From growth inhibition to ultrastructural changes: Toxicological assessment of lambda cyhalothrin and fosetyl aluminium against Bacillus subtilis and Pseudomonas aeruginosa.

In modern agricultural practices, agrochemicals and pesticides play an important role in protecting the crops from pests and elevating agricultural productivity. This strategic utilization is essential to meet global food demand due to the relentless growth of the world's population. However, the indiscriminate application of these substances may result in environmental hazards and directly affect the soil microorganisms and crop production. Considering this, an in vitro study was carried out to evaluate the pesticides' effects i.e. lambda cyhalothrin (insecticide) and fosetyl aluminum (fungicide) at lower, recommended, and higher doses on growth behavior, enzymatic profile, total soluble protein production, and lipid peroxidation of bacterial specimens (Pseudomonas aeruginosa and Bacillus subtilis). The experimental findings demonstrated a concentration-dependent decrease in growth of both tested bacteria, when exposed to fosetyl aluminium concentrations exceeding the recommended dose. This decline was statistically significant (p < 0.000). However, lambda cyhalothrin at three times of recommended dose induces 10% increase in growth of Pseudomonas aeruginosa (P. aeruginosa) and 76.8% decrease in growth of Bacillus subtilis (B. subtilis) respectively as compared to control. These results showed the stimulatory effect of lambda cyhalothrin on P. aeruginosa and inhibitory effect on B. subtilis. Pesticides induced notable alterations in biomarker enzymatic assays and other parameters related to oxidative stress among bacterial strains, resulting in increased oxidative stress and membrane permeability. Generally, the maximum toxicity of both (P. aeruginosa and B. subtilis) was shown by fosetyl aluminium, at three times of recommended dose. Fosetyl aluminium induced morphological changes like cellular cracking, reduced viability, aberrant margins and more damage in both bacterial strains as compared to lambda cyhalothrin when observed under scanning electron microscope (SEM). Conclusively the, present study provide an insights into a mechanistic approach of pyrethroid insecticide and phosphonite fungicide induced cellular toxicity towards bacteria.

Community-acquired meningoencephalitis due to concomitant infection caused by Naegleria fowleri and Streptococcus pneumoniae from Karachi, Pakistan: A Case Report.

Naegleria fowleri causes acute fatal primary amoebic meningoencephalitis in adults and children with a history of exposure to aquatic activities. However, several cases of Primary Amoebic Meningoencephalitis (PAM) have been reported from Karachi with no history of aquatic recreational activities suggesting the presence of N. fowleri in domestic water. This study reports a case of co-infection of N. fowleri with Streptococcus pneumoniae in an elderly hypertensive male.

Comparison of dried blood spots with conventional blood sampling for diagnosis of hepatitis b & c through serological and molecular technique; a pilot study.

OBJECTIVE: To compare the sensitivity and specificity of dried blood spot with conventional blood sampling for serological and molecular testing of hepatitis B and C viruses. METHODS: The case-control study was conducted at the Pakistan Health Research Council Specialised Centre for Gastroenterology and Hepatology, Karachi, from May,2015 to April,2016 and comprised patients who were hepatitis B surface antigen-positive (group 1), anti-hepatitis C virus positive (group 2), hepatitis B virus deoxyribonucleic acid-positive (group 3), and hepatitis C virus ribonucleic acid-positive (group 4). A group of controls had healthy subjects negative for both hepatitis B and C viruses. Blood samples were collected using the conventional as well as the dried blood spot method using finger prick. Relevant tests were run for each subject using both the samples at baseline and after 3 and 6 months of storage. Receiver operative characteristic curve was plotted to determine the ideal cut-off points for dried blood spot testing and corresponding sensitivity and specificity. Data was analysed using SPSS 19. RESULTS: Of the 100 subjects, there were 20(20%) in each of the four patient groups and 20(20%) in the control group. Sensitivity of dried blood spot method was 95.2%, 95%, 80% and 70% for groups 2, 1, 4 and 3 respectively when tested within a week of sampling. Specificity was 100% for all the four groups. There was a significant correlation of the two methods for all the four parameters tested (p<0.01). CONCLUSIONS: Dried blood spot sampling correlated well with the conventional blood sampling method for serological and molecular testing.

Report - Colonization rates and immune status of children against Streptococcus pneumoniae before the introduction of pneumococcal conjugate vaccine.

Pneumococcal infections contribute to high morbidity and mortality in Pakistan. Pneumococcal colonization rates and immune status of children before and after vaccination can serve as an important indicator to determine the success of immunization program. Aim of this study was to determine the pneumococcal colonization rate and immune status of children (<3-years) before the introduction of Pneumococcal immunization in EPI program. A cross sectional study of 3-months duration was conducted in collaboration with EPI Centre of NICH, Karachi. A total of 192 healthy children aged 3-months to 3-years were included in the study. Children with chronic or recurrent pulmonary disease were excluded. Demographic data and presence of any risks for pneumococcal colonization or immunity was recorded. Nasopharyngeal swabs were collected to determine the presence of S. pneumoniae and sensitivity pattern of the isolates. Blood samples were collected to determine immune status of these children. Sixty (31%) children were found to carry S. pneumoniae in their nasopharynx. Resistance to cotrimoxazole, erythromycin, chloramphenicol, penicillin and vancomycin was 100%, 30%, 25%, 22% and 0% respectively. Mean anti-PCP titre of children was 23.3mg/L. Mean anti-PCP titre in children who had previously suffered from RTI was significantly increased (p-value 0.039). This study may serve as baseline report for evaluating the success of pneumococcal immunization in future. A significant drop in nasopharyngeal colonization rates post vaccination would depict the success of pneumococcal immunization.

Weak two-photon absorption applied to the rapid prototyping of cell scaffolds.

Two-photon polymerization (TPP) has been employed to generate deep structures using the biocompatible and optically transparent monomer ethoxylated bisphenol A dimethacrylate (EO=6) (EBPADMA) and 4, 4'-Bis(diethylamino)benzophenon as the photoinitiator. The two-photon absorption cross section of the initiator was measured to be 1 GM (1 GM=1×10(-50) cm(4) s photon(-1)) in EBPADMA. Here we have explored a weak absorption regime whereby deep structures (∼300 µm) can be generated in a single pass. This allows rapid fabrication of structures suitable for cell scaffolds where the length scales are small, ∼10 µm, but are required over long ranges, ∼cm. The dependence of the TPP properties on the writing power, speed, exposure time and NA, of the focusing lens were studied in detail. Diffraction calculations for the focusing optics employed show that spherical aberration plays a significant role in determining the feature sizes achieved.

Emerging trends of antimicrobial resistance in Helicobacter pylori isolates obtained from Pakistani patients: The need for consideration of amoxicillin and clarithromycin.

OBJECTIVE: To present antimicrobial susceptibility profile of helicobacter pylori isolated from gastric biopsies of dyspeptic patients. METHODS: The cross-sectional study was conducted from March 2008 to May 2013 at the Jinnah Postgraduate Medical Centre (JPMC), Karachi, and comprised patients with suspected peptic ulcer disease who underwent upper gastrointestinal endoscopy. Multiple gastric antral biopsies were taken. One sample was imbedded in the Campylobacter-like organism test, while other biopsies were processed for culture and confirmed on polymerase chain reaction. Isolates were subjected to antimicrobial susceptibility testing and minimum inhibitory concentrations of antimicrobial agents were estimated by Epsilometer test. SPSS 21 was used for statistical analysis. RESULTS: Of the 889 samples available, 254(28.6%) were positive after campylo-like organism test, of them, 92(36.2%) isolates were cultured. Susceptibility test showed 90(97.8%) resistance to metronidazole, 25(30.1%) ofloxacin, 6(16.2%) levofloxacin, 14(15.2%) furazolidone, 5(5.4%) clarithromycin, 4(4.3%) tetracycline and 2(2.2%) isolates showed resistance to amoxicillin. Resistance to more than one drug was observed in 37(40.2%) isolates. CONCLUSIONS: Low clarithromycin resistance was surprising since Pakistan is considered a hot bed of drug-resistant bacteria.

Thyroid dysfunction in Khyber Pakhtunkhwa, Pakistan.

OBJECTIVES: The objective of this research was to elucidate some of the major relation of thyroid dysfunctions, keeping in view the various selected demographic details of included patients. METHODS: This study was approved by the ethical committee of Post Graduate Medical Institute (PGMI) Hayatabad Medical Complex Peshawar, and was conducted in the Institute of Radioactive Nuclear Medicine (IRNUM) Peshawar. The blood samples were collected, followed by their analysis for triiodothyronine (T3), tetraiodothyronine (T4) and thyroid stimulating hormone (TSH). RESULTS: The results obtained regarding the demographical aspects of the patients revealed that female gender has categorically significantly high percentage of occurrence of thyroid abnormality as compared to male gender (75.8% vs. 24.2%). Results regarding locality distribution of the patients depicted that majority of those belonged to the local population of Peshawar and Charsadda region. CONCLUSION: In Pakistan especially Khyber Pakhtunkwa (KPK), thyroid diseases are more common in females as compared to males. The most probable causes could be lactation and pregnancy.

Femtosecond pulsed laser ablation of polyimide at oblique angles for medical applications.

We report the ablation results for surface modification of polyimide Kapton HN foils using ultrashort femtosecond laser pulses. The modification threshold fluences for 75 µm thick films of polyimide were determined at different incident angles (0°, 20°, 30°, 45°, and 50°) for vertical and horizontal diameters. Ablation at oblique angles was investigated as such interactions are found during laser procedures with the eye that require scanning of the beam and are very important to know for the treatment of various eye diseases. Polyimide, in this study, was considered as a model for corneal sculpting. Use of ultrashort femtosecond laser pulses for high-precision patterning of the sample, without thermal damage to the surroundings, has been investigated. The relationship between the incidence angle with ablation threshold fluence, threshold energy, and beam radius are described. Also, threshold energies and threshold fluences for different thicknesses of polyimide were investigated.

Study of the two-photon excitation of photoinitiator in various solvents, and the two-photon polymerization process.

In this study, the two-photon absorption excited fluorescence of the photosensitizer 4,4'-Bis(diethylamino)benzophenonin in different solvents is investigated by using mode-locked Ti:sapphire excitation having a wavelength of 800 nm with pulse duration of 150 fs at the rate of 1 kHz. The fluorescence signals excited by wavelengths of 800 and 400 nm have been compared. Contribution of these cross-section measurements for the two-photon polymerization processes is also reported.

Determination of two-photon absorption cross sections of photosensitizers and its implications for two-photon polymerization.

We report two-photon absorption cross sections and two-photon excited fluorescence of the photosensitizer 4,4'-Bis(diethylamino)benzophenon and thioxanthone using a femtosecond laser delivering pulses of wavelength 800 nm and 150 fs duration at rates of 1 kHz. Values for the two-photon absorption cross section are derived by comparing the fluorescence signals excited by wavelengths of 800 and 400 nm using a second-harmonic generator. Fluorophore fluorescence intensities dependence with quadratic illumination laser power showed no significant deviation from the two-photon absorption process. Implications of these cross-section measurements for two-photon polymerization are discussed.

Is chlorhexidine-gluconate superior than Povidone-Iodine in preventing surgical site infections? A multicenter study.

OBJECTIVE: To compare the efficacy of povidone-iodine and chlorhexidine gluconate scrubs in preventing surgical site infections. METHODS: The randomised controlled clinical trial was conducted from May 2012 to April 2013 in two public-sector hospitals of Pakistan; one each in Karachi and Islamabad. Patients undergoing clean or clean contaminated surgeries were included and were randomly assigned to one of the two groups: group I comprised patients whose skin was preoperatively disinfected using 10% povidone-iodine, and in group II by 2% chlorhexidine gluconate in 70% alcohol. A predesigned proforma was filled for all patients to record demographic data, diagnosis, surgical procedure and antibiotic used. Patients in both groups were followed up for one month postoperatively to monitor any signs of surgical site infections. SPSS 16 was used for statistical analysis. RESULTS: Of the 388 patients from the two hospitals, 220(57%) were in group I and 168(43%) were in group II. Surgical site infection was observed in 22(10%) cases in group I and 12(7.1%) in group II (p=0.324). Pseudomonas aeruginosa (23.5%) was the predominant pathogen associated with surgical site infections followed by Staphylococcus aureus (17.6%). CONCLUSIONS: Chlorhexidine gluconate was associated with lower infection rates compared to povidone-iodine; but it was not statistically significant.

Response to Recombinant Human Growth Hormone (rhGH) Therapy in Children with Growth Hormone Deficiency.

OBJECTIVE: To determine the auxological response to recombinant human growth hormone (rhGH) therapy in children with growth hormone deficiency (GHD) presenting at the National Institute of Child Health, Karachi, Pakistan. STUDY DESIGN:  Observational study. Place and Duration of the Study: Department of Paediatric Endocrinology, National Institute of Child Health, Karachi, Pakistan, from January 2022 to December 2023. METHODOLOGY:  All pre-pubertal children with short stature aged 3-12 years diagnosed with GHD and who were prescribed rhGH therapy were included in the study. Children with any other underlying reason for short stature or any other comorbidity were excluded. Patients' demographics and baseline growth parameters were recorded in a pre-designed proforma. Patients were then followed up every three months till one year. Response to rhGH therapy was evaluated through comparison of growth parameters before and after one year of therapy. RESULTS: A total of 90 children including 47 (52.2%) males and 43 (47.8%) females with GHD were enrolled. Mean age of these patients was 7.92 ± 2.647 years. A statistically significant change in height (SD), Weight (SD), and BMI (SD) was observed before and after one year of therapy (p <0.001). Response to therapy in terms of height did not differ significantly with respect to gender (p = 0.955) or stimulated growth hormone levels (p = 0.911). However, response to rhGH therapy was significantly better in terms of increase in height, weight, and BMI in patients presenting earlier i.e. at age ≤8 years. CONCLUSION: Recombinant human growth hormone therapy was effective in children with short stature to achieve desirable growth. Children diagnosed and treated at a younger age (≤8years) achieve better height outcomes as compared to those presenting late. KEY WORDS:  Short stature, Growth hormone deficiency, Recombinant human growth hormone.

Seasonal Trends with the Comparison of Venous and Capillary Blood for Diagnosis of Malaria among Children in Karachi, Pakistan.

Background: More than 250 million people are infected by malaria parasites annually while around one million children less than 5 years of age die every year due to malaria. We aimed to assess the seasonal trends and usefulness of capillary and venous blood for rapid diagnosis of malaria. Methods: This cross-sectional study of 18 months duration was conducted at the National Institute of Child Health (NICH), Karachi. All patients reporting fever as chief complaint were recruited as study subjects. A semi-structured questionnaire was used to collect demographic information, presenting complaints, awareness of caregivers regarding malaria, preventive measures and history of malaria fever. Three ml Venous (2-3ml) as well as peripheral blood (3-4 drops) samples of all patients were collected for microscopy and rapid diagnostic tests (RDTs). Results: Out of total 477 patients with fever Venous and Capillary Blood RDTs methods detected 33(6.9%) and 30(6.3%) as the malaria positive while Venous and Capillary Blood Microscopy detected 30(6.1%) and 32(6.7%) cases respectively. Plasmodium Vivax infection was the most prevalent (87.9%) and majority (39.39%) of the cases occurred in the quarter, July to September. Conclusion: July to September is the peak season for malaria and P. Vivax (87.9%) is the predominant strain in Karachi. Venous and capillary blood are equally useful for malaria diagnosis however, convenience and less invasiveness may justify the preference of capillary blood over venous blood for early diagnosis of malaria.

Clinical Presentation, Diagnostic Approach, Laparoscopic Evaluation and Treatment of Impalpable Testis.

OBJECTIVE: To find out the clinical presentation, utility of ultrasound for diagnosis, laparoscopic findings and treatment for clinically impalpable testis. STUDY DESIGN: Cross-sectional study. PLACE AND DURATION OF STUDY: Department of Paediatric Surgery, National Institute of Child Health, Jinnah Sindh Medical University Karachi, from September 2019 to April 2020. METHODOLOGY: Patients with clinically impalpable testis were included. Ultrasound of inguinal region was done to locate testis. Presence of testis and its position was confirmed at laparoscopy and surgical procedure done according to the findings. Data was stratified according to the age and Chi-square test and Student t-test were applied to find out statistical significance among different variables in children below and above five years of age. A p <0.05 was taken as significant. RESULTS: Ninety-one patients with 113 testes were included. The median age of the children was 48 months. Sixty-nine (75.8%) patients had unilateral undescended testis and 22 (24.2%) bilateral undescended testes. Fifty-three (58.2%) patients were less than five years of age. On ultrasound, testis was found near deep ring in 23 (25.3%) patients. At laparoscopy, 74 (81.3%) testes were found within the abdominal cavity. In 7 (7.7%) patients, only nubbin of tissue was identified and removed. The first stage of Fowler Stephen procedure was done in the majority of the patients. There was statistically no significant difference following stratification in relation to laterality and position of undescended testis (p = 0.556 and p = 0.846, respectively). However, mean size of the testis was found statistically significant (p = 0.032). CONCLUSIONS: Most of the patients were above five years of age. Ultrasound helped in identifying low-lying intra-abdominal testis in more than 80% of patients. Laparoscopy was helpful in further defining the position of the testis and selection of surgical procedure. KEY WORDS: Undescended testis, Cryptorchidism, Laparoscopy, Orchiopexy.

Correlation Of Glomerular Filtration Rate (Gfr) Estimation Formulae With Measured Gfr In Pediatric Oncology Patients.

Background: In patients with malignancy accurate assessment of renal function is important for administration of chemotherapeutic medicines. Measurement of GFR by inulin, EDTA clearance, iohexol and 24 hrs urinary creatinine clearance (Crcl) is cumbersome so creatinine based GFR formulas have been developed for assessment of kidney function and there are variety of GFR formulas available for clinical use. Objective was to determine the correlation of estimated GFR by creatinine-based estimation formulae with measured GFR by 24-hours creatinine clearance. Methods: A cross sectional study was conducted in which all patients who underwent measured GFR (mGFR) assessment at Oncology Unit of NICH between 1st January to 31st December 2019 were enrolled in the study. Estimated Glomerular filtration rate (eGFR) of all these patients was calculated by three formulae Original Schwartz (OS), Updated Schwartz (US) and simple height independent equation (SHID). Correlation was made with mGFR by Crcl taken as gold standard using Pearson's correlation and Linear regression analysis. Bland Altman analysis was also done to see the agreement between eGFR with mGFR. Results: Total sixty (60) patients were enrolled with mean age of 8.2±3.6 years. All three eGFR formulae exhibited a statistically significant positive correlation with mGFR (p-value <0.01). Linear regression analysis also showed a statistically significant relation between mGFR and eGFRs however, the developed regression models for all three formulae showed a low R2 values. Bland-altman analysis revealed that useful level of agreement does not exist between mGFR and eGFR by OS however, SHID and US were found to be in agreement with mGFR by Crcl. Conclusion: SHID and US equations give a good estimate of GFR and may be used in children with malignancies to estimate GFR.

Genetic diversity in enhancer II region of HBV genotype D and its association with advanced liver diseases.

BACKGROUND: Hepatitis B Virus (HBV) is one of the most common human infectious agents, and the mutations in its genome may cause chronic hepatitis (CH), liver cirrhosis (LC), and hepatocellular carcinoma (HCC). This study was designed to characterize the enhancer-II (Enh-II) region of X gene in HBV positive patients to assess the association of such mutations with CH, LC, and HCC. METHODS: HBV positive samples (N = 200) with patients' demographic and clinical data were collected from different regions of Khyber Pakhtunkhwa (KP), Pakistan. The Enh-II region of the HBx gene was sequenced and zanalyzed for polymorphism associated with advanced liver disease. Univariate and logistic regression analyses were performed to evaluate potent mutations associated with a risk for LC and HCC. RESULTS: HBV Enh-II region sequences analysis revealed 25 different mutations. The highest frequency of mutations S101F (62.2%), A102V/R/G/I (56.25%), M103L/A (68.75%)were found in HCC, followed in LC and CH patients as 57.1%, 42.8%, 28.52% 16%, 15.2% and 18.4% respectively. H94 deletion in the α-box of the Enh-II region, associated with a high risk of HCC was found in half of the HCC patients. This deletion was present in 28.5% of LC and 6.5% of CH patients. Importantly, the high frequency of some notable mutations such as E109A/Y, A110S/K, Y111D/E, and F112L was first time reported in the entire study population. The frequencies of these mutations were high in HCC (43.75%, 37.5%, 50% and 43.75% respectively) as compared to LC (14.28%, 14.28%, 28.2% and 42.8%) and CH patients (12.8%, 15.2%, 16.8% and 16% respectively). CONCLUSION: Mutations associated with LC and HCC are prevalent in the Enh-II region in Pakistani HBV isolates. The mutations found are alarming in CH patients as these may progress to LC and HCC in a large number of patients.

T3 is linked to stress-associated reduction of prolactin in lactating women.

The relationship between stress responses and lactation is bidirectional. Breastfeeding confers many benefits to maternal health, including attenuated hypothalamic-pituitary-adrenal axis responsiveness to stress. However, increased stress burden can impair lactation. The mechanisms that underlie these relationships are poorly understood. The present study aimed to compare breastfeeding habits, as well as subjective and objective measures of stress, in employed and non-employed lactating women and assess the relationships between these measures and prolactin (PRL), thyroid hormones (thyroid-stimulating hormone, triiodothyronine [T3] and thyroxine), vasopressin and cortisol levels. A dexamethasone suppression test was also administered to determine the sensitivity of the hypothalamic-pituitary-adrenal axis to negative-feedback. We report that lactating employed women had lower breastfeeding rates and lower PRL than lactating non-employed women. They also had a significantly higher stress burden, indicated by elevations in blood pressure and evening cortisol, relative to lactating non-employed women. In regression analyses that controlled for feeding modality and breastfeeding duration, we found these factors differentially affected PRL in the two groups and there were significant differences in PRL across groups that were not accounted for by these factors. A mediation regression analysis suggested that group differences in PRL were best explained by differences in T3 and income levels, rather than breastfeeding duration or other variables. Our data fit a speculative model in which elevated maternal stress increases cortisol, which suppresses T3, leading to decreased PRL. The decreases in PRL are associated with higher rates of bottlefeeding, which may further contribute to decreased PRL.

Detection of active mycobacterium tuberculosis at 6th month exit among declared successfully treated cases in Pakistan.

OBJECTIVES: Tuberculosis (TB) is a significant public health concern, and the basis of successful anti-tuberculosis treatment (ATT) rests on the complete eradication of live bacilli from a patient. This study was conducted to detect the live TB bacilli in Lowenstein Jensen culture media among exit cases of TB who were declared successfully treated, either cured or treatment completed. METHODS: This cross-sectional study was conducted across Pakistan. Fifty-eight active TB DOTS centers were selected. The sample size of 3355 TB cases were equally distributed in all DOTS facilities. A detailed questionnaire was developed to record the information from TB DOTS and patients. After successful treatment, the sputum was taken from TB cases and examined to detect live bacilli on L-J culture. RESULTS: A total of 3355 TB cases were enrolled in the study. The male to female proportion was 1704(50.9%) and 1651(49.2%). Initially, 1993(59.4%) cases were cured, and 1362(40.6%) were declared as treatment completed cases. At exit, 324(9.65%) cases were again ZN smear-positive, and 328(9.77%) were positive on L-J culture, after being declared successfully treated for TB. CONCLUSIONS: To eradicate live TB bacilli, all TB cases should be subjected to L-J culture at the end of ATT.

Infection control practices in blood banks of Pakistan.

BACKGROUND: Implementation of infection control standards in blood banks is important to prevent transmission of blood-borne infections such as HIV, hepatitis B and Hepatitis C. No study from Pakistan evaluated the infection control practices in the blood banks of Pakistan. AIMS: This study aimed to evaluate infection control practices with reference to safe blood supply, staff safety and waste disposal practices in blood banks of Karachi, Pakistan. METHODS: This was a cross-sectional study. Infection control practices of all blood banks working in Karachi were determined through a structured questionnaire followed by an educational intervention. Mean scores for overall infection control practices and specific practices regarding safe blood supply, staff safety and waste disposal were calculated and compared with different factors using statistical tools. RESULTS: Patient safety scores of 49 (92.5%) blood banks were within the satisfactory range but staff safety and waste disposal scores of only 26 (49.1%) and 4 (7.5%) blood banks were satisfactory. Significantly lower infection control (IC) scores were observed for stand-alone blood banks and those working in the absence of a haematologist (P-value < 0.001). Availability of written standard operating procedures (SOPs) and IC guidelines correlated positively (P-value < 0.001) with mean IC scores. CONCLUSIONS: Blood banks in Karachi lack implementation of IC standards particularly with reference to staff safety and waste management and disposal. Sindh blood transfusion authority (SBTA) should take measures to increase IC compliance within blood banks.