A retrospective study on the socio-demographic factors and clinical parameters of dengue disease and their effects on the clinical course and recovery of the patients in a tertiary care hospital of Bangladesh

Dengue, a mosquito transmitted febrile viral disease, is a serious public health concern in Bangladesh. Despite significant number of incidences and reported deaths each year, there are inadequate number of studies relating the temporal trends of the clinical parameters as well as socio-demographic factors with the clinical course of the disease. Therefore, this study aims to associate the clinical parameters, demographic and behavioral factors of the dengue patients admitted in a tertiary care hospital in Dhaka, Bangladesh during the 2019 outbreak of dengue with the clinical course of the disease. Data were collected from the 336 confirmed dengue in-patients and analyzed using SPSS 26.0 software. Majority of the patients were male (2.2 times higher than female) who required longer time to recover compared to females (p < 0.01), urban resident (54.35%) and belonged to the age group of 18–40 years (73.33%). Dengue fever (90.77%) and dengue hemorrhagic fever (5.95%) were reported in most of the dengue patients while fever (98%) was the most frequently observed symptom. A significantly positive association was found between patient’s age and number of manifested symptoms (p = 0.013). Average duration of stay in the hospital was 4.9 days (SD = 1.652) and patient’s recovery time was positively correlated with delayed hospitalization (p < 0.01). Additionally, recovery time was negatively correlated with initial blood pressure (both systolic (p = 0.001, and diastolic (p = 0.023)) and platelet count (p = 0.003) of the patients recorded on the first day of hospitalization. Finally, a statistical model was developed which predicted that, hospital stay could be positively associated with an increasing trend of temperature, systolic blood pressure and reduced platelets count. Findings of this study may be beneficial to better understand the clinical course of the disease, identify the potential risk factors and ensure improved patient management during future dengue outbreaks.     

Pentapeptide amides interfere with the aggregation of beta-amyloid peptide of Alzheimer's disease

Amyloid peptides (Abeta) play a central role in the pathogenesis of Alzheimer's disease (AD). The aggregation of Abeta molecules leads to fibril and plaque formation. Fibrillogenesis is at the same time a marker and an indirect cause of AD. Inhibition of the aggregation of Abeta could be a realistic therapy for the illness. Beta sheet breakers (BSBs) are one type of fibrillogenesis inhibitors. The first BSB peptides were designed by Tjernberg et al. (1996) and Soto et al. (1998). These pentapeptides have proved their efficiency in vitro and in vivo. In the present study, the effects of two pentapeptide amides are reported. These compounds were designed by using the C-terminal sequence of the amyloid peptide as a template. Biological assays were applied to demonstrate efficiency. Modes of action were studied by FT-IR spectroscopy and molecular modeling methods.     

Detection of Streptococcus pneumoniae from Different Types of Nasopharyngeal Swabs in Children

Background

A better understanding of the epidemiology of nasopharyngeal carriage of Streptococcus pneumoniae is important to assess the impact of vaccination and the pathogenesis of pneumococcal disease. We compared the recovery of S. pneumoniae from nylon flocked, Dacron and rayon swabs.

Methods

The recovery of S. pneumoniae from mocked specimens using flocked, Dacron and rayon swabs were compared by culture. The yield from paired nasopharyngeal (NP) samples obtained from healthy children sampled with flocked and Dacron swabs was also determined using culture and lytA-targeted real-time polymerase chain reaction (qPCR).

Results

Using mock specimen, the percentage recovery of S. pneumoniae ATCC 49619 (serotype 19F) strain from the flocked swabs was 100%, while it was 41% from Dacron swabs and 7% from rayon swabs. Similar results were observed for S. pneumoniae serotypes 1 and 5. S. pneumoniae was cultured from 18 of 42 (43%) paired NP samples from the healthy children (median age 8 [interquartile range (IQR) 5–16] months). The median number of colony-forming units (CFU) recovered from flocked swabs was two-fold higher (8.8×10⁴ CFU/mL [IQR, 2.0×10² – 4.0×10⁵ CFU/mL]) than Dacron swabs (3.7×10⁴ CFU/mL [IQR, 4.0×10²–3.2×10⁵ CFU/mL], p = 0.17). Using lytA-targeted qPCR from paired NP samples, the median copy number of S. pneumoniae detected from flocked swabs was significantly higher than from Dacron swabs (3.0×10⁵ genome copies/mL [IQR, 1.3×10²−1.8×10⁶] vs. 9.3×10⁴ genome copies/mL [IQR, 7.0×10¹−1.1×10⁶]; p = 0.005).

Conclusion

Flocked swabs released more S. pneumoniae compared to both Dacron and rayon swabs from mock specimens. Similarly, higher bacterial loads were detected by qPCR from flocked swabs compared with Dacron swabs from healthy children.     

Risk Factors for Multidrug-Resistant Tuberculosis among Patients with Pulmonary Tuberculosis at the Central Chest Institute of Thailand

There are limited data available on the risk factors for multidrug-resistant tuberculosis (MDR-TB). Therefore, we here conducted a retrospective matched case−control study among adults with pulmonary TB who received treatment at the Central Chest Institute of Thailand (CCIT) between January 2007 and December 2013, in order to determine the risk factors associated with MDR-TB among patients with pulmonary TB. We identified 145 patients with pulmonary MDR-TB (cases) and 145 patients with drug-sensitive pulmonary TB (controls). Multivariate analysis identified the independent risk factors for MDR-TB as follows: (1) ≥ 2 episodes of prior pulmonary TB (odds ratio [OR] 39.72, 95% confidence interval (95% CI) 7.86−200.66), (2) duration of illness > 60 days (OR 3.08, 95% CI 1.52−6.22), (3) sputum acid fast bacilli smear 3+ (OR 13.09, 95% CI 4.64−36.91), (4) presence of lung cavities (OR 3.82, 95% CI 1.89−7.73), and (5) presence of pleural effusion (OR 2.75, 95% CI 1.06−7.16). Prior pulmonary TB management with a non-category I regimen (P = 0.012) and having treatment failure or default as treatment outcomes (P = 0.036) were observed in a higher proportion among patients with MDR-TB. Particular characteristics of lung cavities, including the maximum diameter ≥ 30 mm (P < 0.001), the number of cavities ≥ 3 (P = 0.001), bilateral involvement (P < 0.001), and ≥ 2 lung zones involved (P = 0.001) were more commonly observed in patients with MDR-TB. In conclusion, these clinical factors and chest radiographic findings associated with MDR-TB among patients with pulmonary TB may help physicians to provide proper management of cases for prevention of the development and spread of MDR-TB in future.     

Mild hypothermia protects against postischemic hepatic endothelial injury and decreases the formation of reactive oxygen species

The ability of mild hypothermia (MH; 34 degrees C) to protect against postischemic endothelial injury and decrease reactive oxygen species' (ROS) formation was studied using lucigenin and luminol enhanced chemiluminescence (CL). Lucigenin CL is largely specific for superoxide, while luminol reacts with many ROS. Isolated rat livers perfused under constant flow in a non-recirculating system were exposed to 2.5 h of ischemia after 0.5 h perfusion with Krebs-Henseleit buffer at either normothermia (38 degrees C) or mild hypothermia (34 degrees C) (n = 5, all groups). CL (cps), vascular resistance (Woods units), O2 consumption, and potassium efflux were measured at the end of perfusion, and at 0 min reperfusion, and every 30 min during reperfusion. For both the lucigenin and luminol groups, CL and vascular resistance increased significantly (repeat measures ANOVA, P <0.05) for normothermia (NT, 38 degrees C) but not mild hypothermia. Potassium efflux did not change significantly for the mild hypothermia groups. In the luminol enhanced group, oxygen consumption was greater in the mildly hypothermic group at 1 h and 1.5 h of reperfusion. Mild hypothermia decreased postischemic ROS production. Increased vascular resistance in the normothermia group may indicate an endothelial injury. Mild hypothermia appears to protect against this injury.     

Antifouling properties of zinc oxide nanorod coatings

In laboratory experiments, the antifouling (AF) properties of zinc oxide (ZnO) nanorod coatings were investigated using the marine bacterium Acinetobacter sp. AZ4C, larvae of the bryozoan Bugula neritina and the microalga Tetraselmis sp. ZnO nanorod coatings were fabricated on microscope glass substrata by a simple hydrothermal technique using two different molar concentrations (5 and 10?mM) of zinc precursors. These coatings were tested for 5?h under artificial sunlight (1060?W?m^?2 or 530?W?m^?2) and in the dark (no irradiation). In the presence of light, both the ZnO nanorod coatings significantly reduced the density of Acinetobacter sp. AZ4C and Tetraselmis sp. in comparison to the control (microscope glass substratum without a ZnO coating). High mortality and low settlement of B. neritina larvae was observed on ZnO nanorod coatings subjected to light irradiation. In darkness, neither mortality nor enhanced settlement of larvae was observed. Larvae of B. neritina were not affected by Zn²⁺ ions. The AF effect of the ZnO nanorod coatings was thus attributed to the reactive oxygen species (ROS) produced by photocatalysis. It was concluded that ZnO nanorod coatings effectively prevented marine micro and macrofouling in static conditions.     

Banana Rhizodeposition: Characterization of Root Border Cell Production and Effects on Chemotaxis and Motility of the Parasitic Nematode Radopholus similis

Rhizodeposition was collected from root tips of banana (Musa acuminata). Two varieties, Grande naine and Yangambi km5, susceptible and resistant towards the burrowing nematode Radopholus similis, respectively, were examined for root border cell production under in vitro and in soil growing conditions. Two types of cells were observed in rhizodeposition: spherical cells containing large amyloplasts, called statocytes (8% of total), and long ellipsoidal border cells (92%). Border cell production was high, related to root length and not different between the two cultivars. Rhizodeposition from plants grown in soil contained similar amounts of border cells, but viability was lower than in in vitro grown plants. Chemotaxis and motility assays were performed to test the effects of banana roots, roots without rhizodeposition, rhizodeposition, exudates and border cells on the behaviour of R. similis. Roots of both the susceptible and resistant variety attracted R. similis, but only in the presence of rhizodeposition. Isolated rhizodeposition of Yangambi km5 also attracted nematodes. Border cells and exudates did not affect nematode chemotaxis. Roots of both varieties induced quiescence in R. similis in the chemotaxis assay. Thirty to fifty percent of the nematodes became temporary quiescent in the motility assay with rhizodeposition and exudates. The effect lasted for 24 h for Grande naine and up to 3 days for Yangambi km5. Rhizodeposition collected from plants grown in soil affected neither R. similis chemotaxis nor motility. Overall, there were no indications that rhizodeposition is involved in preformed resistance against R. similis in Yangambi km5.     

Effects of interaction between65Zn,cadmium, and copper in rats

Distribution and retention of zinc in the presence of cadmium and copper was studied in rats exposed repeatedly to these metals. The experiment was performed on white rats of the Wistar strain. The animals were divided into four groups/five rats each: 1)⁶⁵ZnCl₂; 2)⁶⁵ZnCl₂+CdCl₂; 3)⁶⁵ZnCl₂+CuCl₂; and 4) control group. Rats were administered sc every other day for two weeks:⁶⁵ZnCl₂−5 mg Zn/kg; CdCl₂−0,3 Cd/kg; and CuCl₂−2 mg Cu/kg. The zinc content was measured in rat tissues by γ-counting. Effect of Cd and Cu on subcellular distribution of zinc in the kidney and liver and on the level of metallothionein were also examined. Whole body retention of zinc under the influence of cadmium was lower than that observed in animals treated with zinc alone. However, copper increased twofold the whole body retention of zinc. Cadmium elevated the accumulation of zinc only in the kidneys nuclear fraction and liver soluble fraction. In the kidneys and liver, copper elevated the accumulation of zinc, in the nuclear, mitochondrial, and soluble fractions. The level of metallothionein-like proteins (MT) in the kidneys after a combined supply of zinc and copper was significantly increased with respect to the group of animals treated with zinc alone. These results indicated complex interactions between cadmium, copper, and zinc that can affect the metabolism of each of the metals.