Artisanal small-scale mining is widely operated in various countries serving as a livelihood to many rural communities. However, it is a significant source of environmental mercury contamination which affects human health. Amalgamation and amalgam smelting, two significant steps in the artisanal small-scale mining operations generate lots of mercury vapors, leading to chronic exposure among miners. Thus, this article seeks to provide a topical review of recent findings on organ damage and metabolic disorders among mercury-exposed artisanal small-scale miners with emphasis on the contributing factors such as personal protective equipment usage and artisanal small-scale gold mining-specific occupational activities. Also, insights into the effect of mercury intoxication and mechanisms of action on organ and metabolic systems among exposed individuals are provided.

The mitochondria are defined by their unique structure and cellular functions which includes energy production, metabolic regulation, apoptosis, calcium homeostasis, cell proliferation, cell motility and transport as well as free radical generation. Recent advances geared towards enhancing the diagnostic and prognostic value of cancer patients have targeted the circulating mitochondria genome due to its specific and unique characteristics. Circulating mitochondria DNA is known to possess short length, relatively simple molecular structure and a high copy number. These coupled with its ability to serve as a liquid biopsy makes it an easily accessible non-invasive biomarker for diagnostics and prognostics of various forms of solid tumors. In this article, we review recent findings on circulating mitochondria DNA content in cancer. In addition, we provide an insight into the potential of circulating mitochondria DNA to act as a non-invasive diagnostic biomarker and its linearity with clinical and sociodemographic characteristics.

Chemotherapy is one of the main therapeutic strategies used for gastrointestinal tract adenocarcinomas (GTAs), but resistance to anticancer drugs is a substantial obstacle in successful chemotherapy. Accumulating evidence shows that non-coding RNAs, especially long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), can affect the drug resistance of tumor cells by forming a ceRNA regulatory network with mRNAs. The efficiency of the competing endogenous RNAs (ceRNAs) network can be affected by the number and integrality of miRNA recognition elements (MREs). Dynamic factors such as RNA editing, alternative splicing, single nucleotide polymorphism (SNP), RNA-binding proteins and RNA secondary structure can influence the MRE activity, which may in turn be involved in the regulation of chemoresistance-associated ceRNA network by prospective approaches. Besides activities in a single tumor cell, the components of the tumor micoenvironment (TME) also affect the ceRNA network by regulating the expression of non-coding RNA directly or indirectly. The alternation of the ceRNA network often has an impact on the malignant phenotype of tumor including chemoresistance. In this review, we focused on how MRE-associated dynamic factors and components of TME affected the ceRNA network and speculated the potential association of ceRNA network with chemoresistance. We also summarized the ceRNA network of lncRNAs, miRNAs, and mRNAs which efficiently triggers chemoresistance in the specific types of GTAs and analyzed the role of each RNA as a "promoter" or "suppressor" of chemoresistance.

Background. Despite the recent advancement in diagnostic methods, the smear microscopy remains the gold standard for the diagnosis of pulmonary tuberculosis in high burden countries like Ghana. Notwithstanding, fluorescence staining technique provides a more efficient option for the detection of Mycobacterium tuberculosis positive smears. This study therefore aimed at assessing the diagnostic performance of fluorescence microscopy (FM) and Ziehl-Neelsen (ZN) staining techniques in the diagnosis of pulmonary tuberculosis. Methods. A comparative study was carried out on 100 patients who reported at the Out Patients Department (OPD) or the Directly Observed Therapy (DOT) center of the Kade Government Hospital and were suspected of having pulmonary tuberculosis. Two (2) sputum samples each were collected. This included one spot and one morning sample. The smears were prepared and stained with FM and ZN staining techniques. Xpert MTB/RIF assay was also performed. Results. Of the 200 samples analyzed, 71 (35.5%), 46 (23.0%), and 84 (42.0%) were positive for pulmonary tuberculosis when FM, ZN, and XPERT MTB/RIF assays were used, respectively. The mean reading time of FM was three times faster than the ZN technique with very good acceptance (1.5min: 4.6min). The sensitivity and specificity of fluorescent staining to that of XPERT MTB/RIF assay were 84.5% and 100%, respectively, while those of ZN staining were 54.8% and 100%, respectively. Conclusion. For a routine laboratory test in a resource-limited setting, our study has demonstrated that fluorescence staining technique is a more sensitive test for the diagnosis of pulmonary tuberculosis as compared to the conventional ZN technique.

Mercury is a toxic metal with its effects on human health ranging from acute to chronic in a very short time of exposure. Artisanal and small-scale gold mining (ASGM) is the main source of direct human exposure to mercury. To access the effect of mercury exposure on the renal function and level of personal protective equipment (PPE) compliance among small-scale gold miners in Bibiani District of the Western Region of Ghana 110 consenting male gold miners were purposively recruited for this study. A structured questionnaire was used to collect socio-demographic information from the participants. Work place assessment and interviews were conducted. Urine samples were analysed for protein; blood was analysed for mercury and creatinine. Estimated glomerular filtration rate (eGFR) was calculated using the chronic kidney disease-epidemiology collaboration (CKD-EPI) equation. Of the 110 participants, 61(55.5%) exceeded the occupational exposure threshold (blood mercury <5μg/L). Urine protein (41.72±68.34, P<0.0001), serum creatinine (2.24±1.19, P<0.0001) and blood mercury (18.37±10.47, P<0.0001) were significantly elevated among the exposed group compared to the non-exposed group. However, the exposed group had a significantly reduced eGFR (P<0.0001). There was a significant correlation (r=0.7338, p<0.0001) between blood mercury concentration and urine protein concentration. An increase in blood mercury correlated negatively (r = −0.8233, P<0.0001) with eGFR among the exposed group. High urine protein (P< 0.0001) and high serum creatinine (P< 0.0001) were significantly associated with increased mercury exposure. Increased mercury exposure was significantly associated with burning of amalgam (P=0.0196), sucking of excess mercury (P=0.0336), longer work duration (P=0.0314) and low educational background (P=0.0473). Small scale miners at the Bibiani work site are exposed to excess mercury. Proteinuria and reduced eGFR is common in mine workers exposed to excess mercury. We found poor PPE compliance among the study population.

Mercury can be very toxic to human health even at low dose of exposure. Artisanal small-scale miners (ASGMs) use mercury in gold production, hence are at risk of mercury-induced organ dysfunction. We determined the association between mercury exposure, thyroid function and work-related factors among artisanal small-scale gold miners in Bibiani- Ghana. We conveniently recruited 137 consenting male gold miners at their work site in Bibiani-Ghana, in a comparative cross-sectional study. Occupational activities and socio-demographic data of participants were collected using a questionnaire. Blood sample was analysed for total mercury and thyroid hormones. Overall, 58.4% (80/137) of the participants had blood mercury exceeding the occupational exposure threshold (blood mercury ≥5μg/L). T3(P<0.0001) and T4(P<0.0001) were significantly reduced among the exposed group compared to the non-exposed. TSH showed no significant variation between the exposed and non-exposed groups. Longer work duration (≥5years), gold amalgamation, gold smelting and sucking of excess mercury with the mouth were associated with increased odds of mercury exposure. Blood mercury showed negative correlation with T3(r = -0.29, P<0.0001), and T4(r = -0.69, P<0.0001) and positive correlation with work duration (r = 0.88, P<0.001). Even though a positive trend of association between blood mercury and TSH levels was recorded, it was not significant (r = 0.07, P = 0.4121) Small scale miners in Bibiani are exposed to mercury above the occupational threshold which may affect thyroid hormone levels.