Waheed Ullah

Chlorophyll derivatives can be an efficient weapon in the fight against dengue.

Dengue, a mosquito-borne viral infection, is one of the major public health concerns in the tropical and subtropical regions of the world. Approximately, 2.5 billion people across the world are at risk from dengue and 50 to 100 million new infections of dengue occur annually. There is yet no vaccine or medicine available against dengue, and treatment remains only supportive. Targeting its vector by a combination of biological and chemical approaches and management of breeding sites are currently the only existing approaches to control or eliminate dengue. Chlorophyll derivatives like chlorophyllin and pheophorbide have been reported as effective natural photosensitizers against larvae of several insects including flies. Chlorophyll derivatives were also reported effective against larval stages of freshwater snails as well as against certain parasites of fish. This article briefly discusses the possible application of chlorophyll derivatives in controlling dengue vectors and hence the disease itself. Chlorophyll derivatives can prove to be a good contributor in an integrated approach against dengue.

Gravitactic orientation of Euglena gracilis—a sensitive endpoint for ecotoxicological assessment of water pollutants

Pollution of aquatic environments with natural and anthropogenically produced substances is one of the major environmental problems of the world. In many countries the decreasing quantity of water coupled with its increasing usage in multiple sectors has adversely affected water quality and caused problems of water pollution. Polluted water has been a main cause of adverse effects on plants, animals and humans throughout the world. Physicochemical analysis of water, which is a common method used for quality assessment of water, alone may not be enough as it cannot evaluate the impact on living organisms. Therefore, bioassessment of water and wastewater quality is considered to be essential to reflect the ultimate effects on living organisms. Many organisms like bacteria, algae, fish, invertebrates and protozoan are used as bioassay organisms for assessment of water quality. This review article elucidates the use of Euglena gracilis, a freshwater motile flagellate of the phylum Euglenophyta, as a suitable organism in ecotoxicological studies with special emphasis on its gravitactic orientation as a sensitive end point in ecotoxicological assessment of water pollutants.

Expanding the clinical and genetic spectrum of G6PD deficiency: The occurrence of BCGitis and novel missense mutation

Glucose-6-phosphate dehydrogenase (G6PD) is a key enzyme in the pentose phosphate pathway that ensures sufficient production of coenzyme nicotinamide adenine dinucleotide phosphate (NADPH) by catalyzing the reduction of NADP+ to NADPH. Noteworthy, the latter mediates the production of reactive oxygen species (ROS) by phagocytic cells such as neutrophils and monocytes. Therefore, patients with severe forms of G6PD deficiency may present impaired NADPH oxidase activity and become susceptible to recurrent infections. This fact, highlights the importance to characterize the immunopathologic mechanisms underlying the susceptibility to infections in patients with G6PD deficiency. Here we report the first two cases of G6PD deficiency with Bacille Calmette-Guérin (BCG) adverse effect, besides jaundice, hemolytic anemia and recurrent infections caused by Staphylococcus aureus. The qualitative G6PD screening was performed and followed by oxidative burst analysis using flow cytometry. Genetic and in silico analyses were carried out by Sanger sequencing and mutation pathogenicity predicted using bioinformatics tools, respectively. Activated neutrophils and monocytes from patients displayed impaired oxidative burst. The genetic analysis revealed the novel missense mutation c.1157T>A/p.L386Q in G6PD. In addition, in silico analysis indicated that this mutation is pathogenic, thereby hampering the oxidative burst of neutrophils and monocytes from patients. Our data expand the clinical and genetic spectrum of G6PD deficiency, and suggest that impaired oxidative burst in this severe primary immune deficiency is an underlying immunopathologic mechanism that predisposes to mycobacterial infections.

Molecular detection and antimicrobial resistance profile of zoonotic Salmonella enteritidis isolated from broiler chickens in Kohat, Pakistan

Background Salmonella enteritidis infection is a frequently encountered zoonotic problem, occurring with concerning regularity in recent years on a worldwide basis. The study that we undertook for the first time detected S. enteritidis and associated antimicrobial resistance pattern in broiler chickens. Methods A total of 150 different poultry samples were first enriched and grown on selective media, and then processed for molecular detection of S. enteritidis by amplification of the spvb gene. Results The overall detection rate of S. enteritidis was 23.3% (n = 35), while an increased detection rate of S. enteritidis was found in the chicken breast tissue (n = 9; 30%). When antibiogram was tested for S. enteritidis against common antibiotics, increased resistance to ampicillin (n = 29; 82.2%), tetracycline (n = 28; 80%), augmentin (n = 27; 77.14%), and chloramphenicol (n = 19; 54.2%) was observed. Multidrug resistance was reported in 54.8% (n = 19) of the S. enteritidis isolates, while 20% (n = 07) of isolates were extensively drug resistant. Conclusion The present study for the first time reports S. enteritidis on the basis of spvb gene detection. The increased drug resistance in S. enteritidis is an emerging problem that could negatively impact efforts to prevent and treat broiler‐transmitted S. enteritidis.

Beta-lactamase-producing Pseudomonas aeruginosa: Phenotypic characteristics and molecular identification of virulence genes

Background Pseudomonas aeruginosa causes common infections in immunocompromised and cystic fibrosis patients. However, drug resistance capability and release of virulence factors play a key role in bacterial pathogenicity. Methods Beta‐lactamase‐producing clinical isolates of P. aeruginosa were screened for biofilm formation and pigment production. Subsequently, all the isolates were subjected to the detection of six virulence genes (OprI, OprL, LasB, PlcH, ExoS, and ToxA). Results Among beta‐lactamase‐producing isolates (n = 54), about 85.18% (n = 46) were biofilm producers. Pigment production was observed in 92.59% (n = 50) isolates. Clinical samples were subsequently screened for detection of virulence factors. Among them, 40.74% (n = 22) isolates were found to be OprI positive, while 29.62% (n = 16) were OprL producers. In the case of LasB and PlcH, 24% (n = 13) and 18.5% (n = 10) isolates produced these virulence genes, respectively. Among the isolates, 37.03% (n = 20) and 33.33% (n = 18) expressed virulence factors ExoS and ToxA, respectively. Furthermore, 42.59% (n = 23) isolates coproduced more than one type of virulence factors. Conclusion In the current study, pigment display, biofilm formation, and virulence genes were detected in P. aeruginosa clinical isolates. Such factors could be crucial in the development of drug resistance.

A novel mutation in the HPGD gene causing primary hypertrophic osteoarthropathy with digital clubbing in a Pakistani family

Primary hypertrophic osteoarthropathy (PHO) is a congenital multisystemic entity characterized by three major clinical symptoms: pachydermia, periostosis, and digital clubbing. Recently it has been reported that pathogenic mutations in two genes are known to be associated with PHO: HPGD and SLCO2A1. In the present study, a five‐generation consanguineous Pakistani family harboring primary hypertrophic osteoarthropathy in autosomal‐recessive pattern was ascertained. Whole genome single nucleotide polymorphisms (SNPs) genotyping and sequence analysis revealed a novel homozygous missense mutation (c.577T˃C) of the human HPGD gene in all affected members of the family. The study presented here demonstrate the first case of primary hypertrophic osteoarthropathy reported in Pashtun population.

Molecular identification of TEM-116 beta-lactamase gene in isolates of pathogenic Pseudomonas aeruginosa : A first report from Pakistan

Purpose: Purpose: To determine TEM-116 beta-lactamase gene prevalence in drug-resistant Pseudomonas aeruginosa isolates from Pakistan. Methods: Sequence analysis of TEM beta-lactamase isolates and their antibiotic susceptibility patterns were carried out. Quantitative bacteriostatic concentrations for commonly used antibiotics were measured against TEM-116 beta-lactamase isolates. Results: Among the 102 isolates of P. aeruginosa , 23 (22.5 %) were TEM beta-lactamase producers. Sequence analysis of TEM gene from selected isolates showed homology with TEM-116. Two mutations at positions 84 (p.Val84Ile) and 184 (p.Ala184Val) were documented. The TEM-116 isolates exhibited 100 % resistance to sulphamethoxazole/trimethoprim, amoxycillin/clavulanic acid and doxycycline, but showed sensitivity to levofloxacin, norfloxacin and amikacin. One TEM-116 P. aeruginosa (PA11) isolate was resistant to all available antibiotics. Conclusion: These results reveal increased antibiotic resistance in the TEM-116 P. aeruginosa isolates studied, a phenomenon which will be helpful in understanding the molecular mechanisms of antibiotic resistance in P. aeruginosa . Keywords: P. aeruginosa , Clinical isolates, Sequencing, TEM-116, Antibiotic susceptibility