Cancer Chemoresistance; Recent Challenges and Future Considerations.

Cancer remains one of the serious health hazards and major causes of human mortality across the world. Despite the development of many typical antineoplastic drugs and introduction of novel targeted agents, chemoresistance constitutes a major challenge in the effective therapeutic management of cancer. Drug inactivation, efflux of anticancer agents, modification of target sites, enhanced repair of DNA damage, apoptosis failure and induction of epithelial-mesenchymal transition are the principal mechanisms of cancer chemoresistance. Moreover, epigenetics, cell signaling, tumor heterogeneity, stem cells, microRNAs, endoplasmic reticulum, tumor microenvironment and exosomes have also been implicated in the multifaceted phenomenon of anticancer drug resistance. The tendency of resistance is either intrinsically possessed or subsequently acquired by cancerous cells. From clinical oncology standpoint, therapeutic failure and tumor progression are the most probable consequences of cancer chemoresistance. Combination therapy can help to overcome the issue of drug resistance, and therefore, the development of such treatment regimens is recommended for counteracting the emergence and dissemination of cancer chemoresistance. This chapter outlines the current knowledge on underlying mechanisms, contributory biological factors and likely consequences of cancer chemoresistance. Besides, prognostic biomarkers, diagnostic methods and potential approaches to overcome the emergence of antineoplastic drug resistance have also been described.

The Long-Term Characteristics of Immunity Conferred by COVID-19 Using Antibody Tests.

Introduction Since December 2019, more than 184 Million cases and 3.97 Million COVID-19 related deaths have been reported around the world. Since these statistics are laboratory-based confirmed cases, the true burden of disease may be underestimated. Many populations like those who are regularly visiting health care facilities and those with end-stage renal disease (ESRD) for visiting dialysis units, patients with malignancies, on regular chemo and radiotherapy, and healthcare workers (HCW) are considered high risk for nosocomial COVID-19 re-infections. Objective To understand the long-term behaviour and protective efficacy of already formed anti-SARS-CoV-2 antibody against spike-S protein and nucleocapsid antigen in different populations keeping in view their risk of re-exposure and re-infection is high. To delineate seropositivity with respect to age, gender, and other co-morbidities like diabetes mellitus (DM), hypertension (HTN), and chronic kidney disease (CKD)/ESRD as well as the general population. Methodology During the study, 480 cases of COVID-19 with a post-exposure antibody reactive were followed. These patients were followed on telemedicine for the development of reinfection symptoms and persistence of antibody response. Around 115 patients agreed for regular monitoring of their immunity against the COVID-19 virus through testing through the anti-SARS-CoV-2 antibody test. The rest of the patients were followed on telemedicine until the date of development of any re-infection, but none reported to have typical symptoms of COVID-19 along with positive polymerase chain reaction (PCR). Results Among 115 patients, the mean age was 42.44 + 15.755 years. 61.7% of patients were males and 66.1% were non-health workers while 26.1% of patients had DM/HTN or both. Among these patients, 76.5% had mild/no symptoms and antibodies were found present among 51.3% patients for 3-6 months. Only 2.6% of patients were re-infected. Significant association (p<0.05) of age was found with re-infection while insignificant association (p>0.05) of sex, co-morbidities, profession, symptoms, and persistence of antibodies with re-infection. Conclusion The study concluded that natural immune response was adequate to protect against reinfection as long as more than 9 months. It was more pronounced among patients with ESRD and those with severe disease. Surprisingly, among patients with haematological malignancies, either there was no seropositivity or a very weak positive antibody response. All other malignancies had similar seropositivity behaviour compared to the general population or other co-morbidity like DM, HTN, and coronary artery disease (CAD).

Molecular detection of Strongyloides sp. in Australian Thoroughbred foals.

BACKGROUND: Strongyloides westeri is found in the small intestine of young horses, mainly in foals up to about 16 weeks of age. The main source of infection for foals is through transmammary transmission, and foals can develop acute diarrhoea, weakness, dermatitis and respiratory signs. The epidemiology of S. westeri in Australia is largely unknown. Further, molecular techniques have never been employed for detection of S. westeri in horses. This pilot study aimed to assess the utility of a molecular phylogenetic method for the detection of S. westeri in the faeces of foals. METHODS: Faecal samples were collected from a foal of less than 2 months of age, and eggs of Strongyloides sp. were detected using the modified McMaster technique. DNA was extracted from purified eggs, and a partial fragment of the small subunit of the nuclear ribosomal DNA (18S) was characterised using polymerase chain reaction, DNA sequencing and phylogenetic methods. RESULTS: Microscopic examination of faeces revealed small ellipsoidal eggs typical of Strongyloides sp. The 18S sequence generated by PCR in this study revealed 98.4% identity with that of a reference sequence of S. westeri available from GenBank. Phylogenetic analyses revealed a polyphyletic clustering of S. westeri sequences. CONCLUSION: This is the first study reporting the detection of DNA of Strongyloides sp. in faeces of a foal using a molecular phylogenetic approach targeting the variable region of 18S rDNA. It is anticipated that this study will allow future molecular epidemiological studies on S. westeri in horses.

Clinical Utility of Protein Induced by Vitamin K Absence-II in Patients with Hepatocellular Carcinoma.

OBJECTIVE: Despite moderate sensitivity, alpha fetoprotein (AFP) is widely used in screening and prognostication for hepatocellular carcinoma (HCC). The objective of the current study was to assess clinical utility of Prothrombin induced by Vitamin K absence-II (PIVKAII) in addition to AFP in patients with HCC. METHODS: We retrospectively reviewed 244 patients with documented AFP, PIVKA II and dynamic imaging of the liver. Using ROC curves, cutoff values for AFP and PIVKAII for HCC detection, tumor grade and microvascular invasion (MVI) were assessed. In patients who underwent liver transplantation (LT) for HCC, survival was determined using Kaplan Meier curves. RESULTS: The median PIVKAII in healthy living donors was 28.6mAU/ml (15.9-55). In cirrhotics, the sensitivity of an AFP cutoff of 7.6 ng/ml or PIVKAII  cutoff of 250 mAU/ml for HCC detection was 91.7% (176/192) and specificity was 62.9%(68/108) (p <0.0001). In patients with HCC, PIVKAII values were significantly elevated with tumor size > 5 cm (P < 0.0001), tumor nodules > 3(P=0.01), and macrovascular invasion(p <0.0001).  The high risk group (patients with AFP ≥ 40 ng/ml + PIVKAII ≥ 350 mAU/ml), had a sensitivity of (23/33) 69.6% and specificity of (22/22)100% for MVI (P <0.001). The estimated 3 year RFS after LT in the low risk group (AFP.

Arthroscopic removal of a solitary osteochondroma interfering with the podotrochlear apparatus in a foal.

OBJECTIVE: To report the diagnostics, surgical treatment, and outcome of a juvenile foal with solitary osteochondroma (SO) interfering with the podotrochlear apparatus. STUDY DESIGN: Case report ANIMAL: One 36-day-old Arabian colt. METHODS: Clinical, radiographic, ultrasonographic, computed tomographic, and histopathologic examinations were required to characterize and treat an SO located at the palmar aspect of the diaphysis of the second phalanx of the left forelimb. This SO caused severe distal interphalangeal joint (DIPJ) inflammation, marked interference with the podotrochlear apparatus, and associated lameness. RESULTS: Despite the small size of the foal's foot, complete resection of the SO was possible via palmar DIPJ arthroscopy by using motorized equipment. Full resolution of the lameness was achieved within 3 months of surgery. CONCLUSION: Atypical SO located on the palmar aspect of the second phalanx can cause marked nonseptic inflammation of the DIPJ and interference with the podotrochlear apparatus and should be considered among the differential diagnoses for severe lameness in juvenile foals. Arthroscopic resection of the SO led to an excellent outcome.

An In Vitro Study of the Photodynamic Effectiveness of GO-Ag Nanocomposites against Human Breast Cancer Cells.

Graphene-based materials have garnered significant attention because of their versatile bioapplications and extraordinary properties. Graphene oxide (GO) is an extremely oxidized form of graphene accompanied by the functional groups of oxygen on its surface. GO is an outstanding platform on which to pacify silver nanoparticles (Ag NPs), which gives rise to the graphene oxide-silver nanoparticle (GO-Ag) nanocomposite. In this experimental study, the toxicity of graphene oxide-silver (GO-Ag) nanocomposites was assessed in an in vitro human breast cancer model to optimize the parameters of photodynamic therapy. GO-Ag was prepared using the hydrothermal method, and characterization was done by X-ray diffraction, field-emission scanning electron microscope (FE-SEM), transmission Electron Microscopy (TEM), energy dispersive X-rays Analysis (EDAX), atomic force microscopy and ultraviolet-visible spectroscopy. The experiments were done both with laser exposure, as well as in darkness, to examine the phototoxicity and cytotoxicity of the nanocomposites. The cytotoxicity of the GO-Ag was confirmed via a methyl-thiazole-tetrazolium (MTT) assay and intracellular reactive oxygen species production analysis. The phototoxic effect explored the dose-dependent decrease in the cell viability, as well as provoked cell death via apoptosis. An enormously significant escalation of ¹O2 in the samples when exposed to daylight was perceived. Statistical analysis was performed on the experimental results to confirm the worth and clarity of the results, with p-values < 0.05 selected as significant. These outcomes suggest that GO-Ag nanocomposites could serve as potential candidates for targeted breast cancer therapy.

Two unusual cases of generalized Coenurus gaigeri cyst infection in Beetal goats.

In the present communication, two unusual cases of generalized Coenurus gaigeri cyst infection in goats presented at Veterinary Teaching Hospital, University of Agriculture Faisalabad, Pakistan has been documented. Clinical (Case I) and postmortem (Case II) findings along with micro and macroscopic examination of excised cysts supported the diagnosis.

Serum Neopterin: A Potential Marker for Screening Blood Donors.

OBJECTIVE: To determine serum neopterin levels in blood donors of local population and its association with transfusion transmitted infections. STUDY DESIGN: A cross-sectional observational study. PLACE AND DURATION OF STUDY: Department of Physiology, Liaquat National Hospital and Medical College (LNHMC) in collaboration with Basic Medical Sciences Institute (BMSI) and Jinnah Postgraduate Medical Centre (JPMC), Blood Bank, Karachi, Pakistan, from January to June 2015. METHODOLOGY: During this period, a total of 174 blood donors were selected through random sampling technique. All participants fulfilling the inclusion criteria involving apparently healthy blood donors of either gender within the age bracket of 18 - 60 years and consenting to participate were selected. The participants were screened for transfusion transmitted infections as per WHO recommendations through the standard procedures used for screening at the JPMC blood bank. The demographic profile, anthropometric measurements and vitals were recorded for every participant. Serum neopterin was measured using ELISA kits. Data was analysed on SPSS version 21. ANOVA and chi-square tests were applied as tests of significance at a p-value of <0.05. RESULTS: The neopterin content in the sera of disease negative blood donors was 6.23 ±2.19 nmol/l as compared to disease positive blood donors, in whom the neopterin level was increased to 15.10 ±4.93 nmol/l (p =0.001). CONCLUSION: The neopterin assay has the potential to detect a number of transfusion transmissible viral diseases; which may, or may not be revealed by the usually employed battery of routine tests. We conclude that the risk of transfusion transmitted pathogens in our population can be reduced significantly, using neopterin assay as a routine in blood banks.

Massive attack by honeybees in a German shepherd dog: description of a fatal case and review of the literature

In the present study, a fatal case caused by honeybee (Apis cerana) stings was documented in a female German shepherd dog that was presented at the Veterinary Teaching Hospital, University of Agriculture Faisalabad, Pakistan. Characteristic clinical signs included hematuria, hematemesis, incoordination and convulsions along with evidence of massive honeybee attack supported the diagnosis of envenomation. The dog was treated with dexamethasone and diphenhydramine, but it did not respond to therapy and died. This outcome could be avoided if we had a bee antivenom available for treating envenomated patients.(AU)

Massive attack by honeybees in a German shepherd dog: description of a fatal case and review of the literature

In the present study, a fatal case caused by honeybee (Apis cerana) stings was documented in a female German shepherd dog that was presented at the Veterinary Teaching Hospital, University of Agriculture Faisalabad, Pakistan. Characteristic clinical signs included hematuria, hematemesis, incoordination and convulsions along with evidence of massive honeybee attack supported the diagnosis of envenomation. The dog was treated with dexamethasone and diphenhydramine, but it did not respond to therapy and died. This outcome could be avoided if we had a bee antivenom available for treating envenomated patients.