Citrobacter freundii-associated osteomyelitis and thromboembolic events following Moderna COVID-19 vaccination: a rare case report from Nepal

Introduction

Vaccination against coronavirus disease 2019 (COVID-19) is essential for controlling the ongoing cases of this disease. Citrobacter infections of the bones and joints are extremely uncommon. Thromboembolism and deep vein thrombosis (DVT) are very rare complications.

Case presentation

The authors present a rare case of osteomyelitis, septic arthritis, deep venous thrombosis, and pulmonary embolism in a 15-year-old previously healthy boy occurring shortly after receiving the second dose of the Moderna COVID-19 vaccine. He experienced pain, swelling in the right leg, shortness of breath, and fever, followed by chest pain and leg edema. Treatment included anticoagulation, ketorolac for pain management, antipyretics, and intravenous antibiotics (Tazobactam/Piperacillin, Linezolid, Clindamycin) for osteomyelitis.

Discussion

The risk of COVID-19 vaccine-related thrombotic events is minimal. Thrombotic events reported among mRNA is very rare. Citrobacter freundii bone and joint infections are very rare, accounting for a small percentage of cases. Some documented cases include cefotaxime-resistant strains causing necrotizing fascitis and osteomyelitis, including postarthroplasty infections. Due to the diverse range of susceptibility patterns and the widespread occurrence of drug resistance, personalized treatment based on culture and sensitivity testing is recommended. However, in rare cases, severe complications like DVT and joint infections associated with Citrobacter infection may occur and should be reported to the vaccine adverse events reporting system.

Conclusion

Administering the COVID-19 vaccine to enhance natural antibodies is crucial, despite the low risk of infection, thromboembolism, and DVT. Healthcare providers should stay vigilant about adverse effects postvaccination and promptly report those cases.

Intestinal tuberculosis can masquerade as Crohn's disease: A teachable moment

Intestinal tuberculosis and Crohn's disease are chronic granulomatous diseases with similar clinical presentations and can mimic one another. Their treatment modalities are completely different; however, sometimes it is challenging to differentiate them. We report a case of a 51-year-old female presenting with abdominal pain and on-and-off diarrhea for 4 years with weight loss. Clinical symptoms along with multiple aphthous ulcers in the terminal ileum and negative tuberculin test favored the diagnosis of Crohn's disease. The patient did not respond to steroids. A repeat colonoscopy with acid-fast bacilli stain showed Mycobacterium tuberculosis. This case highlights that acid-fast bacilli culture and tuberculosis polymerase chain reaction to confirm or rule out the diagnosis of intestinal tuberculosis in all patients suspected of Crohn's disease.

Phonon anharmonicity in binary chalcogenides for efficient energy harvesting

Thermoelectric (TE) materials have received much attention due to their ability to harvest waste heat energy. TE materials must exhibit a low thermal conductivity (κ) and a high power factor (PF) for efficient conversion. Both factors define the figure of merit (ZT) of the TE material, which can be increased by suppressing κ without degrading the PF. Recently, binary chalcogenides such as SnSe, GeTe, and PbTe have emerged as attractive candidates for thermoelectric energy generation at moderately high temperatures. These materials possess simple crystal structures with low κ in their pristine forms, which can be further lowered through doping and other approaches. Here, we review the recent advances in the temperature-dependent behavior of phonons and their influence on the thermal transport properties of chalcogenide-based TE materials. Because phonon anharmonicity is one of the fundamental contributing factors for low thermal conductivity in SnSe, Sb-doped GeTe, and related chalcogenides, we discuss complementary experimental approaches such as temperature-dependent Raman spectroscopy, inelastic neutron scattering, and calorimetry to measure anharmonicity. We further show how data gathered using multiple techniques helps us understand and engineer better TE materials. Finally, we discuss the rise of machine learning-aided efforts to discover, design, and synthesize TE materials of the future.

Dementia Symptoms among Senior Citizens Living in Geriatric Homes of Kathmandu Valley

Background With increasing age, the older population becomes more susceptible to mental disorders. It is important to recognize and develop an understanding of psychiatric morbidity particularly among the residents of geriatric homes in resource-poor settings. Objective To assess the prevalence and associated factors of dementia symptoms among Nepalese senior citizens living in geriatric homes of Kathmandu valley. Method A cross-sectional study was conducted among 304 senior citizens living in geriatric homes of Kathmandu valley. Cognitive Impairment Test (CIT), was used to assess dementia symptoms. Bivariate and multivariate logistic regressions were performed. All the variables that were significant at p < 0.05 level in the bivariate analysis were included in the multivariate regression model and statistical significance was declared at p < 0.05 with a 95.00% confidence interval (CI). Result This study showed 75.65%, of the participants, had dementia symptoms. In the multivariate logistic regression analysis, female respondents (AOR=2.94, 95% CI=1.31-6.57), respondents never received geriatric allowances (AOR=2.46, 95% CI=1.22-4.98), respondent's history of alcohol consumption habits (AOR=2.04, 95% CI=1.01-4.11) and non-vegetarian diet habits (AOR= 2.31, 95% CI=1.12-4.76) were found more likely to had higher dementia symptoms whereas, literate participants (AOR=0.19, 95% CI=0.08-0.43) were less likely to had dementia symptoms. Conclusion The high prevalence of dementia symptoms among senior citizens living in geriatric homes in the Kathmandu valley indicates an urgent need for early diagnosis and treatment of mental disorders among senior citizens to improve their quality of life and well-being.

Knowledge Regarding Earthquake Preparedness Among the People of Biratnagar Sub-Metropolis of Eastern Nepal

IntroductionEarthquake preparedness is necessary strategy and action that is done before an earthquake happens in order to decrease mortality and morbidity. Earthquake in Nepal killed more than 8000 people in 2015. Increased number of deaths were mainly considered due to lack of earthquake preparedness and necessary safety measures.ObjectivesThe aim of this study was to assess the knowledge regarding earthquake preparedness and to find out relationship between the level of knowledge and with their selected socio-demographic variables.MethodologyA cross sectional study was conducted among the people residing in ward number 11 and 18 of Biratnagar sub-metropolis from 1st July to 1st October 2015. Wards were selected through simple random sampling and 110 participants were selected through convenient sampling. Each participant had completed an interviewer-administered questionnaire. Descriptive and inferential statistics was applied for data analysis.ResultAmong 110 participants, 51.8% had knowledge score between 51% to 75%, 24.6% had knowledge score below 50% and only 23.6% had knowledge score above 75%. This research showed that there was significant relationship between knowledge and age, marital status, educational status, occupation and monthly income. Participants from 20 to 39 year had more knowledge score than participants from 40 to 60 years. The higher the educational status; more was the knowledge score. Unmarried participants had more knowledge score than married participants and business holders had more knowledge score than other occupation category.ConclusionEarthquake preparedness knowledge among participants was inadequate. Therefore, educational intervention program regarding this is required in these areas. Birat Journal of Health Sciences Vol.2/No.1/Issue 2/ Jan - April 2017, page: 201-205

Diabetes Awareness Among Patient's Attendant Visiting in Teaching Hospital of Eastern Nepal

IntroductionDiabetes is a prevalent non-communicable disease. It has  increasing global trend. In Nepal, the prevalence of diabetes is also increasing. Awareness is vital to  revent and early diagnosis of diabetes.ObjectivesThe objective of study was to assess the awareness of diabetes and its related factors.MethodologyThis was a hospital based cross sectional study. Total of 503 patient's a

Treatment Outcome of Drug Resistance Tuberculosis From a Centre of Eastern Region, Nepal

Introduction Drug resistance tuberculosis (DRTB) has become major problem worldwide with difficulty in treatment. Objective The study is conducted to find the incidence and outcomes of DRTB in one of the eastern tuberculosis treatment centre of Nepal.Methodology We collected all the cases of DRTB being treated from national anti-tuberculosis association of Biratnagar, Nepal. There were altogether 154 patients, who had sputum culture with resistance of at least one anti tubercular drug (ATD), included in this study.Results Of 154 total patients, 36 patients were resistant to rifampicin only, 84 patients were resistant to isoniazid and rifampicin, 18 patients were resistant to isoniazid, rifampicin and ethambutol and 16 patients were resistant to isoniazid, rifampicin and either streptomycin or fluoroquinolone. There was overall 71% cure rate in case of drug resistance tuberculosis. There was only statistical difference between cured and died patients in case of sputum conversion time with earlier sputum conversion in cured patients. Similarly, patients who were previously treated with category 2 ATD had only resistance to ethambutol or streptomycin or fluoroquinolone besides resistance to isoniazid and rifampicin compared to new patients and patients treated with category 1 regimen; as these groups were not found to be resistant to first three drugs.Conclusion There was overall 71% cure rate in case of drug resistance tuberculosis. Earlier sputum conversion was seen in cured patients compared to those who died during the treatment. Multiple drugs were resistant in patients previously treated with category 2 Anti-tubercular drugs.Birat Journal of Health Sciences 2016 1(1): 20-26

Effectiveness of Educational Intervention Programme on Knowledge Regarding Breast Self Examination Among Higher Secondary School Girls of Biratnagar

Introduction Breast self-examination (BSE) is a self-generated, non-invasive and non-irradiative method of breast cancer detection. Self examination of the breasts each month after the menstrual cycle is the simplest yet extremely important way to detect early breast cancer. It has been observed that women can detect 95% of breast cancers and 65% of early minimal breast cancers themselves. This method is harmless, less time consuming and can be performed by any woman.Objective To assess the effectiveness of educational intervention programme regarding Breast Self Examination among girl students of study school.Methodology Pre experimental one group pre-test post-test design was adopted for this study. In total, 61 girls were included. The result were analysed by using both descriptive as well as inferential statistics.Results In pre-test 75.4% had inadequate and only 1.6% had adequate knowledge regarding Breast Self Examination, in contrast, after the intervention the adequate knowledge was increased to 62.3%. The overall mean score was increased from 33.07% to 85.14%. The test of significance revealed that the increment in BSE knowledge score due to program intervention was highly significant (P< 0.001).Conclusion The educational intervention programme on BSE was found to be highly effective as the knowledge score was significantly increased after intervention of the package among higher secondary school girls.Birat Journal of Health Sciences 2016 1(1): 13-19

Modulation of Hemopoiesis in Normal and Tumor-Bearing Mice on in Vivo Administration of FK565

The present investigations were undertaken to study the effect of in vivo administration of FK565 on the process of hemopoiesis in normal and tumor-bearing mice. FK565 administration (10 mg/kg body weight) of normal mice resulted in an enhancement of the bone marrow cell (BMC) colony foming activity (CFA) and proliferation in vitro. The counts of granulocyte- and granulocyte macrophage-colony forming units (CFU-G and CFU-GM) were significantly enhanced in the BMC of FK565-treated group. The total leukocyte count (TLC) was also augmented after FK565 administration. The differential leukocyte count (DLC) revealed an enhancement of the neutrophil count in the FK565-treated mice. A similar pattern of BMC proliferation, CFA, TLC and DLC was observed in P815 tumor-bearing mice. FK565 administration of the tumor-bearing mice, however, did not significantly alter the CFA, TLC and DLC.

Anti-proliferative effects of γ-tocotrienol are associated with suppression of c-Myc expression in mammary tumour cells

OBJECTIVES

Aberrant c-Myc activity plays a central role in cancer transformation. γ-tocotrienol is a member of the vitamin E family that displays potent anti-cancer activity. Here, studies were conducted to determine the role of c-Myc in mediating anti-proliferative effects of γ-tocotrienol in mammary cancer cells.

MATERIALS AND METHODS

Treatment effects on mouse +SA and human MCF-7 mammary cancer cell proliferation were determined by MTT assay and Ki-67 staining. Protein expression was determined by western blot analysis. Immunofluorescence staining and qRT-PCR were used to characterize cellular c-Myc and MYC levels respectively.

RESULTS

Anti-proliferative effects of γ-tocotrienol were associated with reduction in total c-Myc and phosphorylated-c-Myc-serine 62, and increase in phosphorylated-c-Myc-threonine 58 levels. γ-tocotrienol also reduced PI3K/Akt/mTOR and Ras/MEK/Erk mitogenic signalling, cyclin D1 and cyclin-dependent kinase 4 levels, and increased p27 levels. However, γ-tocotrienol had no effect on MYC mRNA levels. γ-tocotrienol also increased levels of FBW7 (E3 ligase that initiates ubiquitination of c-Myc), but had no effect on serine/threonine phosphatase PP2A or isomerase Pin 1 levels. Combined treatment with GSK3α/β inhibitor LiCl or proteasome inhibitor MG132 blocked γ-tocotrienol-induced reductions in c-Myc.

CONCLUSIONS

These findings indicate that anti-proliferative effects of γ-tocotrienol are associated with reduction in c-Myc that results from increase in GSK-3α/β-dependent ubiquitination and degradation, rather than from reduction in c-Myc synthesis in +SA and MCF-7 mammary cancer cells.

Abstract P3-03-09: Anti-proliferative dose of g-tocotrienol decreases c-Myc stability in breast cancer cells

c-Myc is a helix-loop-helix leucine zipper transcription factor that has essential role in controlling many cell functions, including cell proliferation, differentiation, growth and apoptosis. However, c-Myc overexpression has been reported to occur in a majority of breast cancers and is associated with a poor prognosis. Apart from MYC gene amplification and translocation, it is also tightly regulated by signaling pathway that involves series of interdependent phosphorylation events. Myc stability is increased by phosphorylation at serine 62 (S62) by extracellular signal-regulated kinase (ERK) or cyclin dependent kinase (CDK), whereas subsequent phosphorylation at threonine T58 (T58) by glycogen synthase kinase b (GSK3 β) triggers dephosphorylation of S62 by protein phosphatase 2A-B56α (PP2A- B56α), leading to unbiquitination by SCF-Fbw7 E3 ligase and proteasomal degradation. Additionally, it has been shown that primary human breast cancer cells display increased levels of S62 Myc and decreased level of T58 Myc and mutations in this pathway result in accumulation of high level of oncogenic S62 Myc leading to tumorigenesis. γ-tocotrienol (γT3), a member of the vitamin E family has potent antiproliferative and apoptotic activity in a variety of cancer cell types at treatment doses that have little or no effect on normal cell viability or growth. Additionally, previous studies have shown that anti-proliferative dose of γT3 decreased c-Myc protein level in colorectal and pancreatic cancer cells. Therefore, studies were conducted to determine if γT3 decreases oncogenic S62 phosphorylation and triggers subsequent interdependent phosphorylation leading to c-Myc degradation in neoplastic mouse +SA and MCF-7 human epithelium mammary cancer cell lines. Treatment with 1-8μM γT3 resulted in a dose-responsive inhibition of +SA and MCF-7 breast cancer cell growth. Western blot analysis showed that antiproliferative dose of γ-tocotrienol resulted in a decrease in total c-Myc, phospho S62 Myc and increase in phospho T58 Myc in +SA and MCF-7 breast cancer cells. Further studies showed that similar doses decreased phosphorylated (activated) Akt and its downstream targets GSK-3β and mTOR, as well as phosphorylated (activated) 44/41 MAPK or (Erk 1/2). Additional studies showed that the antiproliferative effects of γT3 were also associated with a decrease in cyclin D1 and cyclin dependent kinase 4 (CDK4). Western blot analysis has also shown an increase in FBw7, an E3 ligase that initiates ubiquitination of c-Myc. However, no change in protein phosphatase 2A (PP2A) and Pin 1 prolyl isomerase was observed in +SA and MCF-7 mammary cancer cells. In summary, these findings demonstrate that the antiproliferative effects of γ-tocotrienol are mediated, at least in part, by decreasing oncogenic c-Myc (S62) levels and a corresponding reduction in Akt/mTOR and MAPK signaling. These effects were also associated with an increase in GSK-3β-induced phosphorylation of T58 and the promotion of the ubiquitination and degradation of c-Myc. This study was supported by grants from First Tech International Ltd., and the Malaysian Palm Oil Council.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-03-09.

Abstract P3-03-11: Oxazine derivatives of g- and D- tocotrienols display potent anticancer effects in vivo

Breast cancer is a multi-stage process which leads to the accumulation of abnormal cells arising from excessive proliferation, lack of apoptosis or a combination of both. Natural compounds such as g-tocotrienol have been shown to selectively inhibit cancer cell growth without harming normal cell viability with little or no adverse side effects. The antiproliferative and apoptotic effects of the tocotrienol isoform, γ-tocotrienol, have been firmly established in various cancer types. However, in vivo studies have provided mixed results, attributed to γ-tocotrienol rapid clearance and low bioavailability. In order to improve anticancer potency and bioavailability in vivo, γ- and Δ-tocotrienol were chemically modified with electrophilic substitution reactions on their chromane ring using Mannich and Lederer-Manasse reactions, resulting in the synthesis of various oxazine derivatives. Several of these oxazine derivatives (compounds 26, 31, 39, 40 and 44) were found to display potent anticancer activity as compared to their parent compounds when tested on +SA mammary cancer cells grown in culture. These in vitro studies were followed up with in vivo studies to determine the anticancer effects of oxazine derivatives on the growth of mammary tumors in mice. Female syngeneic BALB/c mice, 4-6 week old were inoculated with 1×106 +SA mammary tumor cells in the left mammary pad. Once tumor size reached 5mm in diameter, animals were divided into different treatment groups and received an intra-tumoral injection injected of 0-120μg/20μl tocotrienol or its derivative every other day for 11 days. Afterwards, mice were sacrificed, tumors removed and placed in -80°C until further analysis. Results from these studies showed that tumor growth rate was significantly reduced in the oxazine derivative treated animals as compared to the vehicle-treated controls. Western blot analysis of tumor samples showed that the growth inhibitory effects of tocotrienol derivatives was also associated with a significant reduction in phosphorylated (activated) Akt and reductions in cell cycle regulatory proteins cyclin D1 and cyclin dependent kinases (CDK2, CDK4 and CDK6). In addition, oxazine derivative treatment was also associated with a large increase in CDK inhibitors p21 and p27, as compared to tumors obtained from the vehicle-treated control mice. Western blot analysis also showed that tumor from oxazine-derivative treated mice displayed a large reduction in NFκB levels and its downstream gene product COX-2. In summary, oxazine derivatives of tocotrienols display more potent anticancer activity both in vitro and in vivo, as compared to their parent compounds and suggest that these tocotrienol derivatives may provide some benefit as novel anticancer therapeutic agents. This work was supported, in part, by First Tec International Ltd. (Hong Kong), Malaysian Palm oil Council and the Louisiana Cancer Foundation.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-03-11.

Level of compliance and factors associated with non-compliance to treatment among the mentally ill patients

Background: Mental illnesses are treatable and need medication and other therapies i.e. counseling, psychotherapy etc for the better outcome. Poor adherence to psychiatric medication regimens is a major obstacle to the effective care of persons who have chronic mental illness.Objectives: The study aims to identify the level of compliance and factors associated with non-compliance to treatment regimen.Methods: This was a hospital based cross sectional study carried out in psychiatric ward and OPD at B.P.Koirala Institute of Health Sciences, Dharan Nepal. A total of 150 patients were included as study samples using purposive sampling technique. Data was collected using self developed, pre tested, semi structured Pro forma by interview method.Results: Half of the patients showed average compliance. Thirty seven percentages of patients had good compliance and only 13% showed poor compliance. There was no association between drug compliance and demographic variables (p> 0.05). Drug compliance was significantly associated with factors such as drug related aspects, treatment access related factors, quality of interaction with treating team, family support, attitude towards mental illness and relatives' insight towards mental illness (p<0.05 ).Conclusion: The findings of the study highlighted the various factors such as drug related, social support, and treatment access related factors are influencing the drug compliance among the mentally ill patients.DOI: http://dx.doi.org/10.3126/hren.v10i2.6577 Health Renaissance 2012; Vol 10 (No.2); 113-117 

Substance Use among Medical Students in Kathmandu Valley

Introduction: Substance use including tobacco and alcohol is the most important cause of preventable morbidity, disability, and premature mortality. The study aims to specify the prevalence and the pattern of use of different substance. Methods: A cross sectional study was performed amongst first year and final year students in four medical colleges in Kathmandu using self administered anonymous questionnaire.Data collectedfrom 446 students were analyzed. Results: Prevalence of substance use was found to be 60.3% among the medical students. Alcohol (57.6%) was the substance most prevalently used followed by tobacco (27.58%) and cannabis (12.8%). Mean age of first exposure was 17.94 (Confidence interval: 17.91-17.97). There was significant difference in the useof tobacco and cannabis amongst final year students than first year students. Male and female differed significantly in use of every substance except for benzodiazepine. Medical college, college and school were place of first exposure in 17.26%, 15.92% and 13.23% of the cases respectively. Family history was associated with substance use in medical students and was statistically significant (P<0.0001).Experimentation was the major reason for the use of most of the substances. Conclusions: Substance use is prevalent in male medical students of both first and final year. Hence steps should be initiated early in school, college and medical college to prevent substance use. Keywords: alcohol, medical students, substance use, tobacco.

Substance use among medical students in Kathmandu valley

INTRODUCTION

Substance use including tobacco and alcohol is the most important cause of preventable morbidity, disability, and premature mortality. The study aims to specify the prevalence and the pattern of use of different substance.

METHODS

A cross sectional study was performed amongst first year and final year students in four medical colleges in Kathmandu using self administered anonymous questionnaire.Data collectedfrom 446 students were analyzed.

RESULTS

Prevalence of substance use was found to be 60.3% among the medical students. Alcohol (57.6%) was the substance most prevalently used followed by tobacco (27.58%) and cannabis (12.8%). Mean age of first exposure was 17.94 (Confidence interval: 17.91-17.97). There was significant difference in the useof tobacco and cannabis amongst final year students than first year students. Male and female differed significantly in use of every substance except for benzodiazepine. Medical college, college and school were place of first exposure in 17.26%, 15.92% and 13.23% of the cases respectively. Family history was associated with substance use in medical students and was statistically significant (P<0.0001).Experimentation was the major reason for the use of most of the substances.

CONCLUSIONS

Substance use is prevalent in male medical students of both first and final year. Hence steps should be initiated early in school, college and medical college to prevent substance use.

Antidiabetic plants used by Sikkim and Darjeeling Himalayan tribes, India

Sikkim and Darjeeling Himalayan region is characterized by a rich floral diversity and an equally rich ethnomedicinal tradition. Herbal medicine is the dominant system of medicine practiced by the local tribes of this region for the treatment of diabetes. During the course of the present studies it was found that 37 species of plants belonging to 28 families are used as antidiabetic agents in the folk medicinal practices in the region and 81% of these plants are hitherto unreported as hypoglycemic agents. This finding may lead to serious research towards developing new and efficient drugs for diabetes.

Immunization with wild-type p53 gene sequences coadministered with Flt3 ligand induces an antigen-specific type 1 T-cell response

We examined the ability of immunization with sequential adenovirus/plasmid DNA vectors expressing human wild-type p53 to stimulate a type 1 T-cell response and induce protection against challenge from a metastatic tumor that expresses mutated murine p53. We found that tumor protection and an antigen (Ag)-specific immune response were enhanced by prior injection of Flt3 ligand (Flt3L) at a dose and schedule that significantly increased dendritic cell (DC) number and frequency. Preliminary studies using enzyme-linked immunospot and Winn assays suggested that Ag-specific CD8 cells, with their significant increase in IFN-gamma-secreting activity (Tc1 cells), were responsible for the tumor protection. The delayed-type hypersensitivity response to p53 was increased in mice immunized with p53 alone or p53 and Flt3L compared with a negative control. In contrast, spleen cells from mice immunized with p53 and Flt3L exhibited a higher Ag-specific proliferative response than mice immunized with p53 alone. The frequencies of Ag-specific IFN-gamma and interleukin (IL)-4-secreting cells were determined using an enzyme-linked immunospot assay, which demonstrated that the frequency of IFN-gamma-secreting cells was significantly higher in mice immunized with p53 and Flt3L than in mice receiving Flt3L, excipient, or p53 treatment alone. In contrast, the frequency of IL-4-secreting cells did not differ significantly among these groups. We also observed an increased frequency of IL-12 and IFN-gamma-secreting cells (but not IL-4 or IL-10) in the spleens of mice immediately after 10 days of Flt3L treatment, which was also the day of p53 priming. This observation supports the likelihood that there are multiple mechanisms of Flt3L adjuvant activity, including expansion of DC and type 1 T-cell number. Overall, these results suggest that immunization with p53 genetic sequences after in vivo expansion of DC, using Flt3L, provides a useful strategy to induce p53-specific, and protective, type 1 T-cell responses.

Flt3 ligand and granulocyte-macrophage colony-stimulating factor preferentially expand and stimulate different dendritic and T-cell subsets

OBJECTIVE

Mechanisms of T-cell stimulation by Flt3 ligand (Flt3L) and granulocyte-macrophage colony-stimulating factor (GM-CSF) remain unclear. Herein, we compared the effects of Flt3L and GM-CSF on the expansion of dendritic cells (DC) and T-cell subsets and cytokine expression.

METHODS

Naïve and effector/memory T cells were analyzed by flow cytometry (FC). CD4(+) and CD8(+) T cells and CD11c(+)CD11b(dull/-)(DC1) and CD11c(+)CD11b(+) (DC2) subsets were isolated and the frequency of IFN-gamma-, IL-12- (type 1) and IL-4-, IL-10 (type 2)-producing cells and cytokine mRNA expression evaluated.

RESULTS

Flt3L expanded both DC1 and DC2 subsets with a significantly higher percentage and number of DC1 than DC2, while GM-CSF preferentially expanded the DC2 subset. Isolated DC1 from Flt3L-injected mice had significantly higher levels of IL-12 (p40) than IL-10, while the converse occurred with DC2. The numbers of naïve and memory T cells were elevated in mice that received Flt3L or GM-CSF. However, the number of memory CD4(+) and CD8(+) T cells was significantly increased in Flt3L as compared to GM-CSF cohorts. While GM-CSF increased the frequency of both type 1 and type 2 cytokine-producing cells, Flt3L significantly augmented the frequency of type 1 T cells.

CONCLUSIONS

In contrast to GM-CSF, Flt3L preferentially induces the expansion of type 1 T cells. The mechanism of Flt3L-induced T-cell stimulation is associated with the expansion of the IL-12 (p40)-producing DC1 and memory T cells.

Human interferon-gamma enhances expression of ganglioside GM2 on human lung cancer cells and their susceptibility for antiganglioside GM2 monoclonal antibody-dependent cellular cytotoxicity

Interferons are known to modulate several cellular functions by the induction of various proteins. In this study, we demonstrated that human interferon-gamma (HuIFN-gamma) enhanced the expression of ganglioside GM2 (GM2), which is a kind of tumor-associated antigen substantially expressed in human lung cancer and that human lung cancer cells expressing GM2 became more susceptible to anti-GM2 monoclonal antibody (mAb)-dependent tumor cell killing mediated by human effector cells after HuIFN-gamma treatment. GM2 expression on human lung cancer cells treated with or without HuIFN-gamma was measured by flow cytometry. The antibody-dependent cellular cytotoxicity (ADCC) activity was assessed by 4-h 51Cr release assay. HuIFN-gamma enhanced GM2 expression on human small-cell lung cancer (SCLC), SBC-3, and human non-small-cell lung cancer (NSCLC), A549 cells in a dose-dependent manner. The optimal concentration of HulIFN-gamma was 1,000 U/ml. The effect of HulFN-gamma reached maximum after 4 days of culture. HulFN-gamma did not have any effect to enhance the expression of other gangliosides in SBC-3 cells. No other cytokines used in this study modulated GM2 expression in SBC-3 cells. Anti-GM2 mAb-dependent ADCC activities induced by lymphocytes and monocytes were more potent against IFN-gamma-treated SBC-3 and A549 cells than nontreated cells. Taken together, HulFN-gamma combined with anti-GM2 mAb may be useful for immunotherapy against GM2-positive human lung cancer.

Humanized anti-ganglioside GM2 antibody is effective to induce antibody-dependent cell-mediated cytotoxicity in mononuclear cells from lung cancer patients

Ganglioside GM2 is one of the major gangliosides expressed on the cell surface of human tumors including lung cancer. We have previously reported that a mouse-human chimeric monoclonal antibody (mAb), KM966, against GM2 promotes the lysis of lung cancer cells by human blood mononuclear cells (MNC) of healthy donors. In this study, we examined antibody-dependent cell-mediated cytotoxicity (ADCC) of MNC, using KM966 mAb and its humanized counterpart, KM8969, in 16 lung cancer patients and 18 control patients. The ADCC activity was assessed by 4-h (51)Cr release from GM2 positive SBC-3 small cell lung cancer cells. MNC from lung cancer patients exhibited similar ADCC activity to those from control patients when KM966 and KM8969 were used as mAb. Moreover, effective ADCC activity was observed even in MNC from advanced lung cancer patients. These observations suggest the potential activity of humanized anti-GM2 mAb (KM8969), as well as chimeric KM966, in biological therapy for lung cancer patients.

Flt3 ligand enhances the immunogenicity of a gag-based HIV-1 vaccine

Liposomes and Flt3 ligand (Flt3L), a ligand for the fms-like tyrosine kinase receptor Flt3/ FLK2, can augment the immune response to an HIV peptide vaccine. The HGP-30 peptide used in these studies is a synthetic peptide that corresponds to a highly conserved region of HIV-1 p17 gag (amino acids 86-115). Mice were immunized with HGP-30 or HGP-30 conjugated to keyhole limpet hemocyanin (KLH) and delayed-type hypersensitivity (DTH) responses, antibody (IgG) amount and antigen-specific proliferative responses by spleen cells were used to monitor the immune response. Daily injections of Flt3L prior to HGP-30 administration enhanced significantly an antigen-specific lymphocyte proliferation response when compared with Flt3L, HGP-30 alone or HGP-30 containing liposomes. Intravenous administration of HGP-30 was superior to intramuscular (i.m.) immunization for the induction of DTH responses. The HGP-30/KLH containing liposomes enhanced both DTH and antibody responses, while liposomes containing HGP-30 peptide elicited only T cell responses. In these studies, either Flt3L or liposomes increased DTH responses compared with the i.m. injection of the HGP-30 vaccine alone.

Comparison of the hematopoietic activity of flt-3 ligand and granulocyte-macrophage colony-stimulating factor acting alone or in combination

The hematopoietic sequelae of intramuscular administration of flt-3 ligand (FL) and granulocyte-macrophage colony-stimulating factor (GM-CSF) alone, or in combination, were compared in BALB/c mice. Changes in hematopoiesis were measured in the marrow, spleen and blood using an in vitro colony-forming unit (CFU) assay and flow cytometrically (expression of CD34 and stem cell antigen (Sca)-1). FL administration was associated with a significant increase in the absolute number of CFU and CD34+ cells in the marrow and CFU, CD34+, Sca-1+, and CD34+ Sca-1+ cells in the spleen and blood. These data demonstrate that FL expands and mobilizes a range of hematopoietic progenitors. By comparison, GM-CSF administration was associated with a significant increase in the number of CFU in the spleen and a significant reduction in marrow CD34+, Sca-1+, and CD34+Sca-1+ cells. These data suggest that GM-CSF-driven expansion of CFU may be at the expense of more primitive cells. The pattern of progenitor cell expansion associated with FL + GM-CSF administration was similar to that of FL alone with the following exceptions. The numbers of spleen and blood CFU were significantly greater and the number of marrow CD34+Sca-1+ cells were significantly less, than with FL alone. These data suggest that co-administration of these cytokines may combine the expansion of the more primitive cell populations (associated with FL) with the expansion of the more mature CFU population (associated with GM-CSF) to yield a greater overall CFU expansion and elevation of CFU in the blood. However, increasing the expansion and mobilization of the relatively mature, rather than the more primitive, hematopoietic progenitors, may be of limited value as a mobilization strategy, if the goal is the expansion and isolation of increased numbers of "high-quality," primitive cells for transplantation.

Therapeutic efficacy of a new topoisomerase I and II inhibitor TAS-103, against both P-glycoprotein-expressing and -nonexpressing drug-resistant human small-cell lung cancer

We examined the effect of a novel topoisomerase I and II (topo I and II) inhibitor, TAS-103, on P-glycoprotein (P-gp)-expressing and -nonexpressing drug-resistant human small-cell lung cancer (SCLC) cells in vitro and in vivo. We observed that TAS-103 was effective in inhibiting in vitro proliferation of human SCLC (SBC-3 and H69) cells and their drug-resistant variants SBC-3/ADM or SBC-3/CDDP and H-69/VP, respectively. SBC-3/ADM and H-69/VP expressed high P-gp, whereas SBC-3/CDDP did not. TAS-103 also effectively reduced the tumor growth (more than 50% inhibition) of the parental as well as MDR SCLC cells grown SC in nude mice. Adriamycin (ADM) and cisplatin (CDDP), on the other hand, were effective only against the parental cells, while these drugs failed to inhibit the respective drug-resistant variants in vitro or in vivo. TAS-103 was observed to induce apoptosis dose dependently in the parental as well as drug-resistant SCLC cells as analyzed after 48 h of in vitro treatment, suggesting that the stabilization of cleavable topo I- or II-DNA complexes by topo I and II inhibitors like TAS-103 is followed by apoptosis of the cells. Overall, our study suggests that TAS-103 may have clinical application against drug-resistant human SCLC.

Cytolysis of human dendritic cells by autologous lymphokine-activated killer cells: participation of both T cells and NK cells in the killing

Dendritic cells (DC) play a key role in the initiation of immune response by stimulating the naive T cells. The fate of DC after the initiation of immune response is not clearly understood. Although there are few reports implicating natural killer (NK) cells in the elimination of DC, killing of DC by LAK cells, and specifically by T cells, has not been studied. In this study, we observed that DC, generated from monocytes, in vitro in the presence of granulocyte-macrophage colony-stimulating factor, interleukin-4 (IL-4), and tumor necrosis factor alpha were susceptible to cytolysis by lymphokine-activated killer (LAK) cells induced in the presence of IL-2 and IL-15 but not IL-12 alone. However, LAK cells induced by a combination of IL-12 and suboptimal dose of IL-2 were cytotoxic to DC. When purified lymphocytes were activated with IL-2, the CD8+/CD57- fraction (T-LAK), but not the CD8-/CD57+ fraction (NK-LAK) was cytotoxic to autologous DC. However, when unseparated peripheral blood mononuclear cells were used to generate LAK cells, both T-LAK and NK-LAK fractions showed equal cytotoxicity against autologous DC. Monoclonal antibodies against CD54, CD11a, and CD18 significantly inhibited the cytolysis, indicating that the killing involves the engagement of CD54 with its ligands.

Differential effect of interleukin 10 on interleukin 12- and interleukin 2-mediated killer induction from blood mononuclear cells

We investigated the regulatory effect of interleukin (IL) 10 on IL-12-inducible killer activity of blood mononuclear cells (MNC) of healthy subjects. IL-10 suppressed non-MHC-restricted killer activity induced by IL-12 in a dose-dependent manner. Cytotoxicity against Daudi cells of blood MNC activated with optimal dose (100 U/ml) of IL-12 was significantly suppressed from 36.6 +/- 6.8% (mean +/- SE) to 26.0 +/- 5.0% by 100 ng/ml of IL-10 (n = 5; P < 0.05) at an E/T ratio of 20. IL-10, however, did not suppress killer induction by IL-2 from blood MNC. On the other hand, IL-4, a known inhibitor of IL-2-mediated killer induction, had no effect on IL-12-mediated killer induction from blood MNC. Moreover, production of interferon-gamma by IL-12-stimulated MNC was suppressed by IL-10. Because the presence of IL-10 is reported in the tumor-growing site, these observations suggest that IL-10 acts as a key cytokine in the suppression of IL-12-mediated antitumor response in situ.

Circumvention of multidrug resistance by a quinoline derivative, MS-209, in multidrug-resistant human small-cell lung cancer cells and its synergistic interaction with cyclosporin A or verapamil

PURPOSE AND METHODS

To develop a clinically useful approach to circumvent P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) in MDR human small-cell lung cancer (SCLC), we examined the ability of a novel quinoline compound, MS-209, to reverse MDR by inhibition of P-gp function in combination with other MDR-reversing drugs using a cytotoxicity assay.

RESULTS

We established MDR human SCLC cells by culture in medium with gradually increasing concentrations of adriamycin (ADM). Compared with the parental human SCLC cells, SBC-3, the MDR variant SBC-3 cells obtained (SBC-3/ADM) were highly resistant to various chemotherapeutic agents due to P-gp expression. MS-209 reversed the resistance to ADM and vincristine (VCR) of SBC-3/ADM and H69/VP cells in a dose-dependent manner. Moreover, MS-209 in combination with cyclosporin A (CsA) or verapamil (VER) synergistically enhanced the antitumor effects of ADM and VCR on SBC-3/ADM cells. MS-209 restored ADM incorporation and this effect was enhanced by CsA and VER, suggesting that these synergistic effects were due to competitive inhibition of P-gp function.

CONCLUSION

MS-209 in combination with CsA or VER might increase the efficacy of these chemotherapeutic agents against MDR human SCLC cells.

Model of malignant pleural effusion of human lung adenocarcinoma in SCID mice

Malignant pleural effusion (PE) is a frequent problem in lung cancer. In this study, we established a model of malignant PE of human adenocarcinoma cells, PC-14, in SCID mice. Intravenously injected PC-14 cells formed colonies in the lungs as early as week 4 after tumor inoculation, and produced bloody PE in all recipient SCID mice by week 8. Pretreatment of SCID mice with anti-mouse IL-2 receptor beta chain antibody (TM-beta 1) to deplete natural killer (NK) cells markedly promoted the production of bloody PE and metastases to multiple organs, such as the lungs, liver, kidneys, and lymph nodes 4 weeks after tumor inoculation. Histological studies indicated that PC-14 cells formed colonies in the lungs, and then invaded the pleura and spread to the pleural cavity. To establish cell lines with a high potential to produce PE, we harvested PE, expanded the tumor cells in vitro, and injected them into SCID mice again. By four in vivo selection cycles in this way we obtained PC-14-PM4 cells, which produce lung metastases and PE earlier than PC-14 cells. The survival of SCID mice inoculated with PC-14-PM4 cells was significantly shorter than that of mice inoculated with PC-14 cells. The expressions of adhesion molecules, such as CD44, CD49d, ICAM-1, and MHC class I, on PC-14-PM4 cells tended to increase compared with PC-14 cells. These changes of adhesion molecules seem to be one of possible mechanisms involved in higher metastatic potential of PC-14-PM4 cells. PE models with PC-14 and PC-14-PM4 cells should be useful for biological and preclinical studies on malignant PE produced by human lung cancer.

Effect of clarythromycin on the distant metastases of human lung cancer cells in SCID mice

Recently, the use of macrolides is suggested to be therapeutically effective in prolonging the survival of patients with inoperable non-small cell lung cancer. The purpose of this study was to examine therapeutic effects of a macrolide, clarythromycin (CAM) on the metastastic developments of two different human non-small cell lung cancers (squamous cell lung carcinoma RERF-LC-AI, and adenocarcinoma PC-14) in severe combined immunodeficient (SCID) mice depleted or undepleted of natural killer (NK) cells, respectively. CAM, injected subcutaneously at doses of 5 and 10 mg/kg body weight/day from day 7 to 41 after i.v. inoculation of human lung cancer cells, was not effective in inhibiting their distant organ metastases in SCID mice. CAM at concentrations of less than 10 micrograms/ml did not have a direct influence on the proliferation of these tumor cells in vitro. Although CAM alone was not effective in augmenting NK activity, it augmented the IL-2-induced killer (LAK) activity against Daudi cells in vitro. These results suggest that CAM alone may not be enough to control the spread of non-small cell lung cancer in the patient with T cell dysfunction.

Ascitic growth of a T cell lymphoma in mice alters the humoral and cellular immune response to exogenous antigens

The effect of the ascitic growth of Dalton's lymphoma (DL), a T cell lymphoma, on the immune responses of the host mice to exogenous antigens, with respect to the humoral response, delayed-type hypersensitivity (DTH) response and the antigen-presenting ability of macrophages was investigated. The humoral immune response to sheep red blood cells (SRBC) as well as the antigen-presenting ability of macrophages (with keyhole limpet hemocyanin as the standard antigen) in the DL-bearing mice were consistently higher than in the normal mice, although the magnitude showed a decline during later tumor stages. However, the DTH response to SRBC was suppressed in the DL-bearing mice compared with the response in the normal mice. The possible mechanisms are discussed. In vivo administration of FK565, a synthetic biological response modifier, enhanced the humoral immune response as well as the antigen-presenting ability of the macrophages in the normal and early DL-bearing mice, whereas these immune responses n the later tumor-bearing animals were found to be nonresponsive to FK565 treatment. In contrast, the DTH response in the normal as well as in the DL-bearing mice was suppressed on FK565 administration. This is the first study of its kind regarding the effect of the ascitic growth of any T cell lymphoma on various aspects of the immune response to exogenous antigens and the correlation thereof with an immunomodulator.

Alteration in IL-1 and arginase activity of tumor-associated macrophages: a role in the promotion of tumor growth

The present investigations were undertaken to study whether the macrophages associated with Dalton's lymphoma (DLAM), a spontaneous T-cell lymphoma, are modulated for the secretion of tumor growth-promoting factors in ascites. The DL ascitic fluid (DLAF) and the culture supernatants of DLAM harvested from mid and late tumor-bearing stages, but not early tumor-bearing stage, enhanced the proliferation of DL cells in vitro. These observations indicate that DLAF contains certain DL growth-promoting substances and at least some of them are secreted by DLAM. The DLAM obtained from mid and late tumor-bearing stages showed enhanced IL-1 production and arginase activity, with a concomitant decline in the RNI production, which could be implicated in the DLAM-mediated promotion of tumor growth.

Effect of cisplatin and FK565 on the activation of tumor-associated and bone marrow-derived macrophages by Dalton's lymphoma

The present investigations were undertaken to study the effect of Dalton's lymphoma (DL) in situ on the functions of DL-associated macrophages (DL-AM) and bone marrow-derived macrophages (BMDM) in C3H/He mice. DL-AM showed enhanced production of reactive nitrogen intermediates (RNI) and tumor necrosis factor (TNF) compared with normal peritoneal macrophages (NMO). BMDM of DL mice also showed enhanced production of RNI compared with BMDM of normal mice. These observations suggest that the presence of DL in situ creates an environment which favours the activation of both DL-AM and macrophage progenitors located at a distant site. The effect of in vivo administration of chemotherapeutic drugs cisplatin and FK565 on the activation of DL-AM by DL cells was also investigated. Both cisplatin and FK565 augmented RNI production of NMO but differed in their effect on DL-AM. The production of RNI by DL-AM of cisplatin-treated mice was inhibited, whereas in the FK565 group it was up-regulated.

Diversity, distribution and host range of mistletoe in protected and unprotected areas of Central Nepal Himalayas

Diversity, distribution and host range of mistletoe were assessed in protected and unprotected areas of the Central Nepal Himalayas. This study recorded ten mistletoe species. Occurrence of all ten mistletoe species within the Shivpuri Nagarjun National Park (SNNP) was a clear indication that national parks provide better habitat for mistletoe species richness and thus a better opportunity for biodiversity conservation than in unprotected areas. For these mistletoes, a total of 34 host species of 21 unrelated families were documented. Scurrula genus of the Loranthaceae family had the highest number of species, the highest number of host species, and the widest altitudinal distribution. Variation in climatic factors, edge effect, disperser behaviour, fragmented forests and the availability of suitable host species determine the occurrence of a particular mistletoe species in a particular habitat. Key words: Diversity: distribution: host range: mistletoe: Nepal DOI: 10.3126/banko.v20i2.4797 Banko Janakari Vol.20(2) 2010 pp.14-20