Anatomical variation of habitat related changes in scapular morphology

The mammalian forelimb is adapted to different functions including postural, locomotor, feeding, exploratory, grooming and defense. Comparative studies on morphology of the mammalian scapula have been performed in an attempt to establish the functional differences in the use of the forelimb. In this study, a total of 102 scapulae collected from 66 species of animals, representatives of all major taxa from rodents, sirenians, marsupials, pilosa, cetaceans, carnivores, ungulates, primates and apes were analyzed. Parameters measured included scapular length, width, position, thickness, area, angles and index. Structures included supraspinous and infraspinous fossae, scapular spine, glenoid cavity, acromium and coracoid processes. Images were taken using computed tomographic (CT) scanning technology (CT-Aquarium, Toshiba and micro CT- LaTheta, Hotachi, Japan) and measurement values acquired and processed using Avizo computer software and CanvasTM 11 ACD systems. Statistical analysis was performed using Microsoft Excel 2013. Results obtained showed that there were similar morphological characteristics of scapula in mammals with arboreal locomotion and living in forest and mountainous areas but differed from those with leaping and terrestrial locomotion living in open habitat or savannah. The cause for the statistical grouping of the animals signifies presence of the close relationship between habitat and scapular morphology and in a way that corresponds to type of locomotion and speed. The morphological characteristics of the scapula and functional interpretation of the parameters in relation to habitat of each taxon is discussed in detail. Keywords: Mammalian, Scapula, Morphology, CT analysi

Potential role of Cytotoxic T-Lymphocyte Antigen 2 alpha in secretory activity of endocrine cells in mouse adenohyphphysis

The peptide hormones of the adenohypophysis are produced by proteolytic processing of their prohormone precursors. Cathepsin L is known to function as a major proteolytic enzyme involved in the production of the peptide hormones. The structure of the propeptide region of cathepsin L is identical to cytotoxic T-lymphocyte antigen-2 alpha (CTLA-2α) which is also shown to exhibit selective inhibitory activities against cathepsin L. However, the specific cell types synthesizing CTLA-2α in mouse adenohypophysis and its functional implications as relevant in vivo have not been demonstrated. In this study, CTLA-2α expression in the adenohypophysis was evaluated by immunohistochemistry. In both male and female mice, strong immunoreactivity was specifically detected in folliculostellate (FS) cells surrounding endocrine cells which were delineated by CTLA-2α. These findings suggest that the CTLA-2α may be involved in the proteolytic processing and secretion of the hormones in the adenohypophysis through regulation of cathepsin L

Expression of cytotoxic T-lymphocyte antigen 2 alpha in mouse bronchiolar epithelial cells: anatomical and functional implications

The lung is one of the major sites of cathepsins (B, H, and L) expression where they are involved in several functions including degradation of extracellular matrix proteins, remodelling of the lung tissue and processing of the invariant chain of the MHC class II complex. Under pathological conditions, cathepsins have been observed in inflammation, tumour progression and metastasis. The enzymatic activity of cathepsins is regulated by changes in pH and their interaction with inhibitors. One of the potent and specific inhibitors of cathepsin L is the Cytotoxic T-lymphocyte antigen-2α (CTLA-2α) which was originally expressed in mouse activated T-cells and mast cells. However, the cellular localization and distribution pattern of CTLA-2α in the lung is not known. In this study, CTLA-2α expression in the lung was evaluated by immunofluorescence. Strong immunoreactivity was specifically detected in the bronchiolar epithelial cells of primary, secondary and terminal segments; moderate in the lymphoid nodules and scanty in the lung parenchyma. The distribution pattern implicates an important role of this inhibitor protein in relation to matrix remodelling, immune response and their relationship to lung development and diseases

Immunoreactivity of Cytotoxic T-Lymphocyte Antigen 2 alpha in mouse pancreatic islet cells.

Cells of the pancreatic islets produce several molecules including insulin (beta cells), glucagon (alpha cells), somatostatin (delta cells), pancreatic polypeptide (PP cells), ghrelin (epsilon cells), serotonin (enterochromaffin cells), gastrin (G cells) and small granules of unknown content secreted by the P/D1 cells. Secretion mechanism of some of these molecules is still poorly understood. However, Cathepsin L is shown to regulate insulin exocytosis in beta cells and activate the trypsinogen produced by the pancreatic serous acini cells into trypsin. The structure of the propeptide region of Cathepsin L is homologous to Cytotoxic T-lymphocyte antigen-2 alpha (CTLA-2 alpha) which is also shown to exhibit selective inhibitory activities against Cathepsin L. It was thought that if CTLA-2 alpha was expressed in the pancreas; then, it would be an important regulator of protease activation and insulin secretion. The purpose of this study was, therefore, to examine by immunohistochemistry the cellular localization and distribution pattern of CTLA-2 alpha in the pancreas. Results showed that strong immunoreactivity was specifically detected in the pancreatic islets (endocrine pancreas) but not in the exocrine pancreas and pancreatic stroma. Immunostaining was further performed to investigate more on localization of Cathepsin L in the pancreas. Strong immunoreactivity for Cathepsin L was detected in the pancreatic islets, serous cells and the pancreas duct system. These findings suggest that CTLA-2 alpha may be involved in the proteolytic processing and secretion of insulin through regulation of Cathepsin L and that the regulated inhibition of Cathepsin L may have therapeutic potential for type 1 diabetes

Comparative gross and histological morphology of goat (caprine) and sheep (ovine) placentomes

This study aimed to investigate the gross and micro-anatomy of the placentome of Tanzanian goats and sheep and their relationship with some foetal parameters. Forty pregnant uteri (20 from goats and 20 from sheep) were collected from slaughtered pregnant animals. Foetal age was estimated using Crown-Rump Length formula. Other parameters such as head length (HL), neck length (NL), fore and hind limb length, foetal weight, total number of placentomes and placentome size and location in the uteri were taken. All placentae exhibited the typical characteristics of a cotyledonary with discrete areas of attachment between maternal and foetal tissues. Placentome counts ranged from 70 to 92 and 74 to 104 in  sheep and goats, respectively. The average length of placentomes was 20.0±4.2 and 30.7±9.0 in sheep and goats, respectively. Placentomes from does in the present study were concave in shape and the majority were of type A. Regression analysis showed a statistically significant relationship  between foetal age and placental size (r2=0.3245; p<0.001); between foetal age and foetal weight (r2=0.7364; p<0.001); and between foetal age and placental weight (r2=0.6458; p<0.01); but the number of placentomes insignificantly (P>0.01) varied with foetal age. In conclusion, this study has demonstrated that the Tanzanian sheep and goat placentae are cotyledonary – synepitheliochorial type having placentomes that tend to increase in  size with gestation age in response to greater nutrient and or metabolic requirement of the growing foetus. &nbsp

Patterns and variations in morphology of glenoid cavity in mammals:Implications for locomotion efficiency

The aim of this study was to evaluate and compare the morphology and dimensions of glenoid cavity and examine their relationship with body size and locomotion efficiency. The study was performed on 356 glenoid cavities from 178 mammals, representatives of all major taxa from rodents, sirenians, marsupials, pilosa, cetaceans, carnivores, ungulates, primates and apes. Parameters measured included cranio-caudal and lateral-medial diameters and their ratios; areas of articular surfaces; glenoid cavity index; angles-alpha, -beta and -gamma and length of supraglenoid tubercle and coracoid process. Images were taken using computed tomographic (CT) scanning technology (CT-Aquarium, Toshiba and micro CT- LaTheta, Hotachi, Japan) and measurement values were acquired and processed using Avizo computer software and CanvasTM 11 ACD systems. Statistical analysis was performed using Microsoft Excel 2013. Results obtained showed that mammals exhibit various patterns in the morphology of glenoid cavities that may be associated with adaptation of the glenohumeral joint to robust mobility for locomotion. When the diameters of glenoid cavities were compared between groups of mammals, significant difference was observed in diameters of articular surfaces between rodents and ungulates (1.34±0.32); carnivores and primates (1.39±0.16); primates and rodents and carnivores (1.3±0.12) and between ungulate and carnivores, rodents and primates (1.19±0.18). The mean values of glenoid cavity index in ungulates were found to be lower (0.15±0.13) than those of carnivores (0.22±0.71) and apes (0.26±0.16), indicating that the depth of glenoid cavities of ungulates is shallow compared to those of carnivores and apes. The inclination of the scapula relative to the trunk was found to be tilted lateromedially in apes; mediolaterally in primates (monkeys); craniocaudally in carnivores; vertically in ungulates and cranially in diggers. Significantly, the angles were wider in apes but narrower in ungulates. The length of supraglenoid tubercle was long in ungulates but short in carnivores while the coracoids process was short in ungulates but long in primates and moderately in carnivores and other mammals. The morphological characteristics of the glenoid cavities and the functional interpretation of the parameters in mammals are discussed in detail

Propeptide-like cysteine protease inhibitors: Structural properties, Mechanisms of inhibition and emerging roles in biological tissues

Current topics in Peptide & Protein research, 2016; 17 (2016): 71-82Propeptides of cysteine proteases including papain and cathepsins B, K, L, and S are selective inhibitors of their cognate cysteine proteases. A new class of endogenous inhibitors homologous to the propeptide regions of cysteine proteases has been identified and characterized in the past few decades. These include the mouse cytotoxic T-lymphocyte antigen-2 (CTLA-2), Bombyx cysteine proteinase inhibitor (BCPI), Drosophila crammer, and salmon salarin. They have been categorized as I29 (CTLA family) in the MEROPS peptidase database. In this review, we summarized experimental findings on their molecular forms, inhibition mechanisms, and biological functions. The overall properties of these inhibitors, molecular structures and inhibition mechanisms were found to be similar to those of propeptides of cysteine proteases. CTLA-2 has been shown to possess a unique inhibition mechanism by blocking its cognate enzyme, cathepsin L, through oxidizing the active thiol residue of the enzyme with its own thiol residue. The divergent biological functions of these inhibitors have been determined based on their inhibitory activities towards cathepsin L-like cysteine proteases. CTLA-2 is strongly expressed in the placenta, and may play roles in implantation and decidualization. It is also an inducer of Treg cells in the eyes, and has been shown to induce apoptosis in murine T-lymphoma cells and cardiac fibroblasts. In the brain, CTLA-2 transcript is strongly expressed in neuronal cell bodies while the protein is localized in dendrites and fibre bundles. BCPI has been demonstrated to exhibit anti-parasitic activity and thus thought to act as a negative regulator of silk gland histolysis. Crammer has been identified in mushroom bodies (brain) of Drosophila melanogaster as one of the proteins essential for long-term memory formation through regulation of cathepsin activity in the insect. These findings suggest that the inhibitors are novel proteins that participate in various physiological actions in different organisms. Their emerging roles in normal biological tissues, diseases and as potential targets for drug development are discussed in detail

Dynamics and driving forces of hides, skins, leather and leather goods production and trade in Tanzania

Tanzania Veterinary Journal, 2014;29 (2): 1-17Hides, skins, leather and leather products are most traded commodities in the world and demand is increasing. Countries with large livestock populations have great opportunity to generate revenue from this resource. Studies were conducted in slaughterhouses, tanneries and leather good factories in Tanzania, aimed at determining quantities, qualities, processing and trade of hides and skins. Productions from slaughters are more than 3 million cattle hides, 3 million goatskins and 1 million sheepskins. Collected and exported quantities were 1,174,585 cattle hides, 1,591,990 and 304,167 goat and sheep skins. Companies from these destinations pre-pay livestock traders in advance and collect hides and skins at slaughter. Hides and skins are chrome or vegetable tanned at several industries including Afro Leather Industries Dar es Salaam while Himo Tanners and Planters and Afro Leather Industries produce finished leather. Qualities of hides were low because of flay cuts and brand markings. There is one leather footwear factory at Moshi and small scale leather goods factories in Arusha, Moshi, Mwanza, Dar es Salaam, Dodoma, Singida, Morogoro and in other places by individuals, youth groups, Vocational Education Training Authority (VETA) and Small Industries Organization (SIDO). Hides and skins processing is constrained by high international demand for raw hides and skins, inadequate investment in abattoirs, hides and skins collection and storage facilities and lack of trained personnel. Footwear and leather goods are constrained by lack of factories, competition from used goods, synthetic plastics and uninformed market. Investment in hides, skins and leather industry supported by training programmes has potential to generate great monetary revenue

A tsetse Glossina pallidipes harbors the pathogenic trypanosomes circulating in Liwale district, Tanzania

Veterinary Parasitology: Regional studies and reports 9 (2017) 93-97African Animal Trypanosomiasis (AAT) is among several constraints hindering development of the livestock sector in Tanzania. A survey was conducted in Liwale district located in southern Tanzania in 2013 to determine the population density of Glossina species, distribution pattern and Trypanosome species infection rate in tsetse flies. A total of 200 flies were collected from the study area and three Glossina species were identified. The proportional abundance of all trapped flies was 90% (180) for Glossina pallidipes, 6% (12) for G. brevipalpis and 4% (8) for G. m. morsitans with apparent densities (fly/trap/day - FTD) of 0.44. Higher density of Glossina pallidipes was observed in villages closer to than those far from the Selous game reserve. Trypanosomes were detected and identified by microscopy and ITS1 polymerase chain reaction (PCR) assay on DNA purified from 200 flies. Glossina pallidipes was the only fly found infected by three Trypanosoma species, namely T. vivax (60%), T. simiae (10%) and T. brucei (30%) with an overall infection rate of 10% (20/200). A higher proportion of trypanosome infections were observed in female tsetse flies than in males. Results of this study show that G pallidipes is the major Glossina species harboring pathogenic trypanosomes in Liwale district and that the Selous game reserve is a potential reservoir of trypanosomes in terms of parasite abundance and species diversity.COSTEC

Predicting body weight of Tanzania shorthorn zebu cattle using heart girth measurements

Livestock Research for Rural Development 23(4)Impact of research findings on Tanzania shorthorn zebu (TSHZ) cattle under agropastoral system in Tanzania have been lessened due to difficulties in relating visual appearance of animals with their live body weights. Managerial decisions have therefore been based on rough and inaccurate estimates. A simple, workable and accurate means was therefore thought to predict live weight of zebu cattle using heart girth measurement. A total of 300 TSHZ cattle were subjected to weighbridge as well as heart girth measurements and the findings subjected to regression analysis. Their live weights ranged from 170 to 390 Kg. The study revealed that heart girth had high correlation coefficient with live weight (r = 0.94, p<0.01). Grouping of data according to sex indicated that heart girth and live weight had closest correlation coefficient in both male and female, r = 0.9385 and r = 0.9318, respectively. The regression analysis of live weight on heart girth was highly significant (R² = 0.88, P<0.01), and the regression lines indicated that a linear relationship existed. The general equation for prediction of live weight of the TSHZ cattle was as follows: Y = 4.55 X – 409 (± 17.9), Where, Y = live weight (Kg), X = heart girth (cm). This implies that the use of the heart girth measurements in prediction of live weight of TSHZ cattle is credible