Assessment of interleukin 1 receptor antagonist (IL-1RA) levels in children with and without community acquired pneumonia: a hospital based case-control study

The primary objective was to compare serum interleukin-1 receptor antagonist (IL-1RA) levels in cases of community acquired pneumonia (CAP) and healthy age-gender-matched controls. The secondary objective was to compare serum IL-1RA levels in cases which were positive or negative for Streptococcus pneumoniae in the blood by real-time-polymerase chain reaction (RT-PCR). Hospitalized children with World Health Organization defined CAP, aged 2-59 months, were included as cases. Healthy controls were recruited from the immunization clinic of the hospital. Enzyme-linked immunosorbent assay (ELISA) test was used to detect serum IL-1RA levels. Identification of S.pneumoniae in blood was done by RT-PCR. From October 2019 to October 2021, 330 cases (123, 37.27% female) and 330 controls (151, 45.75% females) were recruited. Mean serum IL-1RA levels (ng/ml) were 1.36 ± 0.95 in cases and 0.25 ± 0.25 in controls (p < 0.001). Within cases, serum IL-1RA levels were significantly higher in those whose RT-PCR was positive for S.pneumoniae. Thus serum IL-1RA levels may be evaluated as a surrogate marker of S.pneumoniae in future studies.

Detection of Overexpression of Efflux Pump Expression in Fluoroquinolone-Resistant Pseudomonas aeruginosa Isolates

Context:

Fluoroquinolones are the most effective antibiotics against Pseudomonas aeruginosa; many strains, however, have shown resistance due to mutations in DNA gyrase, topoisomerase IV, or in the efflux pumps. Little is known about P. aeruginosa efflux pump resistance mechanisms in the Kingdom of Bahrain.

Aim:

The aim was to study efflux pump-mediated fluoroquinolone resistance among P. aeruginosa isolates using phenotypic (E-test and agar dilution) and genotypic (real-time-polymerase chain reaction [RT-PCR]) methods.

Materials and Methods:

Fifty ciprofloxacin-resistant P. aeruginosa isolates were included in this study. Genus and species of P. aeruginosa were confirmed by conventional PCR. The minimum inhibitory concentration (MIC) of ciprofloxacin with and without carbonyl cyanide 3-chlorophenylhydrazone (CCCP) was determined by E-test and agar dilution test. The overexpression of genes MexB, MexD, MexF, and MexY was measured by RT-PCR.

Results:

All isolates were confirmed as P. aeruginosa. Among the fifty isolates, four showed reduction in ciprofloxacin MIC after addition of CCCP. These four isolates showed upregulation of expression of at least one of the four genes by RT-PCR. The mean gene expression of MexB, MexD, MexF, and MexY increased by 1.6, 4.65, 3.4, and 3.68-fold, respectively.

Conclusion:

The results demonstrate the presence and type of efflux pump overexpression, mandating for large multicentric studies.

Modulation of Radiation-induced Base Excision Repair Pathway Gene Expression by Melatonin

Objective:

Approximately 70% of all cancer patients receive radiotherapy. Although radiotherapy is effective in killing cancer cells, it has adverse effects on normal cells as well. Melatonin (MLT) as a potent antioxidant and anti-inflammatory agent has been proposed to stimulate DNA repair capacity. We investigated the capability of MLT in the modification of radiation-induced DNA damage in rat peripheral blood cells.

Materials and Methods:

In this experimental study, male rats (n = 162) were divided into 27 groups (n = 6 in each group) including: irradiation only, vehicle only, vehicle with irradiation, 100 mg/kg MLT alone, 100 mg/kg MLT plus irradiation in 3 different time points, and control. Subsequently, they were irradiated with a single whole-body X-ray radiation dose of 2 and 8 Gy at a dose rate of 200 MU/min. Rats were given an intraperitoneal injection of MLT or the same volume of vehicle alone 1 h prior to irradiation. Blood samples were also taken 8, 24, and 48 h postirradiation, in order to measure the 8-oxoguanine glycosylase1 (Ogg1), Apex1, and Xrcc1 expression using quantitative real-time-polymerase chain reaction.

Results:

Exposing to the ionizing radiation resulted in downregulation of Ogg1, Apex1, and Xrcc1 gene expression. The most obvious suppression was observed in 8 h after exposure. Pretreatments with MLT were able to upregulate these genes when compared to the irradiation-only and vehicle plus irradiation groups (P < 0.05) in all time points.

Conclusion:

Our results suggested that MLT in mentioned dose may result in modulation of Ogg1, Apex1, and Xrcc1 gene expression in peripheral blood cells to reduce X-ray irradiation-induced DNA damage. Therefore, administration of MLT may increase the normal tissue tolerance to radiation through enhancing the cell DNA repair capacity. We believed that MLT could play a radiation toxicity reduction role in patients who have undergone radiation treatment as a part of cancer radiotherapy.

Half a decade of mini-pool nucleic acid testing: Cost-effective way for improving blood safety in India

BACKGROUND AND OBJECTIVES

It is well established that Nucleic acid testing (NAT) reduces window phase of transfusion transmissible infections (TTI) and helps improve blood safety. NAT testing can be done individually or in pools. The objectives of this study were to determine the utility, feasibility and cost effectiveness of an in-house minipool-NAT(MP-NAT).

MATERIALS AND METHODS

Blood donors were screened by history, tested by ELISA and sero-negative samples were subjected to an in-house NAT by using reverse transcriptase-polymerase chain reaction (RT-PCR). Testing was done in mini-pools of size eight (8). Positive pools were repeated with individual samples.

RESULTS

During the study period of Oct 2005-Sept 2010 (5 years) all blood donors (n=53729) were screened by ELISA. Of which 469 (0.87%) were positive for HIV-1, HBV or HCV. Sero-negative samples (n=53260) were screened by in-house MP-NAT. HIV-NAT yield was 1/53260 (n=1) and HBV NAT yield (n=2) was 1/26630.

CONCLUSION

NAT yield was lower than other India studies possibly due to the lower sero-reactivity amongst our donors. Nevertheless it intercepted 9 lives including the components prepared. The in-house assay met our objective of improving blood safety at nominal cost and showed that it is feasible to set up small molecular biology units in medium-large sized blood banks and deliver blood within 24-48 hours. The utility of NAT (NAT yield) will vary based on the donor population, the type of serological test used, the nature of kit employed and the sensitivity of NAT test used. The limitations of our in-house MP-NAT consisted of stringent sample preparation requirements, with labor and time involved. The benefits of our MP-NAT were that it acted as a second level of check for ELISA tests, was relatively inexpensive compared to ID-NAT and did not need sophisticated equipment.

Activation of Mas oncogene-related gene (Mrg) C receptors enhances morphine-induced analgesia through modulation of coupling of μ-opioid receptor to Gi-protein in rat spinal dorsal horn

Mas oncogene-related gene (Mrg) G protein-coupled receptors are exclusively expressed in small-sized neurons in trigeminal and dorsal root ganglia (DRG) in mammals. The present study investigated the effect of MrgC receptor activation on morphine analgesic potency and addressed its possible mechanisms. Intrathecal (i.t.) administration of the specific MrgC receptor agonist bovine adrenal medulla 8-22 (BAM8-22, 3 nmol) increased morphine-induced analgesia and shifted the morphine dose-response curve to the left in rats. Acute morphine (5 μg) reduced the coupling of μ-opioid receptors (MORs) to Gi-, but not Gs-, protein in the spinal dorsal horn. The i.t. BAM8-22 (3 nmol) prevented this change of G-protein repertoire while the inactive MrgC receptor agonist BAM8-18 (3 nmol, i.t.) failed to do so. A double labeling study showed the co-localization of MrgC and MORs in DRG neurons. The i.t. BAM8-22 also increased the coupling of MORs to Gi-protein and recruited Gi-protein from cytoplasm to the cell membrane in the spinal dorsal horn. Application of BAM8-22 (10nM) in the cultured ganglion explants for 30 min increased Gi-protein mRNA, but not Gs-protein mRNA. The present study demonstrated that acute administration of morphine inhibited the repertoire of MOR/Gi-protein coupling in the spinal dorsal horn in vivo. The findings highlight a novel mechanism by which the activation of MrgC receptors can modulate the coupling of MORs with Gi-protein to enhance morphine-induced analgesia. Hence, adjunct treatment of MrgC agonist BAM8-22 may be of therapeutic value to relieve pain.