P<0.001). At the two time points, the differences in the whole eye residual astigmatism among the three groups were statistically significant (H=30.69, 31.23; both P<0.001). At 3 months, the whole eye residual astigmatism in the astigmatism-corrected IOL group was lower than that in the other two groups. At 1 year, the residual astigmatism in the astigmatism-corrected IOL group [0.25(0.00, 0.50) D] was also lower compared to that in the femtosecond laser release group [0.50(0.50, 0.75) D] and the manual release group [0.75(0.50, 0.75) D] (Z=-3.71, -5.18, -3.94, -5.15; all P<0.001). The differences in the HOA at 3 months and 1 year among the three groups were statistically significant (H=36.30, 34.38; both P<0.001). The HOA in the astigmatism-corrected IOL group was significantly higher than that in the other two groups at the two time points (Z=5.01, 4.73, 5.31, 5.27; all P<0.001). At 3 months and 1 year, the differences in the MTF value among the three groups were also statistically significant (H=30.02, 29.92; both P<0.001), and the MTF value in the femtosecond laser release group was significantly higher than that in the other two groups (Z=4.61, 4.67, 4.66, 4.69; all P<0.001). Conclusions: All the three astigmatism correction methods used at the time of cataract surgery can effectively correct low-degree ATR corneal astigmatism. The residual astigmatism in the whole eye after astigmatism-corrected IOL implantation is small and stable, while the HOA after release using the femtosecond laser is low with good visual quality.

Case Report: Double trouble: a rare case of successfully treated Mycoplasma hominis and Pseudomonas aeruginosa co-infection

Background

Extra-urogenital infections due to Mycoplasma hominis (M. hominis) are rare, particularly co-infection with Pseudomonas aeruginosa (P. aeruginosa). Herein, we report on a patient who was co-infected and successfully treated despite delayed treatment.

Case presentation

We reported the case of a 43-year-old man with M. hominis and P. aeruginosa co-infection after a traffic accident. The patient developed a fever and severe infection despite postoperative antimicrobial therapies. The blood culture of wound tissues was positive for P. aeruginosa. Meanwhile, culturing of blood and wound samples showed pinpoint-sized colonies on blood agar plates and fried-egg-type colonies on mycoplasma medium, which were identified as M. hominis by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) and 16S rRNA sequencing. Based on antibiotic susceptibility and symptoms, ceftazidime-avibactam and moxifloxacin were administered for P. aeruginosa infection. Meanwhile, after the failure of a series of anti-infective agents, M. hominis and P. aeruginosa co-infection was successfully treated with a minocycline-based regimen and polymyxin B.

Conclusion

The co-infection with M. hominis and P. aeruginosa was successfully treated with anti-infective agents despite delayed treatment, providing information for the management of double infection.

Catheter-related infections caused by Mycobacterium abscessus in a patient with motor neurone disease: A case report

BACKGROUND

Mycobacterium abscessus (M. abscessus) is a rapidly growing mycobacterium and ubiquitous in the environment, which infrequently causes disease in humans. However, it can cause cutaneous or respiratory infections among immunocompromised hosts. Due to the resistance to most antibiotics, the pathogen is formidable and difficult-to-treat.

CASE SUMMARY

Here, we present a case of catheter-related M. abscessus infections in a patient with motor neurone disease. Catheter and peripheral blood cultures of the patient showed positive results during Gram staining and acid-fast staining. The alarm time of catheter blood culture was 10.6 h earlier than that of peripheral blood. After removal of the peripherally inserted central catheter, secretion and catheter blood culture were positive. M. abscessus was identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry and 16S rDNA sequencing.

CONCLUSION

For catheter-related M. abscessus infection, rapid diagnosis and timely and adequate antimicrobial therapy are crucial.

[Epidemic situation of malaria in Yunnan Province from 2014 to 2019]

OBJECTIVE

To investigate the epidemiological characteristics of malaria and implementation of the "1-3-7" approach in malaria elimination in Yunnan Province, so as to provide the data support for the development of post-elimination surveillance interventions.

METHODS

All data pertaining to malaria cases in Yunnan Province from 2014 to 2019 were captured from the Notifiable Disease Reporting System of Chinese Center for Disease Control and Prevention, and the changes in the epidemic situation of malaria were analyzed during the 5-year period. In addition, the core indexes regarding the "1-3-7" approach in malaria elimination of Yunnan Province from 2014 to 2019 were retrieved from the Malaria Control System in the Parasitic Disease Information Reporting System, and all changes in the indexes were descriptively analyzed.

RESULTS

During the period from 2014 to 2019, a total of 2 283 malaria cases were reported in Yunnan Province, including 1 927 cases with vivax malaria, 326 cases with plasmodium malaria, 29 cases with other species of malaria, and one case with unidentified species. There were 64 local cases, 2 219 overseas imported cases. Among the 2 283 malaria cases, the male/female ratio was 4.58∶1, and 80.25% of the cases were aged from 15 to 50 years. Farmer (70.00%) was the predominant occupation, and 76.70% (1 751/2 283) of the cases were identified in 25 border counties (districts). Malaria cases were reported in each month during the 5-year period, and the number of malaria cases increased from April, peaked on May to July, and started to decline on August. From 2014 to 2019, the reporting rate of malaria cases within 24 hours upon diagnosis was 100%, and the detection of malaria cases was 99.69% (2 276/ 2 283) in the laboratory, with a 99.65% (2 275/2 283) rate of definite diagnosis. In addition, the percentage of individual epidemiological investigations within 3 days was 100.00% (2 283/2 283), and the number of epidemic foci survey and treatment within 7 days was 576 during the 3-year period from 2017 to 2019. The goal of malaria elimination was achieved in Yunnan Province on June, 2020.

CONCLUSIONS

Malaria has been eliminated in Yunnan Province, and management of overseas imported malaria is the primary challenge to consolidate the malaria elimination achievements in the future. However, the approach in malaria elimination remains to be maintained, and the role of the Yunnan Provincial Malaria Diagnostic Reference Laboratory requires to be strengthened.

Reference intervals for thyroid-stimulating hormone and thyroid hormones using the access TSH 3rd IS method in China

Background

To calculate the reference intervals for thyroid‐stimulating hormone (TSH) and thyroid hormones using the Access TSH 3rd IS method and evaluate the differences between age and genders in Chinese populations.

Methods

This study collected 349 serum samples of healthy subjects were from Shengli Oilfield Central Hospital in China. Subjects who tested positive for thyroid peroxidase antibody or thyroglobulin antibody were excluded. Accordingly, 313 subjects were included for establishing reference intervals for the thyroid hormones. The serum concentrations of TSH, total and free thyroxine (TT4 and FT4), and total and free triiodothyronine (TT3 and FT3) were measured using the Access TSH 3rd IS method. The 2.5th and 97.5th percentiles or mean with standard deviation were calculated as the reference interval as appropriate.

Results

The reference intervals for TSH, FT4, FT3, TT4, and TT3 calculated in present study were 0.61‐4.16 mIU/L, 0.67‐1.11 ng/dL, 2.63‐4.33 pg/mL, 5.56‐11.33 μg/dL, and 0.72‐1.32 ng/mL, respectively. The FT3, TT4, and TT3 levels in males were significantly higher than in females (P < .05), while TSH levels in males were significantly lower than in females (P < .05). The levels of FT3 in subjects with the age of less than 30 years were significantly higher than other groups (P < .05).

Conclusion

The present study provided a valid basis for the reference intervals for TSH, FT4, FT3, TT4, and TT3 in Chinese populations. In addition, this present study indicated that age and gender should be considered in diagnostic evaluation of thyroid diseases.

Risk factors for flat anterior chamber after glaucoma filtration surgery

AIM

To investigate the incidence rate and risk factors for grade III flat anterior chamber (FAC) after glaucoma filtration surgery based on 5-year data.

METHODS

Patients who underwent glaucoma filtration surgery in Daping hospital from January 2009 to December 2013 were enrolled in this retrospective study. The incidence of grade III FAC following glaucoma filtration surgery was determined. Regression analysis was performed to investigate the influence of glaucoma type, surgical approach, age, and preoperative intraocular pressure (IOP) on the risk of postoperative FAC.

RESULTS

A total of 2179 eyes receiving anti-glaucoma surgery were included. Ninety-one eyes suffered from postoperative FAC, with an overall incidence rate of 4.18%. Of 471 eyes with primary open angle glaucoma (POAG), grade III FAC occurred in only 3 eyes (0.64%). Primary angle-closure glaucoma (PACG) was diagnosed in 1076 eyes, 39 (3.62%) of which developed grade III FAC, including 12 eyes (12/300, 4%) with acute PACG (aPACG) and 27 eyes (27/776, 3.48%) with chronic PACG (cPACG). Six of 259 eyes (2.32%) with secondary glaucoma, 28 of 186 eyes (15.05%) with neovasular glaucoma, 1 of 66 eyes (1.52%) with congenital glaucoma, and 14 of 115 eyes (12.17%) with remnant glaucoma suffered from grade III FAC. Of 6 eyes with mixed glaucoma, none developed grade III FAC after surgery. When stratified by surgical approach, 24 of 766 eyes (3.13%) undergoing trabeculectomy, 21 of 924 eyes (2.27%) treated by trabeculectomy plus mitomycin C (MMC), 18 of 109 eyes (16.51%) undergoing Ahmed glaucoma valve implantation, 23 of 201 eyes (11.44%) managed by Ahmed implantation plus MMC, and 5 of 133 eyes (3.76%) treated by Ahmed implantation plus lens extraction or vitrectomy developed grade III FAC. Logistic regression analysis revealed that factors including neovasular glaucoma, remnant glaucoma, glaucoma valve implantation, glaucoma valve implantation+MMC, glaucoma valve implantation+vitrectomy, age>60y, and IOP at admission >50 mm Hg were significantly associated with an increased risk for grade III FAC.

CONCLUSION

The overall incidence of grade III FAC after glaucoma filtration surgery is 4.18%. Patients with neovasular glaucoma and remnant glaucoma are at a higher risk of developing FAC. Ahmed glaucoma valve implantation is associated with a higher risk for grade III FAC compared with trabeculectomy. No significant correlation was observed between the use of MMC in glaucoma filtration surgery and the risk of postoperative FAC. Higher IOP at admission (>50 mm Hg) and old age (>60y) are risk factors for grade III FAC.

A feasibility study of using biodegradable magnesium alloy in glaucoma drainage device

Technological advances in glaucoma have challenged the traditional treatment paradigm. Historically incisional surgery has been used in cases of advanced disease and/or uncontrolled intraocular pressures resistant to medical or laser interventions. More recently, perhaps due to advancements in imaging, surgery has been suggested to be beneficial earlier in the treatment paradigm. Despite these trends, surgical manipulation of the tissues and unpredictability of wound healing continue to result in surgical failure. Magnesium is an essential element for human body and plays a critically important role in maintaining the functional and structural integrity of several tissues, including the eye. Due to several of its advantageous properties such as non-toxicity, biodegradability, and high biological compatibility, magnesium alloy has attracted great attention as a novel biomaterial. Biodegradable cardiovascular stents made of magnesium alloy have already been introduced into clinical practice. The purpose of this review is to determine if bioabsorbable magnesium alloys can be utilized as a promising candidate for the development of a new generation of glaucoma surgical assistive devices.

Influence of sleep disorders on somatic symptoms, mental health, and quality of life in patients with chronic constipation

BACKGROUND

Sleep disturbance is a common symptom in CC patients, and it is positively related to greater somatic and psychiatric symptoms.

METHODS

The participants were 126 adult outpatients with CC. The measures were: constipation-Constipation Scoring System (CSS) and Patient Assessment of Constipation-Symptoms (PAC-SYM); sleep-Pittsburgh Sleep Quality Index (PSQI); anxiety-General Anxiety Disorder-7 (GAD-7); depression-Patient Health Questionnaire-9 (PHQ-9); and QOL-Patient Assessment of Constipation Quality of Life (PAC-QOL) and SF-36. Patients were divided into sleep-disorder and normal-sleep groups by their PSQI scores.

RESULTS

The sleep-disorder group had significantly higher rates of incomplete defecation and blockage and higher CSS scores, PAC-SYM total scores, and PAC-SYM rectal-item scores than the normal-sleep group. GAD-7 and PHQ-9 scores were significantly higher in patients with poor sleep. Furthermore, sleep disorders, depression, and anxiety were all positively correlated with constipation severity. "Worry/anxiety" score of PAC-QOL scale was significantly higher and scores for seven SF-36 subscales were significantly lower in patients with poor sleep. In addition, correlation analyses showed significant negative relations between QOL and constipation, sleep disturbance, anxiety as well as depression. However, multiple regression revealed that PAC-QOL was positively associated with severe constipation and SF-36 was negatively associated with anxiety and depression. But sleep disturbance was not the independent risk factor for QOL of CC patients.

CONCLUSION

Sleep disorders may worsen the physical- and mental health of CC patients. Sleep disturbance may lower CC patients' QOL indirectly through the combined effects of anxiety, depression, and constipation.

Estrogen regulates the expression of small-conductance Ca-activated K+ channels in colonic smooth muscle cells

AIM

This study aimed to determine the effects of small-conductance Ca(2+)-activated K(+) (SK) channels in colonic relaxation and the regulation of SK channels by estrogen.

METHODS

The contractile activity of muscle strips from male rats was estimated, and drugs including vehicle (DMSO), 17β-estradiol (E2), or apamin (SK blocker) were added, respectively. In a further experiment, muscle strips were preincubated with apamin before exposure to E2. The levels of the SK2 and SK3 protein expression in the colonic smooth muscle cells (SMCs) were detected. SMCs were treated with ICI 182780 (estrogen receptor [ER] antagonist) plus E2, BSA-E2, PPT (ERα agonist), or DPN (ERβ agonist). SK3 mRNA and protein expression levels were detected.

RESULTS

The muscle strips responded to E2 with a decrease and to apamin with a transient increase in tension. Preincubation with apamin partially prevented E2-induced relaxation. Two SK channel subtypes, SK2 and SK3, were coexpressed with α-actin in colonic SMCs. The quantitative ratio of the SK transcriptional expression in colonic SMCs was SK3 > SK2. The SK3 expression was upregulated by E2, and was downregulated by ICI 182780, but was not influenced by BSA-E2. Furthermore, the effect of PPT on the expression of SK3 was almost the same as that of E2, while DPN did not influence the protein expression of SK3.

CONCLUSION

These findings indicate that SK3 is involved in the E2-induced relaxing effect on rat colonic smooth muscle. Furthermore, E2 upregulates the expression of SK3 in rat SMCs, and that this effect is mediated via the ERα receptor.

Role of estrogen in diabetic gastroparesis

Gastroparesis is a highly prevalent chronic disorder of the stomach, which is characterized by delayed gastric emptying and accompanied by a series of upper gastrointestinal symptoms. Diabetic gastroparesis (DGP) is one of the severe complications of diabetes, seriously affecting the patient's quality of life. At present, the pathogenesis of DGP is still unclear. The majority of DGP patients are women, and women's symptoms change with the fluctuation of the level of estrogen. Therefore, we speculate that estrogen may play an vital role in the stomach motility. Gastric emptying is an objective index for the diagnosis of gastroparesis. This article reviews the role of estrogen in DGP and the possible mechanisms.

Effect of endogenous insulin-like growth factor and stem cell factor on diabetic colonic dysmotility

AIM: To investigate whether the reduction of stem cell factor (SCF) is mediated by decreased endogenous insulin-like growth factor (IGF)-1 in diabetic rat colon smooth muscle.

METHODS: Sixteen Sprague-Dawley rats were randomly divided into two groups: control group and streptozotocin-induced diabetic group. After 8 wk of streptozotocin administration, colonic motility function and contractility of circular muscle strips were measured. The expression of endogenous IGF-1 and SCF was tested in colonic tissues. Colonic smooth muscle cells were cultured from normal adult rats. IGF-1 siRNA transfection was used to investigate whether SCF expression was affected by endogenous IGF-1 expression in smooth muscle cells, and IGF-1 induced SCF expression effects were studied. The effect of high glucose on the expression of endogenous IGF-1 and SCF was also investigated.

RESULTS: Diabetic rats showed prolonged colonic transit time (252 ± 16 min vs 168 ± 9 min, P < 0.01) and weakness of circular muscle contraction (0.81 ± 0.09 g vs 2.48 ± 0.23 g, P < 0.01) compared with the control group. Endogenous IGF-1 and SCF protein expression was significantly reduced in the diabetic colonic muscle tissues. IGF-1 and SCF mRNA expression also showed a paralleled reduction in diabetic rats. In the IGF-1 siRNA transfected smooth muscle cells, SCF mRNA and protein expression was significantly decreased. IGF-1 could induce SCF expression in a concentration and time-dependent manner, mainly through the extracellular-signal-regulated kinase 1/2 signal pathway. High glucose inhibited endogenous IGF-1 and SCF expression and the addition of IGF-1 to the medium reversed the SCF expression.

CONCLUSION: Myopathy may resolve in colonic motility dysfunction in diabetic rats. Deficiency of endogenous IGF-1 in colonic smooth muscle cells leads to reduction of SCF expression.

Five-year follow-up of 263 cases of functional bowel disorder

AIM: To determine the mortality associated with functional bowel disorders (FBDs) and their possible relationship with organic bowel disease.

METHODS: Patients who satisfied the Rome III criteria for FBD (retrospective diagnosis) were followed up by telephone interview and/or outpatient review at 5 years after their first attendance. The patients were divided into the following groups: irritable bowel syndrome, functional abdominal bloating, functional constipation, functional diarrhea and unspecified FBD. The survival of the FBD patients overall and of those with each FBD were compared with data obtained from the Guangzhou population in 2005. The incidences of colonic cancer overall and for each FBD were compared with data from the Chinese population obtained from 56 cancer registries in 19 provinces of the country in 2008.

RESULTS: Two hundred and sixty-three patients were followed-up. Five patients died, which was not significantly different from the expected survival rate. No differences in mortality among the FBDs were found. There were nine cases of organic bowel disease: three colonic cancers and six colonic polyps. The incidence of colonic cancer in FBD patients was higher than that in the general Chinese population (0.23% vs 0.03%, P < 0.05). There were significant differences in the incidence of colonic cancer among the FBDs (0/134, 0/24, 2/29, 1/66, 0/10, respectively, P < 0.05); functional constipation was the most common. The incidence of colonic polyps was similar among the FBDs. The baseline age of patients who died was greater than that of those who survived (66.60 ± 6.84 years vs 45.14 ± 10.34 years, P < 0.05). The baseline age of patients who had colonic cancer or polyps during follow-up was greater than that of those without colonic cancer or polyps (60.33 ± 1.53 years vs 45.38 ± 10.62 years; 54.50 ± 6.47 years vs 45.34 ± 10.68 years, P < 0.05).

CONCLUSION: FBDs do not increase the risk of death. The incidence of colonic cancer in patients with FBDs may be increased, especially in those with functional constipation and in the elderly.

Age-related symptom and life quality changes in women with irritable bowel syndrome

AIM

To explore age-related changes in symptoms and quality of life (QoL) of women with irritable bowel syndrome (IBS).

METHODS

Two-hundred and fifty-four female adult outpatients with IBS attending the Department of Gastroenterology at the First Affiliated Hospital of Nanjing Medical University between January, 2008 and October, 2008 were approached. Patients with a history of abdominal surgery, mental illness or those who had recently taken psychotropic drugs were excluded. A physician obtained demographic and abdominal symptom data. All patients were asked to complete the Zung Self-Rated Anxiety and Depression Scale (SDS/SAS) and the IBS-specific QoL questionnaire. The patients were divided into six groups according to age, in 10-year increments: 18-27 years, 28-37 years, 38-47 years, 48-57 years, 58-67 years and 68-75 years (maximum 75 years). Age-related differences of abdominal pain or discomfort were analyzed using rank-sum tests. Differences in SDS/SAS and IBS-QoL scores between age groups were analyzed using one-way analysis of variance. Pearson's correlations evaluated potential associations between IBS symptoms, psychological factors and QoL in each age group.

RESULTS

There were no differences in the distribution of IBS subtypes between age groups (χ(2) = 20.516, P = 0.153). Differences in the severity of abdominal pain/discomfort with age were statistically significant (χ(2) = 25.638, P < 0.001); patients aged 48-57 years, 58-67 years or 68-75 years had milder abdominal pain/discomfort than those in the younger age groups. The severity of anxiety or depressive symptoms did not differ between age groups (SDS, χ(2) = 390.845, P = 0.110; SAS, χ(2) = 360.071, P = 0.220). Differences of IBS-QoL scores were statistically significant between age groups (χ(2) = 1098.458, P = 0.011). The scores of patients in the 48-57-year group were lower than those in the 18-27-year and 28-37-year groups (48-57-year group vs 18-27-year group, 74.88 ± 8.76 vs 79.76 ± 8.63, P = 0.021; 48-57-year group vs 28-37-year group, 74.88 ± 8.76 vs 79.04 ± 8.32, P = 0.014). The scores in the 68-75-year group were lower than those in the 18-27-year, 28-37-year and 38-47-year groups (68-75-year group vs 18-27-year group, 71.98 ± 9.83 vs 79.76 ± 8.63, P = 0.003; 68-75-year group vs 28-37-year group, 71.98 ± 9.83 vs 79.04 ± 8.32, P = 0.002; 68-75-year group vs 38-47-year group,71.98 ± 9.83 vs 76.44 ± 8.15, P = 0.039). Anxiety and depression were negatively correlated with QoL in all age groups (SDS and QoL: 18-27-year group, r = -0.562, P = 0.005; 28-37-year group, r = -0.540, P < 0.001; 38-47-year group, r = -0.775, P < 0.001; 48-57-year group, r = -0.445, P = 0.001; 58-67-year group, r = -0.692, P < 0.001; 68-75-year group, r = -0.732, P < 0.001. SAS and QoL: 18-27-year group, r = -0.600, P = 0.002; 28-37-year group, r = -0.511, P < 0.001; 38-47-year group, r = -0.675, P < 0.001; 48-57-year group, r = -0.558, 58-67-year group, P = 0.001; r = -0.588, P < 0.001; 68-75-year group, r = -0.811, P < 0.001). A negative correlation between abdominal pain severity and QoL was found in patients aged more than 58 years (58-67-year group, r = -0.366, P = 0.017; 68-75-year group, r = -0.448, P = 0.048 ), but not in younger patients (18-27-year group, r = 0.080, P = 0.716; 28-37-year group, r = -0.063, P = 0.679; 38-47-year group, r = -0.029, P = 0.812; 48-57-year group, r = -0.022, P = 0.876).

CONCLUSION

Factors affecting QoL should always be treated in IBS, especially emotional problems in young adults. Even mild abdominal pain should be controlled in elderly patients.

Influence of insomnia and insomnia-related psychological factors on symptoms of female patients with irritable bowel syndrome

AIM: To investigate the influence of insomnia and insomnia-related psychological factors on the symptoms of female patients with irritable bowel syndrome (IBS).

METHODS: Two hundred and forty-five adult female outpatients with IBS who were treated at the Department of Gastroenterology of the First Affiliated Hospital of Nanjing Medical University were included in this study. A questionnaire survey was conducted using a demographic information questionnaire, a symptom questionnaire, athens insomnia scale (AIS), self-rating anxiety scale (SAS), and self-rating depression scale (SDS). According to AIS scores, female patients with IBS were divided into insomnia group and non-insomnia group. The influence of insomnia on typical symptoms, somatic symptoms and psychological symptoms of IBS, and the relationship between psychological factors and IBS were analyzed.

RESULTS: The insomnia and non-insomnia groups differed significantly in their rating of abdominal pain/discomfort in terms of severity and duration (P < 0.05), but there was no difference in attack frequency between the two groups. The incidence of somatic symptoms, scores of SAS and SDS, and scores of SAS' and SDS' (sleep-related entries were removed) were all significantly higher in the insomnia group than in the non-insomnia group (all P < 0.01). Severity, attack frequency and duration of abdominal pain/discomfort were all positively correlated with SAS and SDS scores (all P < 0.05).

CONCLUSION: Insomnia and insomnia-related psychological factors (anxiety, depression) can aggravate the symptoms of female patients with IBS.

A new class of analgesic agents toward prostacyclin receptor inhibition: Synthesis, biological studies and QSAR analysis of 1-hydroxyl-2-substituted phenyl-4,4,5,5-tetramethylimidazolines

By studying the structural similarity of analgesic imidazolines and 2-phenylnitronyl nitroxides, 20 1-hydroxyl-2-substituted phenyl-4,4,5,5-tetramethylimidazolines (2a-t) were newly synthesized as selective antagonists of prostacyclin receptor (IP receptor). In the in vivo tail-flick assay, 2a-t (dose, 0.13 mmol/kg) receiving mice showed increased pain thresholds ranging from 20.52+/-7.25% to 90.94+/-11.97%, which were significantly higher than that ranged from 12.27+/-9.56% to 17.71+/-7.00% shown by normal saline (NS) receiving mice. In the in vivo tail bleeding assay, 2a-t (dose, 1.30 mmol/kg) receiving mice gave a bleeding time ranging from 116.3+/-8.0 s to 119.6+/-7.1 s, and NS receiving mice gave a bleeding time ranging from 116.7+/-7.5s to 119.1+/-8.7s, which were at a substantially equal level. These observations imply that no bleeding risk occurred even when 10-fold dose of analgesic assay was used. In the in vitro vasorelaxation assay, it was found that when the aortic strip contracted by noradrenaline (NE, final concentration, 10(-7) M) was treated with the solution of 2a-t in NS (final concentration, 5 x 10(-3) M) only lower percentage inhibitions ranged from 6.63+/-2.72% to 46.28+/-2.63% were recorded. Relatively higher concentration of 2a-t (5 x 10(-3) M) and relatively lower percentage inhibitions (13 of 20 less than 23.27+/-3.47%) suggest that 2a-t exhibit few vasodilation activity. To shed some light on the potential analgesic mechanisms of 2a-t, moreover, a QSAR analysis was carried out by using the multiple linear regression method. Taken altogether, the current study confirms that as selective antagonist of IP receptor 1-hydroxyl-2-substituted phenyl-4,4,5,5-tetramethylimidazoline may be a promising lead compound of analgesic agent without cardiovascular and bleeding side effects.

Effect of stem cell factor on colon interstitial cells of Cajal in murine with diabetes mellitus

AIM: To investigated whether exogenous stem cell factor (SCF) can improve the diabetes-associated depletion of interstitial cells of Cajal (ICC) in mice with diabetes mellitus (DM).

METHODS: DM mice were intraperitoneally injected with streptozocin (STZ) to induce an experimental model. Male C57/BL6 mice were randomly divided into control group, DM group and DM + SCF group. The mice in DM + SCF group were given exogenous SCF (0.2 µg/kg per day, ip) for 6 wk, and the mice in control group and DM group were given the same amount of phosphate buffer (pH = 7.4). All the mice were sacrificed after 6 wk. ICC changes in the distal colon were assessed by immunohistochemistry, transmission electron microscopy and Western blot, and SCF expression in the distal colon was analyzed by Western blot.

RESULTS: The expression of SCF in the distal colon was significantly reduced in DM group as compared with that in the control group (178.97 ± 13.51 vs 200.25 ± 16.48, P < 0.05), accompanied with the depletion (72 ± 10 vs 102 ± 12, P < 0.05) and microscopic lesions of ICC in the distal colon. The expression of SCF in the distal colon was increased in DM + SCF group (210.14 ± 11.8, P < 0.05), along with the dramatic improvement of ICC quantity (87 ± 10, P < 0.05) and ultrastructure in the distal colon as compared with those in DM group.

CONCLUSION: Exogenous SCF may improve the DM-associated depletion of colon ICC.

An improved prediction of catalytic residues in enzyme structures

The protein databases contain a huge number of function unknown proteins, including many proteins with newly determined 3D structures resulted from the Structural Genomics Projects. To accelerate experiment-based assignment of function, de novo prediction of protein functional sites, like active sites in enzymes, becomes increasingly important. Here, we attempted to improve the prediction of catalytic residues in enzyme structures by seeking and refining different encodings (i.e. residue properties) as well as employing new machine learning algorithms. In particular, considering that catalytic residues can often reveal specific network centrality when representing enzyme structure as a residue contact network, the corresponding measurement (i.e. closeness centrality) was used as one of the most important encodings in our new predictor. Meanwhile, a genetic algorithm integrated neural network (GANN) was also employed. Thanks to the above strategies, our GANN predictor demonstrated a high accuracy of 91.2% in the prediction of catalytic residues based on balanced datasets (i.e. the 1:1 ratio of catalytic to non-catalytic residues). When the GANN method was optimally applied to real enzyme structures, 73.9% of the tested structures had the active site correctly located. Compared with two existing methods, the proposed GANN method also demonstrated a better performance.

N-[2-(5,5-Dimethyl-1,3-dioxane-2-yl)ethyl]amino acids: Their synthesis, anti-inflammatory evaluation and QSAR analysis

Developing novel anti-inflammatory drugs is increasingly important in modern pharmaceutical industry. In this work, the reactions of both amino acids and their methylesters with 3-(5,5-dimethyl-1,3-dioxane-2-yl)propanal (2) were performed to either directly provide the goal products N-[2-(5,5-dimethyl-1,3-dioxane-2-yl)ethyl]amino acids (4a-s) in 9-65% yields or provide the intermediates N-[2-(5,5-dimethyl-1,3-dioxane-2-yl)ethyl]amino acid methylesters (3a-s) in 78-87% yields. The saponification of 3a-s provided 4a-s in 80-89% yields. Using a xylene-induced ear edema model, the anti-inflammatory activities of these newly synthesized anti-inflammatory agents were evaluated. The results indicated that comparing to the vehicle control 17 out of 4a-s significantly inhibited the development of inflammation in mice (p<0.01). In particular, eight out of 4a-s exhibited an even higher anti-inflammatory activity than the standard reference drug aspirin (p<0.05-0.01). A QSAR analysis was performed by use of the molecular descriptors generated from e-dragon software. The predictive accuracy of the established QSAR model implies that it may be promising for screening the new derivatives of 2-position amino acid substituted 1,3-dioxanes as potential anti-inflammatory agents.

GANNPhos: a new phosphorylation site predictor based on a genetic algorithm integrated neural network

With the advance of modern molecular biology it has become increasingly clear that few cellular processes are unaffected by protein phosphorylation. Therefore, computational identification of phosphorylation sites is very helpful to accelerate the functional understanding of huge available protein sequences obtained from genomic and proteomic studies. Using a genetic algorithm integrated neural network (GANN), a new bioinformatics method named GANNPhos has been developed to predict phosphorylation sites in proteins. Aided by a genetic algorithm to optimize the weight values within the network, GANNPhos has demonstrated a high accuracy of 81.1, 76.7 and 73.3% in predicting phosphorylated S, T and Y sites, respectively. When benchmarked against Back-Propagation neural network and Support Vector Machine algorithms, GANNPhos gives better performance, suggesting the GANN program can be used for other prediction tasks in the field of protein bioinformatics.

Studies on logP, retention time and QSAR of 2-substituted phenylnitronyl nitroxides as free radical scavengers

As reported in our previous paper [Y. Wu, L. Bi, W. Bi, Z. Li, M. Zhao, C. Wang, J. Ju, S. Peng, Bioorg. Med. Chem. 14 (2006) 5711-5720.], a series of novel 2-substituted nitronyl nitroxides were synthesized and characterized to show enhanced free radical scavenger properties. Here, the logP values and retention time (alternatively represented as logK) of these 20 compounds were determined by the shake-flask method and HPLC analysis, respectively. We found that the prediction of logP directly from the measured logK value can result in a high accuracy, thus the determination of time-consuming logP can be replaced by the simple HPLC analysis. Using the conventional Hansch method, the QSAR equations of these nitronyl nitroxides were established to predict their capability of trapping free radicals such as *NO, *H(2)O(2) and *OH. Although the overall predictive accuracy is reasonable, it was found that the logP values for the compounds are not significantly related to their capability of trapping free radicals. Moreover, an improved QSAR analysis was performed by choosing new molecular descriptors generated from e-dragon server. The increased predictive accuracy suggests that these new QSAR models have practical application in screening new potential scavengers from the derivatives of 2-substituted phenylnitronyl nitroxides.

Genome-wide analysis of enzyme structure-function combination across three domains of life

To investigate diverse enzyme structure-function combination (SFC) types in different species, 34 different genome sequences were annotated using the protein catalytic domain database SCOPEC (http://www.enzome.com/enzome/), in which both the structure and function for each entry are known. Annotated enzymes with catalytic domains from the same SCOP superfamily are considered to have an identical structure. Annotated enzymes sharing the identical three-digit EC number are considered to have the same enzymatic function. Results reveal that the different SFC types for enzymes identified in archaea, bacteria and eukaryota are 137, 300 and 313, respectively. About 80% of the SFCs identified in archaea can be consistently found in bacteria and eukaryota species, whereas 28% and 35% combination types in bacteria and eukaryota respectively are unique to their corresponding groups. The number of functions per structure and the number of structures per function for the annotated sequences were measured in different species. Furthermore, a new concept was proposed to represent enzymatic structures as a functional similarity network. Thus, the current study will be helpful to enhance the global view on the evolution of enzymatic structure and function.

Novel 1-oxyl-2-substitutedphenyl-4,4,5,5-tetramethylimidazolines: Synthesis, selectively analgesic action, and QSAR analysis

Based on the knowledge that imidazoline can result in analgesic action due to its selective binding with the prostacyclin receptor, 20 1-oxyl-2-substitutedphenyl-4,4,5,5-tetramethylimidazolines (3a-t) were prepared in moderate yields. At 0.13 mmol/kg dose, their in vivo analgesic activities were evaluated after the mice were administered at 30, 60, 90, and 150 min. Compared with the pain threshold (12.27+/-9.56-17.71+/-7.00%) of normal saline (NS) receiving mice, the pain threshold (23.42+/-8.14% to 102.58+/-10.66%) of 3a-t receiving mice increases significantly. Considering a prostacyclin receptor targeting analgesic agent usually had bleeding action and to appraise the bleeding risk, the in vivo tail bleeding time of 1.30 mmol/kg 3a-t receiving mice was found to be ranged from 116.3+/-8.2s to 120.3+/-9.2s, which was substantially equal to that (117.8+/-8.4s to 119.0+/-8.6s) of NS receiving mice. Based on the possibility of imidazoline acting as vasodilator, the in vitro vasorelaxations of 3a-t were tested using the rat aortic strip model. When the aortic strip contracted by noradrenaline (NE, final concentration 10(-7)mol/l) was treated with 3a-t (final concentration 5 x 10(-4)mol/l), only lower percentage inhibitions (6.55+/-5.70-37.40+/-4.07%) were recorded, implying that the vasorelaxation of 3a-t was neglectable. By selecting appropriate molecular descriptors generated from e-dragon server, the QSAR model of the analgesic activities of 3a-t was constructed using the multiple linear regression method. The established QSAR model showed reasonable accuracy and thus it is promising to be used for screening new 1-oxyl-2-substitutedphenyl-4,4,5,5-tetramethylimidazoline derivatives as analgesic agents.

Studies of five microelement contents in human serum, hair, and fingernails correlated with aged hypertension and coronary heart disease

Using atomic absorption spectrometry (AAS), five microelements in human serum, hair, and fingernails of aged hypertension, coronary heart disease (diseased group) and aged health control (healthy group) were detected. Results of the t-test are as follows: The iron, zinc, and cadmium contents and Zn/Cu (mol/mol) ratio of the diseased group were significantly higher than that of the healthy group in serum (p<0.01, p<0.05, p<0.01, and p<0.05, respectively); the chromium contents in the serum, hair, and fingernails (p<0.05, p<0.01, and p<0.05, respectively); the iron and zinc contents in the hair and fingernails (p<0.01, p<0.001, p<0.05, and p<0.01 respectively) and Zn/Cu ratio in the hair (p<0.01) of the diseased group were significantly lower than that of the healthy group.

Effects of the menstrual cycle on respiratory muscle function

To investigate the effect of the menstrual cycle on respiratory muscle function, respiratory muscle and pulmonary functions were measured and compared in the midfollicular phase and in the midluteal phase of the menstrual cycle in 30 healthy adult women. Respiratory muscle strength was indicated by maximal static inspiratory and expiratory pressures. Inspiratory muscle endurance was determined by the product of pressure load and the sustained time, i.e., pressure-time index, while the subject breathed against an inspiratory pressure load on a modified Nickerson-Keens device. The results showed that the inspiratory muscle endurance was greater in the midluteal phase than in the follicular phase (815 +/- 43 versus 649 +/- 62 cmH2O.min, respectively), whereas the respiratory muscle strength and pulmonary function were unchanged. We conclude that inspiratory muscle endurance is affected by the menstrual cycle, i.e., higher in the midluteal phase and lower in the midfollicular phase.

Sleep loss impairs inspiratory muscle endurance

Sleep loss is common in patients with respiratory disorders. To determine whether sleep loss affects respiratory muscle function, we compared respiratory muscle and pulmonary functions after normal sleep with those measured after a 30-h sleepless period in 30 normal male subjects. The respiratory muscle strength was estimated by the maximal static inspiratory and expiratory pressures. Inspiratory muscle endurance was determined by the product of pressure load and the sustained time, i.e., pressure-time index, while the subject breathed against an inspiratory pressure load on a modified Nickerson-Keens device. We found that inspiratory muscle endurance was decremented from 871 +/- 61 to 638 +/- 69 cm H2O.min after sleep deprivation. Twelve-second maximal voluntary ventilation was also significantly reduced after sleep loss. Nevertheless, the respiratory muscle strength, FEV1, and FVC were unaltered. We therefore conclude that inspiratory muscle endurance may deteriorate after a 30-h sleep loss.

Effects of acute exercise on bleeding time, bleeding amount and blood cell counts: a comparative study

Twenty-five men and 26 women were studied to investigate the effects of acute strenuous exercise on hemostasis after obtaining their informed consent. After familiarization, they performed exercise on a bicycle ergometer at 75% of their predetermined maximal workload until exhaustion. Bleeding time, measured by the Simplate method, and venous blood cell counts of platelets (Plt), erythrocytes (RBC), leukocytes (WBC) were determined at rest and immediately after exercise. We found that bleeding time of Chinese in our study was longer than those of the westerners in other studies and that bleeding time was significantly shortened after exercise from 8.3 +/- .7 to 6.5 +/- .5 min in men and from 11.4 +/- .9 to 8.6 +/- .8 min in women (p less than 0.001). In men, but not in women, acute exercise also augmented the initial bleeding rate and bleeding amount from standard incisions. We also observed that RBC, WBC and Plt counts were greatly increased. The increased percentages for RBC, WBC and Plt in men were 7 +/- 1%, 59 +/- 7%, 16 +/- 3%, and those in women were 5 +/- 1%, 42 +/- 6% and 17 +/- 2% respectively.