Impact of problematic mobile phone use among nursing students in India: Exploring associations with depression, insomnia, self-esteem and satisfaction with life

AIM

This research aimed to determine the impact of problematic mobile phone use on negative mental health outcomes among nursing students in India, highlighting the necessity for targeted interventions and support mechanisms to enhance the overall well-being and adaptability of future healthcare professionals.

METHODS

A cross-sectional survey was conducted in three randomly selected nursing colleges in South India, employing validated and standardized tools such as the Mobile Phone Problematic Use Scale, Patient Health Questionnaire, Insomnia Severity Index Scale, Satisfaction with Life Scale and Rosenberg Self-Esteem Scale.

RESULTS

The study included 402 nursing students with an average age of 20.47 years, revealing a 39% prevalence of severe problematic mobile phone usage. Positive correlations were observed between mobile phone problematic use and age, depression and insomnia. Additionally, strong negative correlations were found between satisfaction with life and self-esteem. Depression and satisfaction with life served as chain mediators in the impact of self-esteem on problematic mobile phone use, and both self-esteem and satisfaction with life negatively predicted problematic mobile phone use.

CONCLUSION

The study highlights a prevalent issue of problematic mobile phone use among nursing students, indicating a pressing need for timely intervention, as it correlates with depression, sleep insomnia, low self-esteem and life dissatisfaction.

Nurses' Knowledge and Subjective Strain in Delirium Care: Impact of a Web-based Instructional Module on Nurses Competence

Background

Delirium, a prevalent condition among elderly individuals admitted to hospitals, particularly in intensive care settings, necessitates specialized medical intervention. The present study assessed the proficiency of nurses in the management of delirium and their subjective experience of stress while providing care for patients with delirium in emergency rooms and critical care units.

Materials and methods

The study adopted a quantitative descriptive approach, utilizing standardized self-reporting measures that assessed the nurses' expertise and perceived burden of care. A cohort of 86 nurses from a tertiary care hospital in North India participated in the study. Additionally, the impact of the web-based instructional module in enhancing the nurses' knowledge in delirium management was assessed by one group pretest-posttest quasi-experimental study.

Findings

The research revealed that nurses exhibited significant deficiencies in their knowledge, particularly in relation to the symptoms and causes of delirium. The most significant source of subjective stress was attributed to hyperactive delirium-associated behaviors, characterized by uncooperative and aggressive conduct. The utilization of the web-based instructional program significantly enhanced the comprehension of nurses about the management of delirium.

Conclusion

This study revealed a significant knowledge gap among nurses in delirium management and emphasizes the considerable subjective stress, particularly in dealing with hyperactive delirium-associated behaviors. The positive impact of the web-based instructional program underscores its potential as a valuable tool for enhancing nurses' knowledge and addressing these challenges in healthcare settings.

How to cite this article

Jose S, Cyriac MC, Dhandapani M. Nurses' Knowledge and Subjective Strain in Delirium Care: Impact of a Web-based Instructional Module on Nurses Competence. Indian J Crit Care Med 2024;28(2):111-119.

Olfactomedin-4 + neutrophils exacerbate intestinal epithelial damage and worsen host survival after Clostridioides difficile infection

Neutrophils are key first responders to Clostridioides difficile infection (CDI). Excessive tissue and blood neutrophils are associated with worse histopathology and adverse outcomes, however their functional role during CDI remains poorly defined. Utilizing intestinal epithelial cell (IEC)-neutrophil co-cultures and a pre-clinical animal model of CDI, we show that neutrophils exacerbate C. difficile -induced IEC injury. We utilized cutting-edge single-cell transcriptomics to illuminate neutrophil subtypes and biological pathways that could exacerbate CDI-associated IEC damage. As such, we have established the first transcriptomics atlas of bone marrow (BM), blood, and colonic neutrophils after CDI. We found that CDI altered the developmental trajectory of BM and blood neutrophils towards populations that exhibit gene signatures associated with pro-inflammatory responses and neutrophil-mediated tissue damage. Similarly, the transcriptomic signature of colonic neutrophils was consistent with hyper-inflammatory and highly differentiated cells that had amplified expression of cytokine-mediated signaling and degranulation priming genes. One of the top 10 variable features in colonic neutrophils was the gene for neutrophil glycoprotein, Olfactomedin 4 (OLFM4). CDI enhanced OLFM4 mRNA and protein expression in neutrophils, and OLFM4 + cells aggregated to areas of severe IEC damage. Compared to uninfected controls, both humans and mice with CDI had higher concentrations of circulating OLFM4; and in mice, OLFM4 deficiency resulted in faster recovery and better survival after infection. Collectively, these studies provide novel insights into neutrophil-mediated pathology after CDI and highlight the pathogenic role of OLFM4 + neutrophils in regulating CDI-induced IEC damage.

One Sentence Summary

Utilizing single-cell transcriptomics, IEC-epithelial co-cultures, and pre-clinical models of CDI, we have identified a subset of neutrophils that are marked by OLFM4 expression as pathogenic determinants of IEC barrier damage after CDI.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

Mental Health Outcomes of Perceived Stress, Anxiety, Fear and Insomnia, and the Resilience among Frontline Nurses Caring for Critical COVID-19 Patients in Intensive Care Units

Background

The coronavirus disease-2019 (COVID-19) pandemic has led to a significant disruption in healthcare delivery and poses a unique long-term stressor among frontline nurses. Hence, the investigators planned to explore the adverse mental health outcomes and the resilience of frontline nurses caring for COVID-19 patients admitted in intensive care units (ICUs).

Materials and methods

A cross-sectional online survey using Google form consisted of questionnaires on perceived stress scale (PSS-10), generalized anxiety disorder scale (GAD-7), Fear Scale for Healthcare Professionals regarding the COVID-19 pandemic, insomnia severity index, and the Connor-Davidson Resilience Scale-10 (CD-RISC) were administered among the nurses working in COVID ICUs of a tertiary care center in North India.

Results

A considerable number of subjects in the study reported symptoms of distress (68.5%), anxiety (54.7%), fear (44%), and insomnia (31%). Resilience among the frontline nurses demonstrated a moderate to a high level with a mean percentage score of 77.5 (31.23 ± 4.68). A negative correlation was found between resilience and adverse mental outcomes; hence, resilience is a reliable tool to mitigate the adverse psychological consequences of the COVID-19 pandemic.

Conclusion

Emphasizing the well-being of the nurses caring for critical COVID-19 patients during the pandemic is necessary to enable them to provide high-quality nursing care.

How to cite this article

Jose S, Cyriac MC, Dhandapani M, Mehra A, Sharma N. Mental Health Outcomes of Perceived Stress, Anxiety, Fear and Insomnia, and the Resilience among Frontline Nurses Caring for Critical COVID-19 Patients in Intensive Care Units. Indian J Crit Care Med 2022;26(2):174–178.

Health Problems and Skin Damages Caused by Personal Protective Equipment: Experience of Frontline Nurses Caring for Critical COVID-19 Patients in Intensive Care Units

BACKGROUND

In the event of coronavirus disease-2019 (COVID-19) spread worldwide, frontline healthcare workers play a key role in the containment of this devastating pandemic, and to prevent the cross-transmission and gain confidence in battle with the pandemic, they are wearing personal protective equipment (PPE).

AIM AND OBJECTIVE

To explore the adverse health problems and skin reactions caused by the use of PPEs among the frontline nurses in the ICUs of COVID hospital.

MATERIALS AND METHODS

A cross-sectional study was conducted using an online-based questionnaire assessing the physical problems, and adverse skin reactions of PPEs were sent among the 150 frontline nurses in ICUs of COVID hospital. The collected data were analyzed using descriptive statistics.

RESULTS

We got 137 valid responses from frontline nurses, and the most common adverse health effects expressed by them were headache (73.4%), extreme sweating (59.6%), and difficulty in breathing (36.7%); 91.7% complained about the fogging of the goggle. Majority of frontline nurses expressed nasal bridge scarring (76.64%) and indentation and pain on the back of the ears (66.42%) as the adverse skin reactions after wearing N95 masks. The common skin problems identified due to double gloving of latex gloves were excessive skin soakage with sweat (70.07%) and skin chapping (19%). The protective clothing caused minimal adverse reactions, and excessive sweating (71.53%) was the most reported.

CONCLUSION

The healthcare workers wearing PPE for a prolonged period show significant adverse effects, so appropriate strategies should be taken to prevent the adverse effects by designing effective PPEs and education of preventive measures among healthcare workers.

HOW TO CITE THIS ARTICLE

Jose S, Cyriac MC, Dhandapani M. Health Problems and Skin Damages Caused by Personal Protective Equipment: Experience of Frontline Nurses Caring for Critical COVID-19 Patients in Intensive Care Units. Health Problems and Skin Damages Caused by Personal Protective Equipment: Experience of Frontline Nurses Caring for Critical COVID-19 Patients in Intensive Care Units. Indian J Crit Care Med 2021;25(2):134-139.

Burnout and Resilience among Frontline Nurses during COVID-19 Pandemic: A Cross-sectional Study in the Emergency Department of a Tertiary Care Center, North India

BACKGROUND

The COVID-19 pandemic had a massive impact on healthcare systems, increasing the risks of psychological distress in health professionals. Burnout is a prolonged response to chronic emotional and interpersonal stressors on the job and is defined by the three dimensions of emotional exhaustion, cynicism, and personal inefficacy.

METHODOLOGY

A cross-sectional descriptive design was used to assess the burnout and resilience among frontline nurses in the emergency department of a tertiary care center in North India during COVID-19 pandemic. The sample consisted of 120 frontline nurses working in the emergency department, selected by a simple random sampling method. Data were collected using the Maslach burnout inventory-general survey and the Connor-Davidson Resilience Scale.

RESULTS

The nurses in the emergency during pandemic experienced a moderate-to-severe level of burnout in emotional exhaustion (29.13 ± 10.30) and depersonalization (12.90 ± 4.67) but mild-to-moderate level of burnout in reduced personal accomplishment (37.68 ± 5.17) and showed a moderate to a high level of resilience (77.77 ± 12.41). The two metrics of burnout viz., emotional exhaustion and personal inefficacy had a significantly negative correlation with resilience among the frontline nurses in the emergency (r = 0.25, p < 0.05 and r = 0.31, p < 0.01, respectively). A significant negative correlation has been identified between burnout and resilience that informs the role of resilience in alleviating burnout during this pandemic.

CONCLUSION

Effective interventions for improving resilience are needed to relieve nurses' burnout and workplace stressors. Also, the administration should ensure a healthy workplace and adopt a positive attitude and harmonious relationship with the frontline workers in the mitigation of the pandemic.

HOW TO CITE THIS ARTICLE

Jose S, Dhandapani M, Cyriac MC. Burnout and Resilience among Frontline Nurses during COVID-19 Pandemic: A Cross-sectional Study in the Emergency Department of a Tertiary Care Center, North India. Indian J Crit Care Med 2020;24(11):1081-1088.

Prevalence and Correlates of Depressive Symptoms among Medical Students: a Cross-sectional Single-centre Study

BACKGROUND

Depressive symptoms are common among medical students. The aim of the present study was to determine the prevalence and risk factors of depressive symptoms among medical students in Sultan Qaboos University in Oman.

METHOD

A cross-sectional study was conducted among a random sample selected from 1041 medical students at Sultan Qaboos University, Oman. The Patient Health Questionnaire-9 (PHQ-9) was used to screen for depressive symptoms. A logistic regression model was used to determine risk factors for depressive symptoms.

RESULTS

Of 197 medical students selected, 189 (61 men and 128 women) responded. The PHQ-9 results showed that the prevalence of depressive symptoms was 41.3%. In multivariate analysis, female students were more likely than male students to develop depression (adjusted odds ratio = 2.866, p = 0.004). Medical students with a family history of depression were more likely to develop depression than those without a family history of depression (adjusted odds ratio = 4.150, p = 0.014).

CONCLUSIONS

Depressive symptoms are common among medical students in Sultan Qaboos University. Risk factors for depressive symptoms are female sex and family history of depression.

Perioperative Management of Sickle Cell Disease in Paediatric Cardiac Surgery

In sickle cell disease, cardiopulmonary bypass may induce red cell sickling. Partial exchange transfusion reduces the circulating haemoglobin S level. We report the management of a child with sickle cell disease who required surgical closure of a ventricular septal defect. Preoperative exchange transfusion of 50% of the total blood volume was performed with fresh packed red cells over three days. Further exchange transfusion was performed as cardiopulmonary bypass commenced. The haemoglobin S level was reduced from 76% to 37%. The blood removed from the patient during the exchanges was processed allowing storage and re-infusion of the patient's plasma and platelets. Combined preoperative and intraoperative exchange transfusions, instead of a single stage 50% volume exchange, was effective and potentially avoids larger haemodynamic effects. Cardiopulmonary bypass was conducted at normothermia and cold cardioplegia was avoided (fibrillatory arrest was used during the surgical repair).

The use of funnel plots with regression as a tool to visually compare HIV treatment outcomes between centres adjusting for patient characteristics and size: a UK Collaborative HIV Cohort study

Objectives

A measure used for assessing the effectiveness of HIV care and comparing clinical centres is the proportion of people starting antiretroviral therapy (ART) with viral suppression (VS) after 1 year. We propose a method that adjusts for patients’ demographic characteristics, and visually compares this measure between different sites accounting for centre size.

Methods

We analysed viral load measurements for UK Collaborative HIV Cohort (UK CHIC) patients starting ART between 2006 and 2013. We used logistic regression to estimate the proportion with VS after 1 year of ART adjusted for patient mix (in terms of age and a combined gender/ethnicity/acquisition mode variable) and calendar year. We compared outcomes between centres using funnel plots which account for centre size.

Results

The overall proportion of the cohort with VS 1 year after starting ART was 90% and increased from 83% to 93% between 2006 and 2013. VS was lower in younger individuals. White men who have sex with men (MSM) had the highest (94%), and black African (81%) and white (82%) heterosexual women the lowest proportions achieving VS. Comparing the unadjusted funnel plot with the adjusted, there were movements of some centres from outside to inside the 95% contour limits, which was largely explained by the patient mix of these centres.

Conclusions

VS 1 year after ART start was associated with demographic characteristics and centre size; therefore, to compare the performances of centres, adjustment for these factors is required. Adjusted funnel plot is an effective tool which accounts for both the demographic characteristics and the centre size. Social factors, rather than treatment decisions within the control of the centres, may drive differences in outcomes.

A tale of two countries: all-cause mortality among people living with HIV and receiving combination antiretroviral therapy in the UK and Canada

Objectives

We sought to compare all‐cause mortality of people living with HIV and accessing care in Canada and the UK.

Methods

Individuals from the Canadian Observational Cohort (CANOC) collaboration and UK Collaborative HIV Cohort (UK CHIC) study who were aged ≥ 18 years, had initiated antiretroviral therapy (ART) for the first time between 2000 and 2012 and who had acquired HIV through sexual transmission were included in the analysis. Cox regression was used to investigate the difference in mortality risk between the two cohort collaborations, accounting for loss to follow‐up as a competing risk.

Results

A total of 19 960 participants were included in the analysis (CANOC, 4137; UK CHIC, 15 823). CANOC participants were more likely to be older [median age 39 years (interquartile range (IQR): 33, 46 years) vs. 36 years (IQR: 31, 43 years) for UK CHIC participants], to be male (86 vs. 73%, respectively), and to report men who have sex with men (MSM) sexual transmission risk (72 vs. 56%, respectively) (all P < 0.001). Overall, 762 deaths occurred during 98 798 person‐years (PY) of follow‐up, giving a crude mortality rate of 7.7 per 1000 PY [95% confidence interval (CI): 7.1, 8.3 per 1000 PY]. The crude mortality rates were 8.6 (95% CI: 7.4, 10.0) and 7.5 (95% CI: 6.9, 8.1) per 1000 PY among CANOC and UK CHIC study participants, respectively. No statistically significant difference in mortality risk was observed between the cohort collaborations in Cox regression accounting for loss to follow‐up as a competing risk (adjusted hazard ratio 0.86; 95% CI: 0.72–1.03).

Conclusions

Despite differences in national HIV care provision and treatment guidelines, mortality risk did not differ between CANOC and UK CHIC study participants who acquired HIV through sexual transmission.

Development and application of a new measure of engagement in out-patient HIV care

OBJECTIVES

Commonly used measures of engagement in HIV care do not take into account that the frequency of attendance is related to changes in treatment and health status. This study developed a new measure of engagement in care (EIC) incorporating clinical factors.

METHODS

We conducted semi-structured interviews with eight HIV physicians to identify factors associated with the timing of patients' next scheduled appointments. These factors informed the development of an algorithm to classify each month of follow-up as "in care" (on or before the time of the next expected attendance) or "out of care" (after the time of the next expected attendance). The EIC algorithm was applied to data from the UK Collaborative HIV Cohort (UK CHIC) study, a large clinical cohort study.

RESULTS

The interviews indicated that time to next appointment varied depending on psychosocial and physical comorbidities, and clinical factors (time since diagnosis, AIDS diagnosis, treatment status, CD4 count and viral load). The resulting EIC algorithm was applied to 44 432 patients; 83.9% of the 3 021 224 person-months were "in care". Greater EIC was independently associated with older age, white ethnicity, HIV acquisition through sex between men, current use of antiretroviral therapy (ART), a higher nadir CD4 count, later calendar year and being seen at the clinic for the first time within the last year.

CONCLUSIONS

This algorithm describing engagement in HIV care incorporates a time-updated measure of patients' treatment and health status. It adds to the options available for measuring this key performance indicator.

Treatment-limiting renal tubulopathy in patients treated with tenofovir disoproxil fumarate

OBJECTIVES

Tenofovir disoproxil fumarate (TDF) is widely used in the treatment or prevention of HIV and hepatitis B infection. TDF may cause renal tubulopathy in a small proportion of recipients. We aimed to study the risk factors for developing severe renal tubulopathy.

METHODS

We conducted an observational cohort study with retrospective identification of cases of treatment-limiting tubulopathy during TDF exposure. We used multivariate Poisson regression analysis to identify risk factors for tubulopathy, and mixed effects models to analyse adjusted estimated glomerular filtration rate (eGFR) slopes.

RESULTS

Between October 2002 and June 2013, 60 (0.4%) of 15,983 patients who had received TDF developed tubulopathy after a median exposure of 44.1 (IQR 20.4, 64.4) months. Tubulopathy cases were predominantly male (92%), of white ethnicity (93%), and exposed to antiretroviral regimens that contained boosted protease inhibitors (PI, 90%). In multivariate analysis, age, ethnicity, CD4 cell count and use of didanosine or PI were significantly associated with tubulopathy. Tubulopathy cases experienced significantly greater eGFR decline while receiving TDF than the comparator group (-6.60 [-7.70, -5.50] vs. -0.34 [-0.43, -0.26] mL/min/1.73 m²/year, p < 0.0001).

CONCLUSIONS

Older age, white ethnicity, immunodeficiency and co-administration of ddI and PI were risk factors for tubulopathy in patients who received TDF-containing antiretroviral therapy. The presence of rapid eGFR decline identified TDF recipients at increased risk of tubulopathy.

Virological failure and development of new resistance mutations according to CD4 count at combination antiretroviral therapy initiation

Objectives

No randomized controlled trials have yet reported an individual patient benefit of initiating combination antiretroviral therapy (cART) at CD4 counts > 350 cells/μL. It is hypothesized that earlier initiation of cART in asymptomatic and otherwise healthy individuals may lead to poorer adherence and subsequently higher rates of resistance development.

Methods

In a large cohort of HIV‐positive individuals, we investigated the emergence of new resistance mutations upon virological treatment failure according to the CD4 count at the initiation of cART.

Results

Of 7918 included individuals, 6514 (82.3%), 996 (12.6%) and 408 (5.2%) started cART with a CD4 count ≤ 350, 351–499 and ≥ 500 cells/μL, respectively. Virological rebound occurred while on cART in 488 (7.5%), 46 (4.6%) and 30 (7.4%) with a baseline CD4 count ≤ 350, 351–499 and ≥ 500 cells/μL, respectively. Only four (13.0%) individuals with a baseline CD4 count > 350 cells/μL in receipt of a resistance test at viral load rebound were found to have developed new resistance mutations. This compared to 107 (41.2%) of those with virological failure who had initiated cART with a CD4 count < 350 cells/μL.

Conclusions

We found no evidence of increased rates of resistance development when cART was initiated at CD4 counts above 350 cells/μL.

The effects of age on associations between markers of HIV progression and markers of metabolic function including albumin, haemoglobin and lipid concentrations

OBJECTIVES

We investigated whether age modified associations between markers of HIV progression, CD4 T lymphocyte count and HIV RNA viral load (VL), and the following markers of metabolic function: albumin, haemoglobin, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC).

METHODS

A retrospective analysis of data from the United Kingdom Collaborative HIV Cohort was carried out. Analyses were limited to antiretroviral-naïve subjects to focus on the impact of HIV disease itself. A total of 16670 subjects were included in the analysis. Multilevel linear regression models assessed associations between CD4 count/VL and each of the outcomes. Statistical tests for interactions assessed whether associations differed among age groups.

RESULTS

After adjustment for gender and ethnicity, there was evidence that lower CD4 count and higher VL were associated with lower TC, LDL-C, haemoglobin and albumin concentrations but higher triglyceride concentrations. Age modified associations between CD4 count and albumin (P < 0.001) and haemoglobin (P = 0.001), but not between CD4 count and HDL-C, LDL-C and TC, or VL and any outcome. Among participants aged < 30, 30-50 and > 50 years, a 50 cells/μL lower CD4 count correlated with a 2.4 [95% confidence interval (CI) 1.7-3.0], 3.6 (95% CI 3.2-4.0) and 5.1 (95% CI 4.0-6.1) g/L lower haemoglobin concentration and a 0.09 (95% CI 0.07-0.11), 0.12 (95% CI 0.11-0.13) and 0.16 (95% CI 0.13-0.19) g/L lower albumin concentration, respectively.

CONCLUSIONS

We present evidence that age modifies associations between CD4 count and plasma albumin and haemoglobin levels. A given reduction in CD4 count was associated with a greater reduction in haemoglobin and albumin concentrations among older people living with HIV. These findings increase our understanding of how the metabolic impact of HIV is influenced by age.

Predictive modeling of insulin release profile from cross-linked chitosan microspheres

Insulin-loaded microspheres composed of chitosan 3% (w/v), and loading 120 IU insulin were produced by emulsion cross-linking method. Cross-linking time was 5 h and glutaraldehyde 3.5% (v/v) was used as cross-linker. Swelling ratio studies were evaluated to predict release of insulin from chitosan microspheres. Bacitracin and sodium taurocholate were incorporated in the formulations as proteolytic enzyme inhibitor and absorption enhancer, respectively. In vitro insulin release studies were performed in phosphate buffer pH 7.4 and also in HCl pH 2 with and without trypsin. Activity of bacitracin was also evaluated. In vitro release showed a controlled profile up to 12 h and the formulation containing 0.15% (w/v) of bacitracin revealed a maximum biological activity of about 49.1 ± 4.1%. Mathematical modeling using Higuchi and Korsmeyer-Peppas suggested a non-Fickian diffusion as the mechanism of insulin release. Insulin-loaded chitosan microspheres for oral delivery showed to be an innovative and reliable delivery system to overcome conventional insulin therapy.

Thermo-sensitive gels containing lorazepam microspheres for intranasal brain targeting

Thermo-sensitive gels containing lorazepam microspheres were developed and characterized for intranasal brain targeting. Pluronics (PF-127 and PF-68) have been selected since they are thermo-reversible polymers with the property of forming a solution at low temperatures (4-5 °C), and a gel at body temperature (37 °C). This property makes them an interesting material to work with, especially in case of controlled release formulations. The present study focuses on the development of an intranasal formulation for lorazepam, as an alternative route of drug delivery to the brain. Direct transport of drugs to the brain circumventing the brain barrier, following intranasal administration, provides a unique feature and better option to target brain. The presence of mucoadhesive microspheres in the gel vehicle via nasal route can achieve a dual purpose of prolonged drug release and enhanced bioavailability. To optimise the microsphere formulation, Box Behnken design was employed by investigating the effect of three factors, polymer concentration (chitosan), emulsifier concentration (Span 80) and cross-linking agent (glutaraldehyde) on the response variable which is the mean particle size. The concentration of 21% PF-127 and 1% PF-68 were found to be promising gel vehicles. The results showed that the release rate followed a prolonged profile dispersion of the microspheres in the viscous media, in comparison to the microspheres alone. Histopathological studies proved that the optimised formulation does not produce any toxic effect on the microscopic structure of nasal mucosa.

Lymphoid organ cell culture system from Penaeus monodon (Fabricius) as a platform for white spot syndrome virus and shrimp immune-related gene expression

Shrimp cell lines are yet to be reported and this restricts the prospects of investigating the associated viral pathogens, especially white spot syndrome virus (WSSV). In this context, development of primary cell cultures from lymphoid organs was standardized. Poly-l-lysine-coated culture vessels enhanced growth of lymphoid cells, while the application of vertebrate growth factors did not, except insulin-like growth factor-1 (IGF-1). Susceptibility of the lymphoid cells to WSSV was confirmed by immunofluoresence assay using monoclonal antibody against the 28 kDa envelope protein of WSSV. Expression of viral and immune-related genes in WSSV-infected lymphoid cultures could be demonstrated by RT-PCR. This emphasizes the utility of lymphoid primary cell culture as a platform for research in virus-cell interaction, virus morphogenesis, up and downregulation of shrimp immune-related genes, and also for the discovery of novel drugs to combat WSSV in shrimp culture.

Cross-linked chitosan microspheres for oral delivery of insulin: Taguchi design and in vivo testing

Insulin-loaded chitosan microspheres were engineered by emulsion cross-linking method using glutaraldehyde as cross-linker. Taguchi orthogonal method was applied to optimize the production time and reduce the number of experiments required to obtain an optimized formulation. Three variables were evaluated, i.e. chitosan and glutaraldehyde concentrations, and cross-linking time at three levels. The dependent variables were the mean particle size and the encapsulation efficiency. The optimal formulation was obtained with chitosan 3% (w/v), glutaraldehyde 3.5% (v/v), and cross-linking time of 5h, characterized by microspheres with a mean particle size of 29.5 μm, and insulin encapsulation efficiency of 71.6±1.3%. In vivo studies were carried out using male Wistar albino rats, revealing a significant reduction in blood glucose level after administration of the optimized formulation, in comparison to a subcutaneous insulin injection. Chitosan microspheres were superior in terms of sustaining protein release over conventional insulin therapy.

Colon specific chitosan microspheres for chronotherapy of chronic stable angina

In the present work, chitosan microspheres with a mean diameter between 6.32 μm and 9.44 μm, were produced by emulsion cross-linking of chitosan, and tested for chronotherapy of chronic stable angina. Aiming at developing a suitable colon specific strategy, diltiazem hydrochloride (DTZ) was encapsulated in the microspheres, following Eudragit S-100 coating by solvent evaporation technique, exploiting the advantages of microbiological properties of chitosan and pH dependent solubility of Eudragit S-100. Different microsphere formulations were prepared varying the ratio DTZ:chitosan (1:2 to 1:10), stirring speed (1000-2000 rpm), and the concentration of emulsifier Span 80 (0.5-1.5% (w/v)). The effect of these variables on the particle size and encapsulation parameters (production yield (PY), loading capacity (LC), encapsulation efficiency (EE)) was evaluated to develop an optimized formulation. In vitro release study of non-coated chitosan microspheres in simulated gastrointestinal (GI) fluid exhibited a burst release pattern in the first hour, whereas Eudragit S-100 coating allowed producing systems of controlled release diffusion fitting to the Higuchi model, and thus suitable for colon-specific drug delivery. DSC analysis indicated that DTZ was dispersed within the microspheres matrix. Scanning electron microscopy revealed that the microspheres were spherical and had a smooth surface. Chitosan biodegradability was proven by the enhanced release rate of DTZ in presence of rat caecal contents.

Disseminated Rhodococcus equi infection in dromedary camels (Camelus dromedarius)

Rhodococcus (R). equi, a recognized pathogen in horses, is emerging as a human opportunistic pathogen, especially in immunocompromized people. It affects also New World camelids, but there are no reports of R. equi infection in Old World camelids yet. Four cases of disseminated R. equi infection in adult breeding dromedaries occurred at one camel farm near Dubai within 16 months of each other. At necropsy the lungs were diffusely consolidated with large caseous areas. Histology revealed severe suppurative to necrotising pneumonia with multiple encapsulated abscesses. Immunohistochemistry enabled the detection of 15- to 17-kDa antigens (VapA) of R. equi in the lung sections. High numbers of R. equi were isolated from the lung lesions as well as from liver, spleen and mediastinal lymph nodes, indicative of septicaemia. The isolated strains were PCR-positive for the specific virulence plasmid (VapA-Gen) of R. equi, indicating virulent strains and containing an 85-kb type I plasmid. This is the first report of disseminated R. equi infection in Old World camelids. Since adult camels in general do not suffer from bacterial caused pneumonia (except tuberculosis), this is a new emerging disease for camels.

Multiparticulate system for colon targeted delivery of ondansetron

Targeted delivery of drugs to colon has the potential for local treatment of a variety of colonic diseases. The main objective of the study was to develop a multiparticulate system containing chitosan microspheres for the colon targeted delivery of ondansetron for the treatment of irritable bowel syndrome. This work combines pH-dependent solubility of eudragit S-100 polymers and microbial degradability of chitosan polymers. Chitosan microspheres containing ondansetron were prepared by emulsion cross linking method. The effect of process variables like chitosan concentration, drug-polymer ratio, emulsifier concentration and stirring speed were studied on particle size and entrapment efficiency of chitosan microspheres. In vitro drug release studies in simulated gastro intestinal fluids showed a burst drug release pattern in the initial hour necessitating microencapsulation around the chitosan microspheres. The optimized formulation was then subjected to microencapsulation with eudragit S-100 by solvent evaporation technique. The effect of different coat/core ratio on particle size, drug entrapment efficiency and in vitro drug release were studied. Formulation which contain 1:10 core/coat ratio released lesser amount of drug in the upper gastro intestinal conditions and so selected as best formulation and then subjected to in vitro drug release studies in presence of rat ceacal contents to assess biodegradability of chitosan microspheres in colon. In order to study the drug release mechanism in vitro drug release data was fitted into various kinetic models. Analysis of regression values suggested that the possible drug release mechanism was Peppas model.

In vitro susceptibility of viridans streptococci to leaf extracts of Mangifera Indica

The susceptibility of Viridans streptococci to leaf extracts of Mangifera indica was studied on 53 clinical isolates from 39 patients. All the isolates were found to be susceptible to both water and methanol extract of M. indica leaves. Minimum inhibitory concentration (MIC) of methanol extract for all isolates were <50 mg/mL and MIC of water extract for all isolates were <200 mg/mL. Methanol extract was found to have better action against Viridans streptococci than water extract.

Plant diversity enhances ecosystem responses to elevated CO2 and nitrogen deposition

Human actions are causing declines in plant biodiversity, increases in atmospheric CO2 concentrations and increases in nitrogen deposition; however, the interactive effects of these factors on ecosystem processes are unknown. Reduced biodiversity has raised numerous concerns, including the possibility that ecosystem functioning may be affected negatively, which might be particularly important in the face of other global changes. Here we present results of a grassland field experiment in Minnesota, USA, that tests the hypothesis that plant diversity and composition influence the enhancement of biomass and carbon acquisition in ecosystems subjected to elevated atmospheric CO2 concentrations and nitrogen deposition. The study experimentally controlled plant diversity (1, 4, 9 or 16 species), soil nitrogen (unamended versus deposition of 4 g of nitrogen per m2 per yr) and atmospheric CO2 concentrations using free-air CO2 enrichment (ambient, 368 micromol mol-1, versus elevated, 560 micromol mol-1). We found that the enhanced biomass accumulation in response to elevated levels of CO2 or nitrogen, or their combination, is less in species-poor than in species-rich assemblages.