Sensitive and highly selective colorimetric biosensing of vitamin-C and vitamin-B1 by flavoring agent-based silver nanoparticles.

A sensitive scheme was established for the detection of vitamin C (Ascorbic acid) and vitamin B1 (Thiamin HCl) using Maltol capped AgNPs (McAgNPs) as colorimetric sensor. The designed scheme showed an instant alteration in color from yellow to orange and green for vitamin-C and vitamin B1 sequentially. The probe was sensitive in a concentration range of (0-1 µM) with limit of detection 0.064 and 0.038 µM for vitamin C and vitamin B1 sequentially. The interaction mechanism between vitamin C and vitamin B1 and McAgNPs was evaluated by visible spectroscopy, FTIR, and AFM. Vitamin C attaches on the surface of nanoparticles by C=O group, while OH, C-S-C, and NH2 groups are involved in the binding of vitamin B1 with McAgNPs. The Vit-C/Vit-B1-McAgNPs complexes were stable over a wide range of pHs. The size of McAgNPs increased after the interaction of vitamin C/vitamin B1 from 30-40 nm to 500 and 400 nm sequentially. The scheme was successfully applied for the detection of vitamin C and vitamin B1 in urine, plasma, water, and commercial pharmaceutical tablets with good recoveries. The scheme was ascertained to be more sensitive than many other formerly described schemes.

Seroprevalence of anti-SARS-CoV-2 antibodies in residents of Karachi-challenges in acquiring herd immunity for COVID 19.

BACKGROUND: The recent pandemic by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global emergency. There is large number of asymptomatic cases of SARS-CoV-2 that are not reported. Hence, serological evidence of SARS-CoV2 antibodies is warranted for a better estimation of the actual number of infected patients to limit the disease spread and to get an idea of herd immunity. METHODS: This is a cross-sectional study conducted from May 2020 to July 2020 at National Institute of Blood Diseases at Pakistan. The study includes healthcare workers (HCWs), community and industrial workers. The anti-SARS-CoV-2 test was performed by electrochemiluminescence immunoassay analyzer. RESULTS: A total of 1675 samples have been received from three groups of population. The percentage positivity for industrial employees is high (50.3%) for HCW (13.2%) and community population (34%).Total percentage for positive antibodies result is ~36%. CONCLUSION: Our seroprevalence is 36%, which still far from herd immunity that needs to be at least 60-70% in population. If we consider acquiring 60% seroprevalence in next few months, then herd immunity is not far from reality, provided the antibodies did not decline with time. Although the current study is based on a small sample of participants, the findings suggest a study with larger population to implement stronger and targeted interventions.

Mycobacterium mucogenicum meningitis due to external ventricular drain.

INTRODUCTION: Mycobacterium mucogenicum is a rare non-tuberculous organism associated with catheter-related infections when pathogenic in humans. We present the first case of an external ventricular drain (EVD)-associated M. mucogenicum meningitis. CASE PRESENTATION: A 55-year-old woman had EVD placement for obstructive hydrocephalus following traumatic subarachnoid haemorrhage. Cerebrospinal fluid (CSF) was obtained 5 days later for fever and neurological changes. M. mucogenicum was ultimately isolated from the CSF and the patient was placed on appropriate antibiotics. Her management included replacement of the EVD and a prolonged course of anti-mycobacterial antibiotics. CSF findings showed her response to therapy and neurological exam improved after 6 weeks. CONCLUSION: M. mucogenicum infections are very rare and existing reports indicate that it may be a device- or catheter-related pathogen. This microorganism has not been previously associated with an EVD. Ours may be the first documented report of EVD-related M. mucogenicum infection.

Incidence of Venous Thromboembolism in Critically Ill Coronavirus Disease 2019 Patients Receiving Prophylactic Anticoagulation.

OBJECTIVES: One of the defining features of the novel coronavirus disease 2019 infection has been high rates of venous thromboses. The present study aimed to describe the prevalence of venous thromboembolism in critically ill patients receiving different regimens of prophylactic anticoagulation. DESIGN: Single-center retrospective review using data from patients with confirmed severe acute respiratory syndrome coronavirus 2 requiring intubation. SETTING: Tertiary-care center in Indianapolis, IN, United States. PATIENTS: Patients hospitalized at international units Health Methodist Hospital with severe acute respiratory syndrome coronavirus 2 requiring intubation between March 23, 2020, and April 8, 2020, who underwent ultrasound evaluation for venous thrombosis. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 45 patients were included. Nineteen of 45 patients (42.2%) were found to have deep venous thrombosis. Patients found to have deep venous thrombosis had no difference in time to intubation (p = 0.97) but underwent ultrasound earlier in their hospital course (p = 0.02). Sequential Organ Failure Assessment scores were similar between the groups on day of intubation and day of ultrasound (p = 0.44 and p = 0.07, respectively). D-dimers were markedly higher in patients with deep venous thrombosis, both for maximum value and value on day of ultrasound (p < 0.01 for both). Choice of prophylactic regimen was not related to presence of deep venous thrombosis (p = 0.35). Ultrasound evaluation is recommended if D-dimer is greater than 2,000 ng/mL (sensitivity 95%, specificity 46%) and empiric anticoagulation considered if D-dimer is greater than 5,500 ng/mL (sensitivity 53%, specificity 88%). CONCLUSIONS: Deep venous thrombosis is very common in critically ill patients with coronavirus disease 2019. There was no difference in incidence of deep venous thrombosis among different pharmacologic prophylaxis regimens, although our analysis is limited by small sample size. D-dimer values are elevated in the majority of these patients, but there may be thresholds at which screening ultrasound or even empiric systemic anticoagulation is indicated.

Synthesis and characterization of maltol capped silver nanoparticles and their potential application as an antimicrobial agent and colorimetric sensor for cysteine.

Maltol capped silver nanoparticles (McAgNPs) were synthesized using maltol (3-hydroxy-2-methyl-4-pyrone) as reducing and capping agent. McAgNPs were characterized by Visible and FTIR (Fourier transform infrared) spectroscopy, dynamic light scattering (DLS), and atomic force microscopy (AFM). Bright yellow color McAgNPs showed surface plasmon resonance (SPR) band at 436 nm, spherical shape and the average size between 35 to 50 nm. McAgNPs revealed higher stability against varying storage time, temperature, pH and salt concentrations. McAgNPs were successfully utilized for the selective and highly sensitive colorimetric detection of cysteine (Cys). Addition of Cys in a solution of McAgNPs, resulted a rapid change in color from yellow to orange because of the formation of nanoaggregates as confirmed by Visible/FTIR spectroscopy, DLS, and AFM studies. The estimated limit of detection (0.043 µM) was found to be more sensitive than previously reported other optical methods. The practical applicability of probe was also established by spiking the known concentrations of Cys in biological (blood plasma and urine) and environmental (tap and lake water) samples with significant recovery rates (92-104.6%). Despite being nontoxic to various tested cell lines, McAgNPs demonstrated potent antimicrobial, antibiofilm, and biofilm eradicating activities, thus potentially valuable in diagnostics and/or the synthesis of other nanocomposite material for broader applications.

Synthesis and sensitive detection of doxycycline with sodium bis 2-ethylhexylsulfosuccinate based silver nanoparticle.

The monitoring of residual antibiotics in the environment has gained a significant importance for the effective control, because of the high risk to human health. A simple strategy was designed for the green synthesis and detection of doxycycline (Dox) by using anionic surfactant sodium bis 2-ethylhexylsulfosuccinate based silver nanoparticles (AOT-AgNPs). The chemical reduction and capping of Ag+1 ions was achieved by sulfonyl and carbonyl functional groups of AOT molecule. The AOT-AgNPs were found to have excellent stability at variable environmental parameters (i.e. temperature, storage period, salt concentration and pH) possibly due to the strong emulsifying nature of the surfactant. Mechanism of interaction between the AOT-AgNPs and Dox was established with UV/visible, Fourier transform infrared (FTIR) spectroscopy, Atomic force microscopy (AFM) and Dynamic light scattering (DLS) techniques, which suggests the interaction via aggregates formation. The synthesize probe could detect the Dox within 15 min over a wide range of concentrations from 0.1 to 140µM with limit of detection (LOD) of 0.2 µM. As proof of strategy, we have illustrated that the AOT-AgNPs also detect Dox in biological and environmental samples with negligible interference and very significant recovery rates. Moreover, non-toxic nature against various tested cell lines (i.e. normal mouse fibroblast (NIH-3 T3) and cancerous non-small lung carcinoma (NCI-H460)) and significant antimicrobial, antibiofilm and biofilm eradicating potential of AOT-AgNPs were provide ideal nanomaterial for further applications.

Duplication cyst of the pylorus: a rare cause of gastric outlet obstruction.

Alimentary tract duplications are a rare congenital malformation. They can present with varied symptoms owing to the locality of the duplication, along the gastrointestinal tract. Out of these duplications, the ones along the pylorus are the most rare. These are usually only diagnosed intraoperatively, as it is not a common differential on imaging due to its rarity. In lieu of the literature currently available, pyloric duplication cyst can present anytime from 1 week of age to 5 years, with some cases being detected antenatally due to the prevalence of regular antenatal scanning. Surgery remains the main stay of treatment with the goal of complete excision of the cyst and complete removal of the cyst mucosal lining. We report the case of a 5-year-old girl, which to our knowledge is the first ever reported case from Karachi, Pakistan.

Ameliorating effect of Allium Sativum on high-fat diet induced fatty liver in albino rats.

OBJECTIVE: To assess the hepatoprotective effect provided by fresh garlic on fatty liver induced by high-fat diet. METHODS: This experimental study was carried out at BMSI, JPMC from October to November 2008. Thirty adult albino rats, 200-240 gram weight, were divided into three groups. Group A received control diet, Group B received high-fat diet (20 mg butter/100 gm diet) and Group C received high-fat diet with fresh garlic (20 mg butter with 6 gm fresh garlic/100 gm diet). The groups were further divided on the basis of duration of treatment, four weeks and eight weeks respectively. The rats were sacrificed, liver removed, weighed and relative liver weight calculated. Hepatic tissue was processed and tissue slides stained with haematoxylin and eosin. RESULTS: There was significant increase in relative liver weight in group B animals as compared to the control animals, which decreased significantly in group C. Haematoxylin and eosin stained sections revealed ballooned hepatocytes having vesicular appearance with pyknotic nuclei in high-fat group which were preserved to a great extent in group C animals. CONCLUSION: This study has shown that use of fresh garlic along with high-fat diet prevents its damaging effects on liver to a great extent.

Fresh garlic amelioration of high-fat-diet induced fatty liver in albino rats.

OBJECTIVE: To observe the effect of fresh garlic on high-fat-diet-induced fatty liver changes. METHODS: The experimental study was conducted at the Jinnah Postgraduate Medical Centre, Karachi, from October to November 2008, and comprised adult albino rats weighing 200-240g each. The rats were divided into 5 groups according to dietary regimen for eight weeks each. Group A received control diet; Group B received high saturated fat diet; Group C received high unsaturated fat diet; Group D received high saturated fat diet with fresh garlic; and Group E received high unsaturated fat diet with garlic for 8 weeks. Liver tissue slides were stained with Oil red-O and haematoxylin and Periodic acid-Schiff-haematoxylin. RESULTS: The 50 rats in the study were divided into five groups of 10(20%) each. There was marked deposition of fat in hepatocyte along with marked decrease in glycogen content in liver of rats in Groups B and C, with Group B showing more marked changes. The changes in fat and glycogen content were reversed and ameliorated close to Group A in rats belonging to Groups D and E. CONCLUSIONS: Fresh garlic minimised the high-fat-diet-induced fatty liver changes in rats.

Prevalence of quinolone-resistant urinary tract infections in Comanche County Memorial Hospital.

PURPOSE: Urinary tract infection (UTI) is not only a common outpatient but also the most frequently occurring nosocomial infection. The most common causative organisms of UTI remain Escherichia coli, nosocomial gram-negative bacilli, enteroccoci and candida. Many physicians use quinolones as the agent of choice for treatment of UTI. As calculated by the drug utilization data of 2007, the rate of quinolone use by physicians for UTI is 48%. This study was performed to determine the prevalence of quinolone-resistant UTI in our hospital and community. METHODS: All patients admitted to Comanche County Memorial Hospital (CCMH) from Jan 2004 to July 2007 with documented positive urine cultures, as well as patients with hospital-acquired UTI's were included in this study. Pertinent data was collected by a retrospective review of medical records. Resistance of E. coli in urine to ciprofloxacin in total number of patients, divided in two age groups, was studied. X2 and P-value were calculated. Data was stratified for age and stratum specific resistance rate of different drugs (% and 95% CI) were calculated. RESULTS: 2000 cases of positive urine cultures were reviewed. The most common organism causing UTI was E. coli in 1225 (61%). Susceptibility reports showed that only 900 of 1225 E. coli (73.5%) were sensitive to quinolones and crude resistance rate to E. coli in older age group was as high as 26.5%. X2 = 200.922 and p-value < 0.001. Resistance was lowest in younger group (18-50), 3.2%, 95% CI of 1.6-4.7 and approached 41% in patients aged 51-90, (95% CI of 37-45). The sensitivity of E. coli to third generation cephalosporins was 100% and to 1st and 2nd generation was 90% and 98% respectively. Klebsiella was sensitive to both quinolones and third generation cephalosporins in 98% and 100% respectively. Other gram negative organisms (Proteus, Pseudomonas) were sensitive to quinolones in only 69% and 57% of cases respectively while being sensitive to cephalosporins (cefepime and ceftazidime in case of pseudomonas) in more than 99% cases. CONCLUSION: Prevalence of quinolone-resistance to most common organisms causing urinary tract infections is significantly high in this community. (26.5% for E. coli). Therefore, in Comanche County Memorial Hospital and community, cephalosporins, preferably third generation, intravenous and oral preparations, rather than quinolones should be the first line of treatment, specially for elderly patients who are started on empirical therapy for UTI.

Perforated appendicitis: accuracy of ct diagnosis and correlation of ct findings with the length of hospital stay.

OBJECTIVE: To determine the sensitivity and specificity of CT findings in the differentiation of perforated from nonperforated appendicitis and correlate CT diagnosis with the length of hospital stay. STUDY DESIGN: An analytical study. PLACE AND DURATION OF STUDY: This study was conducted at Radiology Department of Aga Khan University Hospital, Karachi, from January 2004 to June 2005. PATIENTS AND METHODS: The study included 70 patients who presented with right lower quadrant abdominal pain and underwent pre-operative CT scan followed by appendectomy. Patients were divided into two groups of having perforated and nonperforated appendicitis on the basis of CT scan findings. The surgical and pathological reports combined were considered the reference standard for the diagnosis of perforated appendicitis. Various CT scan findings and average duration of hospital stay in days was compared by t-test. RESULTS: Twenty-six (37%) of 70 patients had perforated appendicitis. It was correctly identified on pre-operative CT scan in 18 patients. There were 18 true positive diagnoses, 43 true negative diagnoses, 1 false positive diagnosis and 8 false negative diagnoses which yielded a sensitivity of 69%, specificity of 97%, positive predictive value of 94% and negative predictive value of 84%. Mean length of hospital stay in perforated group was 6.3 days and 2.9 days in nonperforated group. Severe periappendiceal inflammation, periappendiceal and or abdominopelvic fluid and abscess were significantly associated with perforated appendicitis and with a significant longer hospital stay (p < .001). CONCLUSION: CT scan is 69% sensitive and 97% specific for the diagnosis of perforated appendicitis and constellation of CT findings can be used to select patients with perforated appendicitis for initial non-operative management. Presence of CT signs of significant appendiceal inflammation is independent predictor of longer hospital stay.

Role of magnetic resonance imaging in lumbar spondylosis.

OBJECTIVE: To assess the frequency of various MRI findings in patients with lumbar spondylosis and determine their association with symptoms of patients. DESIGN: Cross-sectional analytical study. PLACE AND DURATION OF STUDY: Radiology Department,The Aga Khan University Hospital, Karachi, from January to December, 2002. PATIENTS AND METHODS: The study included 120 patients who presented with low back and leg pain. Segmental classification system was used to classify the pain distribution. All patients underwent lumbar MRI using 1.5 T-scanner. MRI scans was evaluated for magnitude and location of nerve compression, disc extrusion and the nature of nerve and thecal sac deformation in the central canal, lateral recess and intervertebral foramen at each spinal level. Statistical analysis was performed using computer program SPSS (Version; 10). Chi-square test was also used to determine significance of association between degree of compression, duration of symptoms, site of pain and presence of weakness and numbness. Independent samples test (Levenes test) and Chi-square test were used to determine the significance of associations between age, gender, chronicity of symptoms and MRI findings. A p-value of <0.05 was considered to indicate statistically significant association. RESULTS: The study included 120 patients, the age range was 22 to 88 years (mean 47 years). Twenty-three patients had acute pain of less than 2 months, 40 patients had recurrence of previous symptoms within past 2 months and 57 patients had chronic pain. Disc herniation was most frequent finding seen in 107 patients (89%). Eighty-eight patients (73%) had MRI evidence showing some degree of nerve or thecal sac compression. Severe nerve compression was present in 48 patients (40%). Disc extrusion was present in 22 patients (18%). There was no significant association between segmental distribution of symptoms and presence of anatomic impairment. However, severe nerve compression and disc extrusion were significantly associated with pain distal to the knees. CONCLUSION: The presence of disc extrusion or ipsilateral severe nerve compression at one or multiple side is strongly associated with distal leg pain. There should be a correlation between patient symptoms and signs of sciatica and imaging demonstration of nerve root compression before invasive therapy is undertaken.

Sebaceous carcinoma of the oral mucosa: case report and review of the literature.

Fordyce granules are found in the oral mucosa of up to 80% of adults. However, primary malignant sebaceous tumors of the oral mucosa are exceedingly rare. To our knowledge, only 5 examples of intraoral sebaceous carcinoma have been reported in the literature. This report describes a primary sebaceous carcinoma of the labial mucosa that arose in an area containing numerous Fordyce granules. A brief review of the clinical and histopathologic features of sebaceous carcinoma is also presented.