Multifaceted Impacts of Plant-Beneficial Pseudomonas spp. in Managing Various Plant Diseases and Crop Yield Improvement

The modern agricultural system has issues with the reduction of agricultural productivity due to a wide range of abiotic and biotic stresses. It is also expected that in the future the entire world population may rapidly increase and will surely demand more food. Farmers now utilize a massive quantity of synthetic fertilizers and pesticides for disease management and to increase food production. These synthetic fertilizers badly affect the environment, the texture of the soil, plant productivity, and human health. However, agricultural safety and sustainability depend on an ecofriendly and inexpensive biological application. In contrast to synthetic fertilizers, soil inoculation with plant-growth-promoting rhizobacteria (PGPR) is one of the excellent alternative options. In this regard, we focused on the best PGPR genera, Pseudomonas, which exists in the rhizosphere as well as inside the plant's body and plays a role in sustainable agriculture. Many Pseudomonas spp. control plant pathogens and play an effective role in disease management through direct and indirect mechanisms. Pseudomonas spp. fix the amount of atmospheric nitrogen, solubilize phosphorus and potassium, and also produce phytohormones, lytic enzymes, volatile organic compounds, antibiotics, and secondary metabolites during stress conditions. These compounds stimulate plant growth by inducing systemic resistance and by inhibiting the growth of pathogens. Furthermore, pseudomonads also protect plants during different stress conditions like heavy metal pollution, osmosis, temperature, oxidative stress, etc. Now, several Pseudomonas-based commercial biological control products have been promoted and marketed, but there are a few limitations that hinder the development of this technology for extensive usage in agricultural systems. The variability among the members of Pseudomonas spp. draws attention to the huge research interest in this genus. There is a need to explore the potential of native Pseudomonas spp. as biocontrol agents and to use them in biopesticide development to support sustainable agriculture.

Culturally adapted psychosocial interventions (CaPSI) for early psychosis in a low-resource setting: study protocol for a large multi-center RCT

BACKGROUND

Psychosis treatment guidelines recommend cognitive behaviour therapy (CBT) and family intervention (FI), for all patients with first episode psychosis (FEP), though guidance borrows heavily from literature in adults from high income countries. To our knowledge, there are few randomized controlled trials (RCTs) examining the comparative effect of these commonly endorsed psychosocial interventions in individuals with early psychosis from high-income countries and no such trials from low and middle-income countries (LMICs). The present study aims to confirm the clinical-efficacy and cost-effectiveness of delivering culturally adapted CBT (CaCBT) and culturally adapted FI (CulFI) to individuals with FEP in Pakistan.

METHOD

A multi-centre, three-arm RCT of CaCBT, CulFI, and treatment as usual (TAU) for individuals with FEP (n = 390), recruited from major centres across Pakistan. Reducing overall symptoms of FEP will be the primary outcome. Additional aims will include improving patient and carer outcomes and estimating the economic impact of delivering culturally appropriate psychosocial interventions in low-resource settings. This trial will assess the clinical-efficacy and cost-effectiveness of CaCBT and CulFI compared with TAU in improving patient (positive and negative symptoms of psychosis, general psychopathology, depressive symptoms, quality of life, cognition, general functioning, and insight) and carer related outcomes (carer experience, wellbeing, illness attitudes and symptoms of depression and anxiety).

CONCLUSIONS

A successful trial may inform the rapid scale up of these interventions not only in Pakistan but other low-resource settings, to improve clinical outcomes, social and occupational functioning, and quality of life in South Asian and other minority groups with FEP.

TRIAL REGISTRATION

NCT05814913.

Redescription and resurrection of the status of Joyeuxiella gervaisi () (Eucestoda, Dipylidiidae)

A study of the parasite fauna of feral cats in Dubai revealed the presence of two Joyeuxiella species, J. pasqualei (Diamare, 1893) and J. fuhrmanni (Baer, 1924). While the wide distribution of J. pasqualei includes countries of the Middle East, Africa, Asia and Europe, J. fuhrmanni was previously reported from felid hosts from southern Africa and has not been found in other cat parasite surveys in the Middle East, except from Dubai. The availability of historical references, however, raised doubts about the correctness of the allocation of the small Joyeuxiella sp. from Dubai cats to J. fuhrmanni and for this reason, a reexamination of stored material in the parasite collection of the Central Veterinary Research Laboratory in Dubai was carried out. A total of 40 specimens of the small Joyeuxiella sp. with a strobila length between 30 and 60 mm and consisting of 52 to 85 segments obtained from domestic cats and formerly allocated to J. fuhrmanni were studied. In complete specimens, 10 - 13 rows of rostellar hooks were counted. Mature segments were wider than long, round testes were concentrated posterior to coiled vasa deferentia and did not reach the anterior rim of the proglottids. Narrow cirri reached up to 520 μm in length. Gravid segments were longer than wide and egg capsules were restricted to the space between longitudinal excretory vessels. The examination revealed that the morphology of these cestodes matched the main characteristics of J. fuhrmanni. However, the little known cestode, J. gervaisi (Setti, 1895), that had been described from Genetta abyssinica imported from Eritrea 29 years earlier and was declared a species inquirenda met the same main morphological criteria. In this paper, the status of J. gervaisi as a valid species was resurrected and J. fuhrmanni was declared a junior synonym.

Evaluation of potential ecological risk assessment of toxic metal (lead) in contaminated meadows in the vicinity of suburban city: soil vs forages vs livestock

Heavy metal toxicity is becoming an increasing concern for environmental, human and animal health. The current research analyzed the lead (Pb) contamination in the food chain under three different irrigation sources (ground, canal, and wastewater). Soil, plant and animal samples were collected from the Jhang district of Pakistan and processed with an atomic absorption spectrophotometer. Lead concentration varied in the samples as: 5.22-10.73 mg/kg in soil, 2.46-10.34 mg/kg in forages and 0.736-2.45 mg/kg in animal samples. The observed lead concentration in forage and animal blood samples was higher than the standard limits. The pollution load index (0.640-1.32) in soil showed that lead contamination mainly took place at the wastewater irrigating sites. Bio-concentration factor values (0.313-1.15) were lower than one in all samples except Zea mays, showing that lead metal was actively taken up by Zea mays tissues from the soil. Enrichment factor values ranged from 0.849-3.12, showing a moderate level of lead enrichment. Daily intake and health risk index varied between 0.004-0.020 mg/kg/day and 0.906-4.99, respectively. All the samples showed maximum lead concentration at the wastewater irrigating site compared to the ground or canal water application sites. These results recommended that consistent application of wastewater for forage irrigation must be avoided to prevent health hazards associated with lead in the animal and human food chain. Government must implement adequate strategies to protect the animal and human health from the harms of toxic heavy metals.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Silencing of the phosphofructokinase gene impairs glycolysis and causes abnormal locomotion in the subterranean termite Reticulitermes chinensis Snyder

Phosphofructokinase (PFK) is a rate-limiting enzyme in glycolysis, but its linkage with locomotion in termites is not well understood, despite the demonstrated involvement of this gene in the locomotion of different animals. Here, we investigated the effect of the pfk gene on locomotion in the subterranean termite Reticulitermes chinensis Snyder through RNA interference and the use of an Ethovision XT tracking system. The knockdown of pfk resulted in significantly decreased expression of the pfk gene in different castes of termites. The pfk-silenced workers displayed higher levels of glucose but lower levels of nicotinamide adenine dinucleotide (NADH) and adenosine triphosphate (ATP) production and decreased activity of the PFK enzyme. Furthermore, abnormal locomotion (decreased distance travelled, velocity and acceleration but increased turn angle, angular velocity and meander) was observed in different castes of pfk-silenced termites. We found caste-specific locomotion among workers, soldiers and dealates. Additionally, soldiers and dealates showed higher velocity in the inner zone than in the wall zone, which is considered an effective behaviour to avoid predation. These findings reveal the close linkage between the pfk gene and locomotion in termites, which helps us to better understand the regulatory mechanism and caste specificity of social behaviours in social insects.

Feasibility study of culturally adapted cognitive behaviour therapy for psychosis in Pakistan

Background

It is becoming well established that CBT is both effective and cost efficient in the treatment of positive and negative symptoms of schizophrenia. However, there is a need to adapt CBT to the cultural, linguistic, and socioeconomic context of diverse cultural groups. We aimed to establish the feasibility of culturally adaptive cognitive behavior therapy for treatment of psychosis in a low-income country.

Methods

This is a rater-blind, randomized, controlled trial of the use of CBT in patients with psychosis from a low-income country. Patients with a DSM-IV diagnosis of schizophreniform disorder were assessed using Positive and Negative Syndrome Scale for Schizophrenia (PANSS), PSYRATS (Psychotic Symptom Rating Scales), and the Insight Scale. Participants were randomized into the intervention group (n = 18) and TAU group (n = 18). The intervention group received 12 weekly sessions of culturally adapted CBT for psychosis (CaCBTp).

Results

There were no significant differences between the two groups at baseline. At three months follow-up, there was a statistically significant improvement in the CaCBTp group on PANSS general Psychopathology subscale, PANSS overall score and Insight scale, as compared to the TAU group. The CaCBTp group had lower scores on PANSS positive, PANSS negative sub-scales, and the two subscales of Psychotic Symptom Rating Scale, but differences were not statistically significant.

Conclusion

Culturally adapted CBT added to pharmacological treatment as usual was acceptable to patients and was helpful in reduction of severity of psychotic symptoms. Adjunctive culturally adapted CBT should be further investigated in this population.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Cognitive function in early psychosis patients from a low-income country

Background

Cognitive impairments are well established findings in schizophrenia and are associated with significant impairment of social functioning. Episodic memory, working memory and executive function test scores are typically 1 standard deviation below healthy controls. There are reports suggesting the presence of neurocognitive deficits prior to illness onset, opening the possibility of using cognitive profiles as disease markers. Interest in exploring cognitive functioning in early stages schizophrenia has continued to grow, as earlier treatments could possibly lead to improved outcomes.

Methods

This is a cross-sectional assessment of cognitive profiles in patients with early psychosis. A total of 51 patients suffering from psychosis in the age group of 18–65 years were recruited and matched with 51 healthy controls. A wide range of neurocognitive domains were assessed using standardised neuropsychological tests.

Results

There was evidence of statistically significant impairments in cognitive functioning across a broad range of cognitive domains in early-psychosis patients, as compared to healthy controls. More pronounced deficits were seen in executive function tests.

Conclusions

To our knowledge, this is the first study to report cognitive deficits across a range of domains in patients with first episode psychosis from a low-income country. This study found deficits across multiple domains, including language, memory, attention, executive function, and visuospatial function in patients with early psychosis. Evidence of neuropsychological deficits in the early course of the disease may highlight crucial therapeutic windows for both pharmacological treatments and cognitive rehabilitation. This may improve functional outcomes in this patient group in the longer term.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Effects of bioreactor hydrodynamics on the physiology of Streptomyces

Streptomyces are filamentous bacteria which are widely used industrially for the production of therapeutic biomolecules, especially antibiotics. Bioreactor operating conditions may impact the physiological response of Streptomyces especially agitation and aeration as they influence hydromechanical stress, oxygen and nutrient transfer. The understanding of the coupling between physiological response and bioreactor hydrodynamics lies on a simultaneous description of the flow and transfers encountered by the bacteria and of the microbial response in terms of growth, consumption, morphology, production or intracellular signals. This article reviews the experimental and numerical works dedicated to the study of the coupling between bioreactor hydrodynamics and antibiotics producing Streptomyces. In a first part, the description of hydrodynamics used in these works is presented and then the main relations used. In a second part, the assumptions made in these works are discussed and put into emphasize. Lastly, the various Streptomyces physiological responses observed are detailed and compared.

Oxygen supply controls the onset of pristinamycins production by Streptomyces pristinaespiralis in shaking flasks

Antibiotics are secondary metabolites, generally produced during stationary phase of growth under different nutritional and hydrodynamic stresses. However, the exact mechanisms of the induction of antibiotics production are still not clearly established. In a previous study, the induction of pristinamycins production by Streptomyces pristinaespiralis as well as product concentrations were correlated with power dissipation per unit of volume (P/V) in shaking flasks. In this study, detailed kinetics of growth, substrate consumption, oxygen transfer rate and pristinamycins production under varying P/V conditions have been obtained and analyzed. Our results showed that higher P/V resulted in a higher concentration of biomass and promoted an earlier nutrient limitation and ultimately an earlier induction of pristinamycins production. The maximal specific growth rate, specific oxygen consumption rate and specific consumption rate of glutamate increased with P/V while influence was less marked with specific consumption rate of glucose, arginine, ammonium ions and phosphate. When oxygen uptake rate (OUR) was limited by free-surface oxygen transfer, pristinamycins production was not detected despite the occurrence of nitrogen and/or phosphate sources limitation. The threshold value for OUR observed was around 25 mmol L(-1) h(-1). This suggested that a limitation in nitrogen and/or phosphate alone was not sufficient to induce pristinamycins production by S. pristinaespiralis pr11. To induce this production, the oxygen transfer had to be non-limiting.

Role of Bi-pap in acute respiratory failure due to acute exacerbation of COPD

OBJECTIVE

To assess the efficacy of Bi-level Positive Airway Pressure (Bi-pap), administered by nasal mask in patients with acute respiratory failure due to acute exacerbation of COPD.

DESIGN

Prospective non-randomized study in a hospital setting.

METHODS

Eighteen patients were recruited from those admitted in the Chest Unit of Jinnah Postgraduate Medical Centre, Karachi with acute exacerbation of COPD. Along with conventional treatment, Bi-pap was administered by a nasal mask. Arterial blood gas analysis, respiratory and heart rate and subjective sensation of dyspnoea, before and during Bi-pap application were monitored.

RESULTS

The respiratory rate decreased from 33.2 +/- 5.3/min to 22.0 +/- 3.5 (P < 0.001), heart rate also decreased from 113.2 +/- 7.6/min to 90.2 +/- 11.9 (P < 0.001). A rise in pH was observed from 7.2 +/- 0.09 to 7.4 +/- 0.06 (P > 0.41 n.s.), PaCO2 decreased from 76.5 +/- 15.5 to 51.3 +/- 10.5 (P < 0.001). PaO2 also increased from 52.1 +/- 14.3 to 62.9 +/- 11.5 (P < 0.01). The mean hospital stay was shorter i.e., 10.6 +/- 5.6 days and the hospital mortality rate 11.1%. Bi-pap administered by nasal mask was generally well tolerated with few minor complications.

CONCLUSION

Bi-pap is particularly useful in patients presenting with acute respiratory failure due to acute exacerbation of COPD particularly in our setting where invasive ventilation is not easily available.