An investigation into marine bacterial species found in shark mouths in the Indian Ocean and their implications for human health.

M. Med. Sc. University of KwaZulu-Natal, Durban 2015.There is an ever increasing amount of pollution and waste being released into the environment. This is due to the increase in population, urbanisation and people migrating into cities. Approximately 2.4 billion people living in urban and rural areas have no access to basic sanitation. In the next 20 years, there will be a further increase of 2 billion people who will lack basic sanitation. In developing countries, 90% of untreated sewage is released into rivers, lakes and coastal waters. Apart from sewage, waste such as petroleum products, heavy metals and organochlorine also contribute to marine pollution. Companies that manufacture sugar/artificial sweeteners etc. and farming activities that utilize fertilizers for crops can cause eutrophication, as un-used fertilizers get washed into rivers. The marine water is a different environment to other aquatic and terrestrial environments. This then forces microbes to adapt, so they can be able to survive in the marine environment. The difference in the marine environment allows for the production of distinct bioactive metabolites such as secondary metabolites. These secondary metabolites come from algae and marine bacteria and these secondary metabolites are then exclusive to the marine waters. These secondary metabolites can be used for medical purposes, cosmetics, personal-care products etc. There is a huge problem with antibiotic resistance and research needs to be done to solve this resistance issue. Two common bacterial strains were isolated and identified from the mouth of sharks. The bacteria were identified as Bacillus cereus and Vibrio alginolyticus. They were isolated and cultured in broth for 3 days, till they reached the log phase of growth. The broth was then extracted for metabolites which the bacteria produced, using ethyl acetate. These metabolites were tested for cytotoxicity in the human liver hepatocellular carcinoma (Hep G2) cells. The concentrations that were determined to cause 50% cell death (IC50) in the cell viability assay on Hep G2 cells were 0.764 mg/ml and 0.918 mg/ml for B. cereus and V. alginolyticus, respectively. These values were then used for subsequent assays. Antibacterial testing was done for the bacterial extracts of Bacillus cereus and Vibrio alginolyticus. There was no antibacterial activity against Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa ATCC 27853. Assays that used flow cytometry was used to show if apoptosis/necrosis occurred. These were assays such as Annexin V and propidium staining. While assays that used luminometry showed the levels of ATP and determined whether apoptosis of the cells occurred. These were assays such as the ATP assay, mitochondrial depolarisation assay and determination of the caspase activities of caspase 3/7, 8 and 9. Additional assays, like the comet and TBARS assays, were done to show DNA fragmentation and oxidative stress of the cells, respectively. The results for the Annexin V/ propidium staining showed the control had a mean of 11.20 ± 1.0. Extract 1 (20.83 ± 0.8737) and extract 2 (25.37 ± 1.050) showed a higher percentage when compared to the control. Extract 2 was significant against the control (p<0.0273). For propidium staining, the control had a mean of 6.033 ± 0.4524. Extracts 1(11.57 ± 1.387) and 2 (11.43 ± 0.3215) showed a higher percentage when compared to the control. The Annexin V and propidium staining suggested that extract 1 and 2 had undergone both apoptosis and necrosis. For luminometry assays, the ATP assay showed that the control had a mean of 1.83x106 ± 5.82x104. Extracts 1 (1.5x106 ± 9.4x104) and extract 2 (1.4x106 ± 8.3x104) showed a decrease in ATP with reference to the control. In the mitochondrial depolarisation assay, the control had a mean of 14.83 ± 1.350. Extracts 1 (30.57 ± 0.75) and extract 2 (20.53 ± 8.56) showed a decrease in polarisation with reference to the control. For caspase 8 analysis, the control, extract 1 and extract 2 had means that were 4.23x104 ± 3.37x103, 52x103 ± 10.1x103 and 40x103±5.2x103, respectively. For caspase 9 analysis, the control, extract 1 and extract 2 had means that were 8.6x104 ± 4.6x103, 5.6x104 ± 4x103and 9.6x104 ± 5.6x104, respectively. The caspase 3/7 analysis showed that the control, extract 1 and extract 2 had means of 4.4x103 ± 0.57x103, 5.5x103 ± 0.19x103 and 5.8x103 ± 2 x103, respectively. Caspase 3/7 showed that apoptosis had occurred with the cells for all extracts used. Extract 1 showed a high caspase activity for caspase 8. This suggested that it followed the extrinsic pathway of apoptosis. Extracts 2 showed a high activity for caspase 9 which suggested that it followed the intrinsic pathway of apoptosis. The comet assay showed that the means of the control, extract 1 and extract 2 were 35.91 ± 21.93, 75.85 ± 11.43 and 60.48 ± 11.86, respectively. The extracts were significantly higher than the control (extract 1 and 2 p<0.0001). Extract 1 and 2 were compared to each other and had shown a significance between them (p<0.0001). The TBARS assay obtained the following MDA concentrations for the control, extract 1, extracts 2, negative and positive samples: 0,137, 0,132, 0,150, 0,088 and 20,502, respectively. The MDA concentration gives an indication of oxidative stress of the cells. From the cell viability assay, the secondary metabolites produced by B. cereus needed a lower concentration of extract to determine an IC50 value. This suggested that the secondary metabolites produced by B. cereus were more toxic than the secondary metabolites produced by V. alginolyticus. This was then further supported by assays such as mitochondrial depolarisation and the comet assay. The secondary metabolites that could be the reason why there were apoptosis and necrosis, are the toxins the bacteria produce. This is the enterotoxin or cereulide produced by B. cereus and TLH by V. alginolyticus. However, further studies need to be done to confirm if these toxins are the cause of cell death

Sequential tendon ruptures in ochronosis: case report

Alkaptonuria is a rare autosomal recessive disorder characterised by the absence of homogentisic acid oxidase, due to deficiency of an enzyme that degrades HGA in the tyrosine degradation pathway. Homogentisic acid (HGA) and its metabolites accumulate in the connective tissues leading to dark pigmentation of connective tissue in patients with alkaptonuria. HGA deposits in connective tissue causes weakness of the tendon and subsequent rupture, especially the large tendons in the body. Only few cases are reported in the literature with multiple tendon rupture but many case reports are available with isolated rupture of tendons. We report on a patient with sequential tendon ruptures in a patient. The case is reported for its rarity

Extensor indicis proprius to extensor pollicis longus transfer in spontaneous rupture of extensor pollicis longus following non displaced fracture distal end radius

Exact incidence of extensor pollicis longus (EPL) ruptures following distal radius fracture is not known. Peculiarly it’s common in nondisplaced fracture of the distal radius with an incidence of EPL rupture of 0.2-5%. Cortical irregularities from distal radius fractures or osteophytes easily abrade the tendon, causing gradual attrition and ultimately rupture. Compromised blood supply is also related to EPL rupture which is supported by microcirculatory anatomic studies. We present a case of 49 year old female who presented with spontaneous rupture of the EPL following a nondisplaced fracture of the distal radius managed by extensor indicis proprius (EIP) transfer. EIP transfer gives promising outcome. Optimum tension of the tendon is crucial for good functional outcome. We recommend suturing the tendon with thumb in extension and wrist in neutral position for optimum tension of tendon to avoid extensor lag and to prevent loss of IP flexion

FUNCTIONAL ANALYSIS OF MEDICINAL PLANTS USING SYSTEMS BIOLOGY APPROACHES

Plant derived medicine is an important source of life saving drugs, but the genome information of most important medicinal plants is still unavailable. The need of the hour is to identify more functional genes and enzymes that control secondary metabolite production in medical plants, develop new methods for systematics, engineer resistance to number of biotic and abiotic stresses, and develop new conservation strategies, more genomics, proteomics and metabolomics information needs to be produced. In this review, a brief overview of various omic technologies and its applications to medicinal and aromatic plants are discussed.Â

Challenges and outcome of total hip arthroplasty in patients with developmental dysplasia of the hip: a clinical series with a spectrum of disease manifestation and technical notes

Patients with developmental dysplasia of hip eventually lead on to secondary osteoarthritis in adulthood and may end up with total hip arthroplasty at a younger age. Because of the altered anatomy of dysplastic hips, total hip arthroplasty in these patients is a technically demanding procedure. Altered anatomy of the acetabulum and proximal femur together with leg length discrepancy pose challenges during total hip arthroplasty. Since the majority of the patients are in the younger age group, soft tissue balance is of great importance to maximise postoperative functional result and longevity of prosthesis. In this paper, we present a series of our patients with a spectrum of disease manifestation from mild to severe form and also discuss the associated challenges and the technical solutions and their outcome

Automated skin lesion segmentation using multi-scale feature extraction scheme and dual-attention mechanism

Segmenting skin lesions from dermoscopic images is essential for diagnosing skin cancer. But the automatic segmentation of these lesions is complicated due to the poor contrast between the background and the lesion, image artifacts, and unclear lesion boundaries. In this work, we present a deep learning model for the segmentation of skin lesions from dermoscopic images. To deal with the challenges of skin lesion characteristics, we designed a multi-scale feature extraction module for extracting the discriminative features. Further in this work, two attention mechanisms are developed to refine the post-upsampled features and the features extracted by the encoder. This model is evaluated using the ISIC2018 and ISBI2017 datasets. The proposed model outperformed all the existing works and the top-ranked models in two competitions

Simple and effective method to protect from toxic fumes of methyl methacrylate (bone cement) in operation theatre

Methyl methacrylate is a monomer of acrylic resin widely used in a variety of medical, dental, and industrial applications. Its extensive use in surgery, particularly for arthroplasties, has often raised concerns regarding potential human toxicity for orthopaedic surgeons, surgical nurses, and other operating-room staff who are occupationally exposed to the compound

Plasma CXCL13 but Not B Cell Frequencies in Acute HIV Infection Predicts Emergence of Cross-Neutralizing Antibodies

Immunological events in acute HIV-1 infection before peak viremia (hyperacute phase) may contribute to the development of broadly cross-neutralizing antibodies. Here, we used pre-infection and acute-infection peripheral blood mononuclear cells and plasma samples from 22 women, including 10 who initiated antiretroviral treatment in Fiebig stages I–V of acute infection to study B cell subsets and B-cell associated cytokines (BAFF and CXCL13) kinetics for up to ~90 days post detection of plasma viremia. Frequencies of B cell subsets were defined by flow cytometry while plasma cytokine levels were measured by ELISA. We observed a rapid but transient increase in exhausted tissue-like memory, activated memory, and plasmablast B cells accompanied by decline in resting memory cells in untreated, but not treated women. B cell subset frequencies in untreated women positively correlated with viral loads but did not predict emergence of cross-neutralizing antibodies measured 12 months post detection of plasma viremia. Plasma BAFF and CXCL13 levels increased only in untreated women, but their levels did not correlate with viral loads. Importantly, early CXCL13 but not BAFF levels predicted the later emergence of detectable cross-neutralizing antibodies at 12 months post detection of plasma viremia. Thus, hyperacute HIV-1 infection is associated with B cell subset changes, which do not predict emergence of cross-neutralizing antibodies. However, plasma CXCL13 levels during hyperacute infection predicted the subsequent emergence of cross-neutralizing antibodies, providing a potential biomarker for the evaluation of vaccines designed to elicit cross-neutralizing activity or for natural infection studies to explore mechanisms underlying development of neutralizing antibodies

Plasma CXCL13 but Not B Cell Frequencies in Acute HIV Infection Predicts Emergence of Cross-Neutralizing Antibodies

Immunological events in acute HIV-1 infection before peak viremia (hyperacute phase) may contribute to the development of broadly cross-neutralizing antibodies. Here, we used pre-infection and acute-infection peripheral blood mononuclear cells and plasma samples from 22 women, including 10 who initiated antiretroviral treatment in Fiebig stages I–V of acute infection to study B cell subsets and B-cell associated cytokines (BAFF and CXCL13) kinetics for up to ~90 days post detection of plasma viremia. Frequencies of B cell subsets were defined by flow cytometry while plasma cytokine levels were measured by ELISA. We observed a rapid but transient increase in exhausted tissue-like memory, activated memory, and plasmablast B cells accompanied by decline in resting memory cells in untreated, but not treated women. B cell subset frequencies in untreated women positively correlated with viral loads but did not predict emergence of cross-neutralizing antibodies measured 12 months post detection of plasma viremia. Plasma BAFF and CXCL13 levels increased only in untreated women, but their levels did not correlate with viral loads. Importantly, early CXCL13 but not BAFF levels predicted the later emergence of detectable cross-neutralizing antibodies at 12 months post detection of plasma viremia. Thus, hyperacute HIV-1 infection is associated with B cell subset changes, which do not predict emergence of cross-neutralizing antibodies. However, plasma CXCL13 levels during hyperacute infection predicted the subsequent emergence of cross-neutralizing antibodies, providing a potential biomarker for the evaluation of vaccines designed to elicit cross-neutralizing activity or for natural infection studies to explore mechanisms underlying development of neutralizing antibodies

Nest orientation of Asian giant honeybee, Apis dorsata in plains of Karnataka, India

The giant honeybee, Apis dorsata build nests on both natural and manmade structures by orienting their nests towards different directions. The observations revealed that, the giant honeybee colonies were well distributed on tall buildings, trees and rock cliffs and orientated their nests towards Northeast direction in greater numbers. However, the nests built on trees and rock cliffs showed better orientation towards Northeast and East-West directions respectively. A. dorsata also showed differential levels of nest orientation when distributed individually and in groups. Comparatively, the bee nests were oriented towards Northeast and Southwest direction on buildings and North-South and Northwest direction on trees on distribution of colonies both individually and in groups. However, on rock cliffs, irrespective of individual or group distribution, the nests were oriented towards East-West direction in large numbers. Results revealed concluded that, A. dorsata colonies orient their nests towards all compass directions but they preferred Northeast direction on buildings, North-South on trees and East-West direction on rock cliffs in plains of South Karnataka, India