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101.

Background

Dendritic cells (DCs) promote pathogen recognition, uptake and presentation of antigen through DC-specific intercellular adhesion molecule 3-grabbing non-integrin (DC-SIGN) and toll-like receptors (TLRs).

Aims and Objectives

We aimed to study temporal changes in DCs, TLRs and DC-SIGN during acute viral hepatitis B (AVHB) infection and compare them to chronic (CHB) and to investigate the earliest time point of activated pathogen recognition receptors in hepatitis B viral infection.

Methods

We measured the frequencies of circulating myeloid (mDC) and plasmacytoid (pDC) dendritic cells and IFN-α production along with the expression of DC-SIGN and Toll Like Receptors (TLR's) in HBV patients at different time points. Also investigated in healthy volunteers, the dynamic changes in TLRs expression after receiving hepatitis B vaccine.

Results

On follow-up of AVHB patients, we found the mDC population was significantly higher at week 4 and 6 (p < 0.02, 0.01), whereas the pDC population was unchanged at week 6 compared with week 0. Whereas frequencies of mDCs and pDCs were found to be elevated in AVHB and CHB patients than HC (p < 0.00 and 0.01, respectively) but was comparable among AVHB vs CHB. The DCs in CHB patients were functionally impaired with significantly low IFN-α production and low DCSIGN expression (p < 0.04 and 0.00, respectively). Even after stimulation by TLR agonists, no change was found in IFN-α production in CHB patients. MyD88 and IL-6, IFN-α mRNA levels were also found down-regulated. Interestingly, on follow-up after HBV vaccine, TLRs expression was found high at day 3 after vaccination.

Discussion

The initial events of immune activation might be responsible for modulating immune response. These novel observations would pave the way for the development of antiviral strategies for chronic HBV infection.
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102.
103.
A series of novel d-glucose-derived 1,2,3-triazoles have been synthesized in excellent yields via Cu(I)-catalyzed 1,3-dipolar cycloaddition by using methyl α-d-glucopyranoside as starting material. All the new compounds were confirmed by 1H NMR, 13C NMR, IR, MS, and HRMS spectra, and their antimicrobial activities were screened against Gram-Positive, Gram-Negative bacteria, and fungi. Bioactive assay manifested that some of the synthesized glucose-derived 1,2,3-triazoles exhibited good antibacterial and antifungal activities. Notably, compound 5k gave the most potent efficiency with MIC50 value of 6 µM against Candida albicans, which was nine-fold more active than the reference drug Fluconazole. It also exhibited good antibacterial activity against Escherichia coli with the MIC50 value of 10.8 µM compared to Chloramphenicol while the corresponding hydrochloride 4k revealed remarkable inhibitory against Bacillus subtilis with an MIC50 value of 11 µM.  相似文献   
104.
105.
Background:Chronic kidney disease (CKD)-associated pruritus (CKD-aP) contributes to poor quality of life, including reduced sleep quality and poor sleep quality is a source of patient stress and is linked to lower health-related quality of life. This study aimed to investigate the effectiveness of zolpidem 10 mg and acupressure therapy on foot acupoints to improve the sleep quality and overall quality of life among hemodialysis patients suffering from CKD-aP.Method:A multicenter, prospective, randomized, parallel-design, open label interventional study to estimate the effectiveness of zolpidem (10 mg) oral tablets versus acupressure on sleep quality and quality of life in patients with CKD-aP on hemodialysis. A total of 58 hemodialysis patients having sleep disturbance due to CKD-aP completed the entire 8-week follow-up. The patients were divided into a control (acupressure) group of 28 patients and an intervention (zolpidem) group of 30 patients.Results:A total of 58 patients having CKD-aP and sleep disturbance were recruited. In the control group there was a reduction in the PSQI score with a mean ± SD from 12.28 ± 3.59 to 9.25 ± 3.99, while in the intervention group the reduction in PSQI score with a mean ± SD was from 14.73 ± 4.14 to 10.03 ± 4.04 from baseline to endpoint. However, the EQ5D index score and EQ-visual analogue scale (VAS) at baseline for the control group with a mean ± SD was 0.49 ± 0.30 and 50.17 ± 8.65, respectively, while for the intervention group the values were 0.62 ± 0.26 and 47.17 ± 5.82, respectively. The mean EQ5D index score in the control group improved from 0.49 ± 0.30 to 0.53 ± 0.30, but in the intervention group there was no statistical improvement in mean EQ5D index score from 0.62 ± 0.26 to 0.62 ± 0.27 from baseline to week 8. The EQ 5D improved in both groups and the EQ-VAS score was 2.67 points higher at week 8 as compared to baseline in the control group, while in the intervention group the score was 3.33 points higher at week 8 as compared to baseline. Comparing with baseline, the PSQI scores were significantly reduced after week 4 and week 8 (P =  < .001). Furthermore, at the end of the study, the PSQI scores were significantly higher in the control as compared to the intervention group (P = .012).Conclusion:An improvement in sleep quality and quality of life among CKD-aP patients on hemodialysis has been observed in both the control and intervention groups. Zolpidem and acupressure safety profiling showed no severe adverse effect other that drowsiness, nausea and daytime sleeping already reported in literature of zolpidem.  相似文献   
106.
107.
INTRODUCTION: Human papillomavirus (HPV) is recognized as a major causative agent for cervical carcinomas. Based on their oncogenic potential, HPV subtypes have been divided into high- and low-risk. In Pakistan, screening for HPV in female patients is not commonly practiced, and as a consequence, the degree of HPV prevalence and its correlation with cervical cancer is unknown. OBJECTIVE: In this study, we have attempted to estimate the prevalence of HPV infection, and also the HPV subtype profile, among Pakistani women with cervical cancer from varied geographical, racial, and social backgrounds within Pakistan. METHODOLOGY: Women visiting two tertiary care hospitals in Karachi, diagnosed with carcinoma of the cervix within the past 15 years, were analyzed for HPV subtypes in their cancer specimens. Retrospectively, 60 paraffin-embedded cervical cancer biopsies were examined for the presence of HPV DNA. After DNA extraction from these samples, polymerase chain reaction (PCR) was used to amplify the HPV L1 gene using the consensus (general) primers, and primers specific for subtypes 16 and 18. RESULTS: Of the 60 samples analyzed, only one sample was HPV negative; the rest of the samples were positive for the presence of HPV. Of the 59 HPV positive samples, 56 showed the presence of HPV16 and one sample was positive for HPV18; HPV subtype could not be determined in two samples. CONCLUSION: Our results show a strong relationship between HPV infection and cervical cancer among Pakistani women. These results underscore the need to implement regular HPV screening for Pakistani women. An early diagnosis of HPV infection will allow better health management to reduce the risk of developing cervical cancer.  相似文献   
108.
3-nitropropionic acid (3-NPA) neurotoxicity and long-term effects of perinatal hypoxia were evaluated in 18 adult rats. Hypoxia-insulted (I) and noninsulted (NI) rats were delivered by cesarean section. Hypoxic insult was effected by submerging dissected uterine horns in warmed saline for 15 min. NI rats were delivered from the adjacent nonsubmerged horns. At postnatal day 90, I and NI rats were trained to perform tasks thought to measure behaviors dependent upon aspects of time estimation (TE), motivation, and learning. At 12 months of age, rats were injected i.p. with escalating doses of 3-NPA (5 mg/kg/day to a maximum of 30 mg/kg/day) immediately after each test session and sacrificed at the end of treatment. Additional male rats were used as untreated controls. Although 3-NPA produced a dose-dependent impairment of performance in each task, the effects were qualitatively similar for each group. A significant difference between I and NI rats was, however, observed in the TE task where NI rats completed less of the task at high doses of 3-NPA compared to I rats. Compared to untreated controls, dopamine concentrations were decreased in caudate nucleus of both I and NI rats after 3-NPA. Specific areas most frequently damaged included cerebral cortex, hippocampal subfield CA1, thalamus, caudate nucleus, and the cerebellum. Lesions usually were less extensive in the I rather than NI members of a littermate pair, suggesting a possible protective effect of perinatal hypoxia against subsequent 3-NPA neurotoxicity.  相似文献   
109.
The current study aims at the development of an electrochemical sensor based on a silver nanoparticle–reduced graphene oxide–polyaniline (AgNPs–rGO–PANI) nanocomposite for the sensitive and selective detection of hydrogen peroxide (H2O2). The nanocomposite was fabricated by simple in situ synthesis of PANI at the surface of rGO sheet which was followed by stirring with AEC biosynthesized AgNPs to form a nanocomposite. The AgNPs, GO, rGO, PANI, rGO–PANI, and AgNPs–rGO–PANI nanocomposite and their interaction were studied by UV-vis, FTIR, XRD, SEM, EDX and XPS analysis. AgNPs–rGO–PANI nanocomposite was loaded (0.5 mg cm−2) on a glassy carbon electrode (GCE) where the active surface area was maintained at 0.2 cm2 for investigation of the electrochemical properties. It was found that AgNPs–rGO–PANI–GCE had high sensitivity towards the reduction of H2O2 than AgNPs–rGO which occurred at −0.4 V vs. SCE due to the presence of PANI (AgNPs have direct electronic interaction with N atom of the PANI backbone) which enhanced the rate of transfer of electron during the electrochemical reduction of H2O2. The calibration plots of H2O2 electrochemical detection was established in the range of 0.01 μM to 1000 μM (R2 = 0.99) with a detection limit of 50 nM, the response time of about 5 s at a signal-to-noise ratio (S/N = 3). The sensitivity was calculated as 14.7 μA mM−1 cm−2 which indicated a significant potential as a non-enzymatic H2O2 sensor.

The current study aims at the development of an electrochemical sensor based on a silver nanoparticle–reduced graphene oxide–polyaniline (AgNPs–rGO–PANI) nanocomposite for the sensitive and selective detection of hydrogen peroxide (H2O2).  相似文献   
110.

Background

Cardiopulmonary resuscitation (CPR) is a key component of emergency care following cardiac arrest. A better understanding of factors that influence CPR outcomes and their prognostic implications would help guide care. A retrospective analysis of 800 adult patients that sustained an in- or out-of-hospital cardiac arrest and underwent CPR in the emergency department of a tertiary care facility in Karachi, Pakistan, between 2008 and 15 was conducted.

Methods

Patient demographics, clinical history, and CPR characteristics data were collected. Logistic regression model was applied to assess predictors of return of spontaneous circulation and survival to discharge. Analysis was conducted using SPSS v.21.0.

Results

Four hundred sixty-eight patients met the study’s inclusion criteria, and overall return of spontaneous circulation and survival to discharge were achieved in 128 (27.4%) and 35 (7.5%) patients respectively. Mean age of patients sustaining return of spontaneous circulation was 52 years and that of survival to discharge was 49 years. The independent predictors of return of spontaneous circulation included age ≤?49 years, witnessed arrest, ≤?30 min interval between collapse-to-start, and 1–4 shocks given during CPR (aOR (95% CI) 2.2 (1.3–3.6), 1.9 (1.0–3.7), 14.6 (4.9–43.4), and 3.0 (1.4–6.4) respectively), whereas, age ≤?52 years, bystander resuscitation, and initial rhythm documented (pulseless electrical activity and ventricular fibrillation) were independent predictors of survival to discharge (aOR (95% CI) 2.5 (0.9–6.5), 1.4 (0.5–3.8), 5.3 (1.5–18.4), and 3.1 (1.0–10.2) respectively).

Conclusion

Our study notes that while the majority of arrests occur out of the hospital, only a small proportion of those arrests receive on-site CPR, which is a key contributor to unfavorable outcomes in this group. It is recommended that effective pre-hospital emergency care systems be established in developing countries which could potentially improve post-arrest outcomes. Younger patients, CPR initiation soon after arrest, presenting rhythm of pulseless ventricular tachycardia and ventricular fibrillation, and those requiring up to four shocks to revive are more likely to achieve favorable outcomes.
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