Persistent Antibody Responses to SARS-CoV-2 Infection in Cancer Patients: A Single-Center Retrospective Observational Study

Introduction There is limited literature available regarding the prevalence and durability of immune response to infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)/coronavirus disease 2019 (COVID-19) in cancer patients.

Objective The aim of this study was to analyze the seroconversion rate in cancer patients recovered from SARS-CoV-2 infection.

Materials and Methods We retrospectively analyzed antibody levels and seroconversion rates in serum samples from 135 cancer patients who had recovered from SARS-CoV-2 infection. Chemiluminescent immunoassay using Roche Cobas e801 analyzer (Roche Diagnostics, Rotkreuz, Switzerland) was performed to identify Pan Ig antibody against nucleocapsid antigen. Reports of first, third, and sixth month were analyzed. Seroconversion was also compared with health-care workers (HCW) of our institute who had recovered from COVID-19 infection.

Results Seroconversion rate in cancer patients was 81.2% at 1 month, 95% at 3 months, and 94.6% at 6 months post reverse transcriptase–polymerase chain reaction positivity. There was no difference in seroconversion rate among different age groups, gender, comorbidities, severity of COVID-19 symptoms, cancer disease status, and treatment with chemotherapy. Seroconversion rate in cancer patients is comparable to HCW (90.4 vs. 96%, p = 0.82) and is durable.

Conclusion Humoral response to COVID-19 infection in cancer patients is comparable to general population and sustained. Such responses suggest that cancer patients are likely to benefit from COVID-19 vaccination.

Differential and synergistic effects of xylanase and laccase mediator system (LMS) in bleaching of soda and waste pulps

AIMS

Investigation of waste pulps and soda pulp bleaching with xylanase (X) and laccase mediator system (LMS) alone and in conjunction (one after the other) (XLMS).

METHODS AND RESULTS

Soda and different grades of waste pulp fibres [used for making three-layered duplex sheets - top layer (TL), protective layer (PL) and bottom layer (BL)] when pretreated with either xylanase (40.0 IU g(-1)) or LMS (up to 200.0 U g(-1)) alone and in combination (one after the other) (XLMS) exhibited an increase in release of reducing sugars [up to 881.0% soda pulp; up to 736.6% (TL), up to 215.7% (PL) and up to 198.0% (BL) waste pulp], reduction in kappa number [up to 17.6% soda pulp; up to 14.0% (TL), up to 25.3% (PL) and up to 10.9% (BL), waste pulp], improvement in brightness [up to 20.4% soda pulp; up to 23.6% (TL), up to 8.6% (PL) and up to 5.0% (BL), waste pulp] when compared with the respective controls. The usage of XLMS along with 15% reduced level of hypochlorite at CEHHXLMS/EHHXLMS bleaching stage reduced kappa number [5.5% soda pulp; 11.4% (TL), 7.9% (PL), waste pulp] and improved brightness [1.0% soda pulp; 0.9% (TL), 1.4% (PL) waste pulp] when compared with the controls. Scanning electron microscopic studies revealed development of cracks, flakes, pores and peeling off the fibres in the enzyme-treated pulp samples. These modifications of the fibre surface during enzymatic bleaching in turn indicated the removal of lignin and derived compounds from the fibre cell wall.

CONCLUSIONS

The work describes synergistic action of xylanase with LMS for bleaching of waste and nonwood pulps for eco-friendly production of paper and thus reveals a new unexploited arena for enzyme-based pulp bleaching.

SIGNIFICANCE AND IMPACT OF THE STUDY

The drastic improvement in pulp properties obtained after xylanase and LMS treatment would improve the competitiveness of enzyme-based, environmentally benign processes over chemicals both economically and environmentally.

Improving the yield and quality of DNA isolated from white-rot fungi

A new simple method used to eliminate polysaccharides that cause problems during DNA isolation was established for 6 different white-rot fungi using 1% hexadecyltrimethylammonium bromide (CTAB) as wash buffer and followed by centrifugation. Variation in the DNA yield and quality was ascertained using precipitating agents, detergents and cell-wall-hydrolyzing chitinase. Considerable amount of exopolysaccharides from fungal biomass was removed with the use of 1% CTAB wash buffer followed by centrifugation. The DNA varied in terms of yield and quality. For the DNA extraction use of 2% SDS in extraction buffer worked best for Pycnoporus cinnabarinus, Cyathus bulleri, Cyathus striatus and Cyathus stercoreus, while 2% CTAB worked best for Phanerochaete chrysosporium and Pleurotus ostreatus. Elimination of phenol and use of absolute ethanol for precipitating DNA resulted in good yield and quality of DNA. This DNA was amenable to restriction endonuclease digestion.

Diabetic muscle infarction: atypical MR appearance

We describe a case of diabetic muscle infarction which had atypical features of hyperintensity of the affected muscle on T1-weighted images. Biopsy was performed which revealed diffuse extensive hemorrhage within the infarcted muscle. We believe increased signal intensity on T1-weighted images should suggest hemorrhage within the infarcted muscle.

Oxidant stress mechanisms in heart failure

Evidences clearly indicate that HF is accompanied by excessive generation of OFRs and depletion of endogenous antioxidant system. The resultant oxidant stress depresses myocardial contractility and function by decreasing Ca++ uptake in sarcoplasmic reticulum and by impaired Ca(++)-ATPase in cardiac tissue. The various sources of OFRs production in HF include increased production of nitric oxide, cytokines, prostaglandins, auto-oxidation of catecholamines, activation of polymorph leucocytes and ischemia induced xanthine-xanthine oxidase. The prevention of oxidative stress by antioxidant translates into better metabolism and function of myocytes. It appears that antioxidant drugs may represent a novel adjunct to the existing therapeutic armamentarium in patients of HF irrespective of its etiology and severity.

Demasking of subclinical left ventricular dysfunction in anemic children

OBJECTIVE

To study subclinical left ventricular dysfunction in anemic children.

SETTING

Hospital.

SUBJECTS

The study population consisted of 52 cases of anemia (16 mild, 14 moderate, 22 severe) and 20 normal age and height matched children aged between 7-12 years.

METHODS

These children were subjected to Echocardiography on Ascuson XP model using 3.5 MHz Transducer during rest and immediately after maximum tolerated exercise on Quniton Model Q-5000 treadmill using modified Naughton protocol. Left ventricular end diastolic dimensions, left ventricular systolic dimension, fractional shortening, left ventricular end diastolic volume, systolic volume, stroke volume and ejection fraction were studied on M-mode echocardiography, and E/A ratio on doppler mode.

RESULTS

Significant differences were observed in resting heart rate, gain in heart rate at peak exercise compared to basal values and double product, total exercise duration and metabolic equivalents at peak exercise in controls and anemic subjects. Left ventricular dysfunction was present in all severely anemic subjects after maximum tolerated exercise on treadmill. The only evidence of left ventricular diastolic dysfunction was in form of decreased left ventricular end diastolic volume after exercise in moderate and severely anemic subjects.

CONCLUSIONS

Exercise is helpful in demasking subtle left ventricular dysfunctions in anemic subjects that are not detected during rest.

Diagnosis of tuberculous meningitis by detection of antigen and antibodies in CSF and sera

OBJECTIVE

To evaluate diagnostic potential of three immunological tests, namely, detection of H37Rv antigen of M. Tuberculosis in CSF, detection of antibodies (IgG) against H37Rv in CSF and detection of antibodies (IgG) against H37Rv in serum for diagnosis of tuberculous meningitis in children.

SUBJECTS

50 children diagnosed as patients of tuberculous meningitis were included as cases and 48 children with CNS diseases of nontubercular etiology [pyogenic meningitis (n = 31), encephalitis (n = 10), seizure disorder of unknown etiology (n = 5), brain tumor (n = 2)] served as controls.

METHODS

H37Rv antigen of M. tuberculosis was detected in CSF by Dot ELISA, and antibodies (IgG) against H37Rv in CSF and serum were detected by Plate ELISA.

RESULTS

Detection of H37Rv antigen in CSF was the most sensitive (90%) and specific (95.83%) with positive and negative predictive values of 95.74% and 90.19%, respectively, followed by detection of antibodies in CSF (sensitivity-74%, specificity-89.58%, positive predictive value-88.10%, negative predictive value-76.78%). Detection of antibodies in serum had low sensitivity (50%), specificity (91.67%), positive predictive value (86.21%) and negative predictive value (63.76%).

CONCLUSIONS

Detection of antigen in CSF is a rapid, sensitive and specific test for diagnosis of tuberculous meningitis in children. Detection of antibody in CSF may be useful in some cases but needs further evaluation. Detection of antibody in serum does not appear to be useful for diagnosis of tuberculous meningitis.

Brainstem auditory evoked response in newborns with hyperbilirubinemia

OBJECTIVE

To determine the initial Brainstem Auditory Evoked Response (BAER) abnormalities in neonates with hyperbilirubinemia and the possible reversibility of abnormal BAER after therapy.

DESIGN

Prospective cohort study.

SETTING

Tertiary care hospital.

SUBJECTS

30 term neonates with hyperbilirubinemia (S. bilirubin < 15 mg/dl) as cases and 25 normal term neonates as controls.

METHODS

Duration of study was from August 1995 to August 1996. BAER were recorded before therapy at peak hyperbilirubinemia, after therapy, and the age of 2-4 months using electric response audiometer (Nihon Neuropack Four Machine). Denver Development Screening Test (Denver II) was performed at 1 year of age.

RESULTS

Seventeen out of thirty (56.7%) neonates with hyperbilirubinemia showed abnormalities on initial BAER. Commonest abnormality seen was raised threshold of wave V in 12 neonates (40%). Other abnormalities observed were absence of all waves at 90 dB (23.3%), prolongation of latencies of various waves (26.7%) and prolongation of various intervals (26.7%). Abnormalities in BAER correlated significantly with bilirubin level. After therapy abnormalities reverted back to normal in 10 cases but persisted in 7 out of 17 (41.17%) cases with initial abnormal BAER. Development screening at 1 yr was abnormal in 3 infants all of whom had persistent abnormalities in BAER.

CONCLUSION

Serial BAER is a useful, non invasive tool to detect neurodevelopment delay secondary to neonatal hyperbilirubinemia.

Cardiovascular responses to treadmill exercise testing in anemia

OBJECTIVE

To study exercise performance on a treadmill in anemic children.

DESIGN

Prospective case control study.

SETTING

Department of Pediatrics and Intensive Care Unit, Department of Medicine, King George's Medical College, Lucknow.

SUBJECTS

The study population consisted of 41 cases of anemia (10 mild, 21 moderate and 10 severe) and 11 normal age and height matched children aged between 7-12 years.

METHODS

These subjects were exercise tested on Quinton Model Q5000 treadmill using Modified Naughton Q5000 protocol. Heart rate, systolic blood pressure, double product, ECG changes, exercise duration and metabolic equivalents achieved during peak exercise were studied. Statistical analysis was performed using analysis of variance (ANOVA) test.

RESULTS

No significant difference was observed in values of resting heart rate, heart rate at peak exercise, recovery heart rate, blood pressure response, resting double product, double product at peak exercise, recovery double product and ECG changes in any of the study groups (p > 0.05). However, the gain in heart rate at peak exercise compared to basal value, and double product, total exercise duration and metabolic equivalent (MET) values at peak exercise were significantly low in anemic children on comparison to normal controls (p < 0.001).

CONCLUSIONS

Cardiovascular responses are blunted in anemia, mainly because of depleted cardiac reserve.

Brainstem auditory evoked response in tuberculous meningitis

Brainstem auditory evoked response (BAER) abnormalities in tuberculous meningitis (TBM) were determined in 50 cases of tuberculous meningitis (36 male and 14 female) and 50 normal healthy children. Fifty six per cent cases had abnormal BAER findings. The commonest BAER abnormality observed in 32% was a combination of prolonged latency and prolonged interval while unilateral and bilateral absent response was observed in 4% cases. Prolonged latency was observed in 16% patients. Seizure activities, modified glasgow coma scale (GCS), raised intracranial pressure (ICP) and TBM stage III were significantly correlated with abnormal BAER, while age, sex, duration of illness, depressed sensorium, neurological deficit and CSF findings did not have a significant correlation with abnormal BAER. Follow up could be done in ten patients only. All the three patients with only prolonged latency had a normal BAER on follow up, two out of four patients with prolonged latency and prolonged interval had normalization of BAER while in three patients, initial as well as follow up BAER was normal. The present study shows that BAER abnormalities are observed in more than fifty per cent of the patients of tuberculous meningitis.

Brainstem auditory evoked response in neonates with birth asphyxia

OBJECTIVE

To determine the brainstem auditory evoked response (BAER) abnormalities and their reversibility in neonates with birth asphyxia.

DESIGN

Prospective case control study.

SETTING

Tertiary care teaching hospital.

METHODS

30 term Neonates with 5-min Apgar < 6 and hypoxic ischemic encephalopathy (HIE) underwent BAER testing with follow up at 3 months. An equal number of normal term neonates served as controls.

RESULTS

13 out of 30 (43.3%) neonates with birth asphyxia showed some abnormality in BAER wave form. The commonest type of BAER abnormalities seen were transient prolongation of latencies of various waves (69.2%) and prolonged interside latency difference (69.2%). Other abnormalities observed were prolonged interwave interval (23.1%) and prolonged interside interval difference (7.7%). Abnormalities in BAER were significantly associated with stages of HIE and duration of neurological abnormalities more than 5 days. On follow up of 16 cases at 3 months of age, BAER abnormalities reverted back to normal in all the neonates. The Denver Developmental Screening Test (DENVER II) was suspect in 4 cases but the BAER was normal.

CONCLUSION

BAER abnormalities in asphyxic neonates are transient and revert back to normal at 3 months of age. BAER does not appear to be a useful tool for early detection of neurological handicaps.

Brainstem auditory evoked response (BAER) in childhood bacterial meningitis

Brainstem auditory responses were recorded in 50 children of bacterial meningitis and age matched 50 normal children. Abnormal BAER was found in 32 (64%) patients of bacterial meningitis. These abnormalities included prolonged latency (56.2%); unilateral absent response (25%); bilateral absent response (25%) and prolonged interwave interval (25%). Follow-up could be done in 23 patients of 46 survivors. All the patients with prolonged latency either became normal or improved. In majority of the patients having absent response, the abnormality persisted. Abnormal BAER was significantly associated with age < 2 years (p < 0.02), Modified GCS Score < or = 8 (p < 0.001), Seizures (p < 0.02), raised Intracranial Pressure (ICP) (p < 0.02) and CSF sugar < 20 mg% (p < 0.05).

Perinatal mortality in urban slums in Lucknow

OBJECTIVES

To determine the perinatal mortality rate (PNMR) in the urban slums of Lucknow

DESIGN

Cross-sectional survey.

SETTING

Twenty five Anganwadi centres of urban Lucknow, with a population of 25,901.

METHODS

Data was collected on birth and early neonatal deaths, gestational age of the neonate (determined at birth) and maternal variables like socio-economic status, maternal age, parity, and bad obstetrical history from January 1992 to March 1993.

RESULTS

There were 966 births with a still-birth rate of 37.2 and PNMR of 59.0 per 1000. The relative risk of perinatal mortality with lower socio-economic status was 1.87, bad obstetrical history 2.18, and gestational age < 37 weeks 1.95.

CONCLUSIONS

Further reduction in PNMR may be possible with focussed medical services to women of low socio-economic status having bad obstetrical history and those delivering before term.

Pulmonary function tests in normal Indian children and changes in respiratory disorders

To document the normal values of pulmonary function tests in children and changes occurring in their values with various respiratory disorders, a study was carried over a period of one year in 95 healthy controls (39 females and 56 males) of 8-13 years of age and 51 cases with respiratory disorders (bronchial asthma-31, pneumonia-10, empyema-10) of matched age, sex and height distribution. The lung functions studied were FVC, FEV1, FEV1/FVC, PEFR and FEF25-75%. In children with bronchial asthma, the FEV1/FVC%, PEFR and FEF25-75% were reduced in accordance with the severity of the disease. A typical restrictive pattern of equivalent decrease in FVC and FEV1 along with insignificant lowering of flow rates, i.e., PEFR and FEF25-75% was observed in pneumonia whereas in patients of empyema a combined pattern of significantly decreased FVC and FEV1 along with mildly reduced FEV1/FVC%, PEFR and FEF 25 75% was observed.

Outcome in relation to Apgar score in term neonates

Sixty four asphyxiated term babies (Apgar score of 6 or less at 5 minutes) and 90 non-asphyxiated term babies (controls) were studied. Of these, 40 cases and 48 controls could be followed up. Mortality and neurodevelopmental outcome were studied in both the cases and controls. Mortality and poor neurodevelopmental outcome correlated inversely with the Apgar scores at 5 and 10 minutes. The outcome of babies with low 5 minute Apgar scores was significantly better than those with the same scores at 10 minutes. Symptomatic neonates when compared to asymptomatic neonates with same Apgar score showed significantly poorer outcome. Babies with Apgar scores of 6 at 5 or 10 minutes behaved like the controls both in terms of mortality and neurodevelopmental outcome.

Computed tomography of brain in symptomatic birth asphyxia

Twenty five asphyxiated newborns (seventeen term and eight preterm) with mean gestational age of 37 weeks (range 28-48 weeks) and mean birth weight of 2.4 kg (range 0.75 kg to 3.5 kg), respectively, constituted the cases in present study. Normal CT scan was found in five term (29.4%) and two preterm babies (25%). CT abnormalities noted in term babies included hemorrhage (subarachnoid 5.8%, intracerebral 11.6%), hypodensity (mild 23.2%, moderate 11.6% severe 5.8%); hypodensity with hemorrhage 5.8% and cerebral atrophy 5.8%. In the preterm babies abnormalities included intraventricular hemorrhage in 25%, isolated hypodensity in 37.5% and hypodensity with hemorrhage in 12.5% cases. Where as mild hypodensity on CT scan in the absence of hemorrhage or other gross abnormality was indicative of a favourable outcome, moderate to severe hypodensity was indicative of ischemic brain injury and an unfavourable outcome. The presence of intraventricular hemorrhage irrespective of the size of bleed was associated with mortality in all in the present study.

Renal failure in symptomatic perinatal asphyxia

The study included seven term newborns developing acute renal failure due to symptomatic perinatal asphyxia in early neonatal period. Its diagnosis was based on clinical and biochemical indices. Urinary output, serum and urinary sodium, potassium and creatinine, and blood urea nitrogen were evaluated in all of them. All the patients had oliguria not responding to fluid challenge and/or diuretic therapy, high serum K, FeNa of greater than 2.5% and RFI of greater than 3 indicative of intrinsic renal disease. The condition was associated with a very high mortality.

Effects of preformed immune complexes on liver enzymes & their serum clearance in mice

Two different performed HSA-anti-HSA immune aggregates, insoluble complex at equivalence (IC-E) and soluble complex with 5 times antigen excess (IC-S)-were administered iv in experimental mice to study their interaction with liver cells. Both complexes produced no appreciable change in the levels of liver enzymes like acid phosphatase, cathepsin D and gamma-glutamyl transferase. However, marked reduction in the level of liver pseduocholinesterase (as much as 93%) was recorded in the treated animals under identical conditions of administration of both the complexes. Hepatic uptake studies revealed that within 5 min, maximal sequestration of IC occurred within the liver (10 to 18%) and the blood (70 to 82%) when computed in terms of total injected radioactive IC. After 4 h, radioactivity dropped to 3 per cent in liver and 50-40 per cent in blood. The liver seemed to be incapable of scavenging all the serum complexes at a time. Significant consumption of serum complement occurred, when freshly prepared complexes were administered to the animals, but the reduced complement level showed a tendency to reach normalcy after 2 h. The soluble and equivalence zone IC failed to exhibit identifiable discrimination facets with respect to handling by liver. The complexes IC-E and IC-S also behaved in a similar manner.

Reduction in pulmonary and hepatic respiratory cytochrome contents by fly ash inhalation in rats

Exposure of rats to fly ash for 15 days, 6 hours daily, inhibited pulmonary and hepatic NADH-oxidase activity. The content of cytochrome b and cytochromes a + a3 was significantly lower in the lungs of the fly-ash-exposed group. However, in liver, fly ash exposure reduced the cytochrome a + a3 level without affecting the cytochrome b content, indicating a tissue-specific effect. Mitochondrial protein content in both organs was the same in both groups.