Osteoporotic hip and vertebral fractures in the Arab region: a systematic review.

Asia is projected to account for the largest proportion of the rising burden of osteoporotic fractures worldwide. Data from the Middle East is scarce. We performed a systematic review on the epidemiology of vertebral and hip osteoporotic fractures in 22 Arab League countries, using Scopus, PubMed, and Embase. We identified 67 relevant publications, 28 on hip and 39 on vertebral fractures. The mean age of patients was 70-74 years, female to male ratio 1.2:2.1. Age-standardized incidence rates, to the UN 2010 population, were 236 to 290/100,000 for women from Kuwait and Lebanon, lower in Morocco. Risk factors for hip fractures included lower BMD or BMI, taller stature, anxiolytics, and sleeping pills. Most patients were not tested nor treated. Mortality derived from retrospective studies ranged between 10 and 20% at 1 year, and between 25 and 30% at 2-3 years. Among 39 studies on vertebral fractures, 18 described prevalence of morphometric fractures. Excluding grade 1 fractures, 13.3-20.2% of women, mean age 58-74 years, had prevalent vertebral fractures, as did 10-14% of men, mean age 62-74 years. Risk factors included age, gender, smoking, multiparity, years since menopause, low BMD, bone markers, high sclerostin, low IgF1, hypovitaminosis D, abdominal aortic calcification score, and VDR polymorphisms. Vertebral fracture incidence in women from Saudi Arabia, mean age 61, was 6.2% at 5 years, including grade 1 fractures. Prospective population-based fracture registries, prevalence studies, predictive models, fracture outcomes, and fracture liaison services from Arab countries are still lacking today. They are the pillars to closing the care gap of this morbid disease.

Serum RANKL, osteoprotegerin (OPG) and RANKL/OPG ratio in children with systemic lupus erythematosus.

BACKGROUND: Systemic lupus erythematosus (SLE) patients have lower bone mineral density (BMD) compared with healthy individuals because of general, genetic, disease and medication-related factors. The disturbance of the receptor activator of nuclear factor-κB ligand (RANKL)/osteoprotegerin (OPG) ratio has been reported to be associated with low BMD in many disorders in adults and children alike. OBJECTIVES: The objectives of this study were (i) to assess serum OPG, RANKL and RANKL/OPG ratio levels in SLE children and controls, (ii) to determine whether the cumulative glucocorticoid (CGCS) dose had any effect on the concentration of serum RANKL, OPG and RANKL/OPG ratio, and (iii) to determine the relation of these parameters to BMD. METHODS: We evaluated 50 SLE children and 50 age- and sex-matched healthy controls. RANKL and OPG were assessed in serum and compared between patients and controls. For SLE patients, a univariate followed by multivariable analysis were carried out to detect the possible predictors of the changes in RANKL, OPG and RANKL/OPG ratio levels. Lumbar BMD for all patients was assessed by dual-energy X-ray absorptiometry (DXA) scan and then correlated to different probable correlated factors. RESULTS: RANKL, OPG and RANKL/OPG ratio were significantly higher in SLE patients (p ≤ 0.001). Univariate analysis showed significant correlations of RANKL with CGCS (p ≤ 0.001) and with DXA scan z-score (p = 0.007): OPG was significantly correlated to Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score (p = 0.001) and anti-double-stranded DNA (p = 0.001), whereas RANKL/OPG was significantly correlated to duration of illness and DXA z-score (p = 0.002). The multivariable analysis showed that DXA z-score was an independent predictor of RANKL and RANKL/OPG ratio (p = 0.019 and 0.008, respectively), whereas SLEDAI score was an independent predictor of OPG levels. BMD was negatively correlated to disease duration (p = 0.008) and CGCS dose (p = 0.015), but no significant correlation has been found between BMD and cumulative SLEDAI score (p = 0.29). CONCLUSIONS: Serum RANKL/OPG ratio is elevated in Egyptian children with SLE and is considered a risk factor for reduced bone mass in these children. Other risk factors for low BMD include high CGCS dose and disease duration, supporting that osteoporosis in SLE is multifactorial.

Interferon regulatory factor 5 gene polymorphism in Egyptian children with systemic lupus erythematosus.

Background Increased expression of interferon-inducible genes is implicated in the pathogenesis of systemic lupus erythematosus (SLE). Interferon regulatory factor 5 (IRF5) is one of the transcription factors regulating interferon and was proved to be implicated in the pathogenesis of SLE in different populations. Objectives The objective of this study was to investigate the correlation between polymorphisms of the IRF5 gene and SLE susceptibility in a cohort of Egyptian children and to investigate their association with clinico-pathological features, especially lupus nephritis. Subjects and methods Typing of interferon regulatory factor 5 rs10954213, rs2004640 and rs2280714 polymorphisms were done using polymerase chain reaction-restriction fragment length polymorphism for 100 children with SLE and 100 matched healthy controls. Results Children with SLE had more frequent T allele and TT genotype of rs2004640 ( Pc = 0.003 and 0.024, respectively) compared to controls. Patients with nephritis had more frequent T allele of rs2004640 compared to controls ( Pc = 0.003). However the allele and genotype frequencies of the three studied polymorphisms did not show any difference in patients with nephritis in comparison to those without nephritis. Haplotype GTA of rs10954213, rs2004640 and rs2280714, respectively, was more frequent in lupus patients in comparison to controls ( p = 0.01) while the haplotype GGG was more frequent in controls than lupus patients ( p = 0.011). Conclusion The rs2004640 T allele and TT genotype and GTA haplotype of rs rs10954213, rs2004640, and rs2280714, respectively, can be considered as risk factors for the development of SLE. The presence of the rs2004640 T allele increases the risk of nephritis development in Egyptian children with SLE.

Chemotherapy-induced differentiation to cure botryoid rhabdomyosarcoma: a case report and review of the literature.

Rhabdomyosarcoma (RMS) occurs rarely in adults and constitutes 2-6% of all uterine neoplasms. The authors report the case of a 26-year-old woman diagnosed with botryoid RMS that presented discordant progression results on follow up imaging and cytodifferentiation on pathologic control. This case showed that radiological evaluation could be misleading as the tumor demonstrated chemotherapy-induced differentiation without volume reduction. This case illustrates the limitations of using the imaging anatomical dimensions of sarcomas for treatment planning and highlights the potential role of functional imaging to assess the response to treatment.

The emergence of systemic lupus erythematosus in hypothyroid patients: two case reports and mini review.

Systemic lupus erythematosus (SLE) is a multi-systemic autoimmune disease that involves almost all the organs in the human body and is characterized by auto antibodies formation. Autoimmune thyroid diseases (AITD) are organ-specific diseases that are associated with a production of a variety of antibodies such as antinuclear antibodies, anti-double-stranded DNA, anti-Ro antibodies, anti-cardiolipin antibodies, and others. The diagnosis of AITD in patients with SLE is well known, but the reverse is rarely reported. We present two cases of adolescent girls in whom SLE evolved one year after being diagnosed with hypothyroidism.

Gravity profiles interpretation applying a metaheuristic particle optimization algorithm of mineralized bodies resembled by finite elements.

The interpretation of gravity anomalies is crucial for identifying subsurface mineralized targets and understanding the density variations between the targets and the surrounding structures. To confirm the presence of ore and mineral targets, simple geometric bodies are often used. One of the commonly used global metaheuristic algorithms for gravity data analysis is the particle optimization algorithm. In this study, we employed this method to determine the parameters of buried bodies that resemble finite vertical cylinders by inferring gravity anomalies profiles (amplitude coefficient, depth to top, depth to bottom, origin, and length of the target representing the difference between two depths). The algorithm utilizes particle movement to identify the best way to reach the global or optimum solution. The algorithm's performance was evaluated on synthetic-examples with and without noise (5 % and 10 % levels) and also verified on a real dataset for mineral exploration from Canada. The results showed that the algorithm's stability and accuracy were not affected by the presence of noise and multi-models. Moreover, the field case results were consistent with the existing geological information, borehole data, and previously published outcomes.

Cellular and molecular signatures of motherhood in the adult and ageing rat brain.

Pregnancy is marked by robust changes, including brain changes to volume, structure, connectivity and neuroplasticity. Although some brain changes are restricted to pregnancy and the postpartum, others are long-lasting. Few studies have examined possible mechanisms of these changes or the effects of multiple pregnancies. We characterized various cellular and molecular signatures of parity (nulliparous, primiparous, biparous) in the rat hippocampus. We investigated density of neural stems cells (Sox2), microglia (Iba-1) and levels of a synaptic protein (PSD-95), cell signalling pathways, neuroinflammation, and the tryptophan-kynurenine (TRP-KYN) pathway, one week after weaning their pups from the last pregnancy (age of dam: seven months) and in middle-age (age of dam: 13 months). Parity increased PSD-95 levels in both age groups and prevented the age-related decrease in neural stem cell density observed in nulliparous rats. Biparity increased cell signalling phosphoproteins (pp70S6K, S6RP) and number of microglia in the dentate gyrus, regardless of age. Parity resulted in transient changes to the TRP-KYN system. Thus, previous parity has lasting effects on synaptic plasticity with fewer lasting effects on inflammation and cell signalling phosphoproteins in the whole hippocampus.

Dentistry a second time?

INTRODUCTION: Dentistry in Jordan is an attractive profession due to the high social standard it provides. This study aimed to investigate whether dentists would choose dentistry again and whether their professional expectations would change after years of practice. Of special interest were possible differences according to gender, age, degree and place of work. METHODS: A self-completion questionnaire was filled by a stratified random sample of 355 dentists in Jordan using closed questions. The questionnaire included professional, social and economic factors that influenced people's choice of dentistry and whether they would choose it again and the reasons for that. RESULTS: The results showed that 52% of dentists who returned the questionnaire had dentistry as their first choice; the most important determining factor was the dentist's grades in the general secondary education. Fifty-two per cent stated that they would not choose it for the second time, the main reason being the health problems acquired through the profession and the low income. Helping others and the social standard dentistry provides were the main reasons given for dentists to choose dentistry again. CONCLUSION: We report that more than half of the dentists included in this study would not 'choose dentistry again' as their profession regardless of age, gender and degree. This is mainly due to health problems acquired and the low income. We found that job satisfaction is highly affected by the workplace, and that more females are dissatisfied by the profession. This suggests that cultural background strongly affects the career decision.

Preoperative Diagnosis Failure for a Rare Gastric Collision Tumor: A Case Report.

Gastrointestinal stromal tumors (GISTs) are common mesenchymal tumors of the gastrointestinal tract (GIT), usually occur as a solitary neoplasm. Inflammatory florid polyp (IFP) is a solitary rare benign lesion of the gastrointestinal tract, mainly occur in the gastric antrum, whose atypical presentation can mimic GISTs or other malignant tumors, therefore the synchronous occurrence of GISTs and IFP is extremely rare. We had a case of a 58-year-old man that was presented with recurrent epigastric pain and recurrent melena. Upper endoscopic examination revealed a large polypoid antrum polyp measured 7 cm at greatest dimension with focal ulceration. Clinical and radiological features did not reach the definite diagnosis until histopathological evaluation with immunohistochemical analysis was performed. Surgical intervention is recommended and partial gastrectomy was done with wide resection margins. Histological examination revealed two distinct GISTs and IFP parts presenting a collision tumor that showed spindle and epitheloid cells consistent with GISTs with histological features of florid polyp showed a characteristic perivascular onion-skin arrangement of spindle cells with dense chronic inflammatory infiltrate including eosinophils and lymphocytes. Immunohistochemical studies have been done and revealed an association between GISTs and IFP. To the best of our knowledge, this is the first case of a collision tumor consisting of a GIST and an IFP arising in the stomach. In conclusion, the gastrointestinal stromal tumor is the comments mesenchymal tumor of GIT and IFP is a rare benign lesion of GIT therefore association between GIST and IFP as a collision tumor is extremely rare.

Dentists' knowledge about medication-related osteonecrosis of the jaw and its management.

OBJECTIVES: To assess the knowledge of dentists regarding medication-related osteonecrosis of the jaw (MRONJ). METHODS: In this cross-sectional study, 74 dentists from governmental hospitals in Riyadh (Dental University Hospital in King Saud University, Military Hospital, National Guard Hospital), Jeddah (King Abdulaziz University Hospital, Ministry of Health Hospital), and the Eastern region of Saudi Arabia (Ministry of Health Hospitals in Dammam and Al-Ahsa) completed a two-part questionnaire. The first part gathered demographic data, such as sex and specialty. The second part included questions about bisphosphonate drugs and their indications; the identification of patients at risk of MRONJ; other medications associated with jaw necrosis; as well as the definition of MRONJ and its clinical features, risk factors, and preventive methods. RESULTS: Of the participating dentists, 60.8% knew about MRONJ, but only 35.1% were able to define it correctly. Most (79.7%) had never encountered MRONJ patients. Only 18.9% knew of the relationship between the risk of MRONJ in osteoporotic patients and long-term (>4 years) use of oral bisphosphonates or intravenous zoledronate, while 68.9% were unaware, and others answered incorrectly. Most participants did not know of MRONJ-predisposing medications, and 59.5% cited radiotherapy as the cause. Most participants identified dentoalveolar surgery as a major local factor, and the mandible as a common anatomic location. CONCLUSION: Dentists at the surveyed institutions had poor knowledge of MRONJ, although their knowledge of preventive measures was good. There is an urgent need for the optimization of educational programs pertaining to MRONJ, and its related dental management considerations. CLINICAL SIGNIFICANCE: Dentists in the surveyed institutions in Kingdom of Saudi Arabia have poor knowledge of MRONJ management; thus, greater effort should be taken to educate undergraduate and postgraduate students regarding this pathology.

Edaphic macrofauna in degradation of animal and vegetable residues.

The objective of this study was to evaluate the ability to degrade organic matter by edaphic macrofauna (worms), carbon/nitrogen (C/N) ratio and hydrogenation potential (pH) during the vermicomposting process in different organic residues. The treatments were constituted by organic residues of animal origin (bovine, ovine and equine manure) and vegetable (herb-checkmate and coffee drag), which were conditioned in plastic pots with a capacity of 10 liters, comprising five treatments in a completely randomized experimental design, with five replications. Were inoculated 150 earthworms of the species Eisenia foetida, into each plot. After 87 days, the evaluation of the multiplication of the earthworms was carried out, through its manual count and its cocoons. At the beginning and at the end of the experiment, the samples were submitted to analysis of humidity at 60 °C, pH, volumetric density, chemical analysis of macronutrients and C/N ratio. There was a dominance of worms and cocoons in the process of vermicomposting in the residues of ovine manure and herb-checkmate. The macronutrients (P, K and Mg) and C/N ratio were higher in the vegetal residues, while for N higher values were found in ovine manure and coffee drag treatments, and for Ca higher value among treatments was observed in the coffee drag treatment at the end and the lowest value at initiation. The results obtained in this study demonstrate the importance of the edaphic macrofauna to the vermicomposting process, since it allows more information about its influence on the continuity of soil organic matter decomposition processes.

Smooth muscle changes in varicose veins: an ultrastructural study.

In order to understand the pathology of varicose veins, we prospectively collected a total of 23 vein specimens both from the normal proximal thigh long saphenous vein (LSV) in 3 young trauma patients and from the unstripped proximal LSV near the sapheno-femoral junction and the distal calf blowouts in 10 primary varicose veins patients. Ultra-thin sections were examined under the transmission electron microscope (TEM). Compared with the normal control LSV, varicose vein sections showed increase in the diameter of the lumen, hypertrophy of the wall and elongation and invagination of the intima. Smooth muscle cells (SMCS) lost their normal fusiform shape and were widely separated by increased amounts of extra-cellular collagen fibers. The cells underwent marked degeneration, vacuolization and disintegration into fiber-like material and small separated fragments. SMCs were seen in the subintimal tissue and some of them were lost into tile lumen. SMCs also showed marked phagocytic activity, engulfing not only collagen and elastic fibers, but also other smooth muscle cells. Although these changes were more marked and advanced in the distal calf blowouts, they were also present in the proximal, clinically non-dilated LSV. In conclusion, SMCs of varicose veins show severe degeneration in both the distal calf blowouts and the proximal, clinically non-varicose LSV. It appears that they both form and phagocytose collagen and elastic fibers and play a major role in the pathogenesis of varicose veins.

Structural changes in the tunica intima of varicose veins: a histopathological and ultrastructural study.

Many factors have been implicated in the aetiology of varicose veins; however, there is ample evidence implicating that the defect is in the wall of the lower limb veins. In order to know the pathological changes in the tunica intima of varicose veins, the smooth muscle cells (SMCs), collagen and elastin of varicose and control patients were studied by light and electron microscopy. The morphological changes in the SMCs, collagen and elastin point to a possible secretory or phagocytic role of the SMCs in producing abnormal immature collagen or elastin fibres or in modulation of function of SMCs due to excessive production of extracellular matrix (ECM).

Changes of elastic and collagen fibers in varicose veins.

BACKGROUND: The resistance to stretch and the elasticity of the vein wall depend on the collagen and elastic fibers, respectively. Contradicting evidence exists, however, on the connective tissue concentration in varicose veins. METHODS: A prospective, comparative study was conducted at Asir Central Hospital and the College of Medicine in Abha, Saudi Arabia. Twenty-three vein specimens collected from both the proximal thigh long saphenous vein (LSV) and the distal calf blowouts in 10 primary varicose vein patients and from the normal, proximal thigh LSV in 3 young vascular trauma patients were examined. Paraffin sections stained with hematoxylin and eosin, Verhoeff von Gieson (VVG) and Masson's Trichrome stains were examined under the light microscope. Ultra thin sections were examined under the transmission electron microscope (TEM). RESULTS: Compared with the normal control LSV, varicose vein sections showed increased diameter of the lumen and hypertrophy of the wall, mainly of the intima, due to increased amounts of collagen fibers. This marked fibrous infiltration disrupted the normal palisade arrangement of the intimal and the regular sheet-like arrangement of the medial smooth muscle cells. Collagen fibers also lost their normal pattern and showed abnormal forms. Elastic fibers lost their regular laminar arrangement and formed clumps or scattered fragments. CONCLUSIONS: Varicose veins showed increased collagenosis and distortion of the elastic fibers. The presence of abnormal collagen to elastin ratio and the loss of the regular collagen/elastic lattice of the vein wall may play a major role in the pathogenesis of varicose veins.

Histopathological changes in the wall of varicose veins.

AIM: Vein wall distensibility is controlled by collagen, elastin and smooth muscle cells. However, contradicting evidence exists on the connective tissue concentration and smooth muscle pathology in varicose veins. METHODS: To study the pathological changes in the wall of varicose veins at different levels, we collected a total of 49 vein specimens from 19 patients at Asir Central Hospital, Abha, Saudi Arabia, during the period from March to October 1997. Three young trauma patients underwent repair of their arterial injuries using the thigh long saphenous vein (LSV) and 16 varicose vein patients underwent stripping of their LSV and avulsion of their distal calf varicosities. In the trauma patients, specimens were collected from the proximal thigh LSV while in the varicose vein patients, specimens were collected from both the groin and mid-thigh LSV and the distal calf varicosities. Specimens were stained with Hematoxylin & Eosin, Masson's Trichrome and von Gieson (VG) stains for examination under the light microscope. RESULTS: Compared with the normal LSV, all varicose vein sections showed marked intimal hypertrophy due fibrous tissue infiltration, localized thinning of the muscle layer and loss of both the intimal and medial smooth muscle cells (SMCs). Elastic fibers were deficient and scattered with loss of the normal elastin/collagen lattice network and decrease in both the muscle/collagen and elastin/collagen ratios. CONCLUSION: In conclusion, we propose that dilatation and distensibility of the vein wall under normal and increased venous pressure is due to deficiency in smooth muscle cells and elastic fibers and disproportionate increase in fibrous tissue.

Immunolocalization of an enterotoxic glycoprotein exoantigen on the secretory organelles of Cryptosporidium parvum sporozoites.

In this study, the fine ultrastructures of the secretory organelles of C. parvum sporozoites were demonstrated using transmission electron microscopy (TEM). Meanwhile, a previously identified enterotoxic 18-20 kDa copro-antigen (18-20 kDa CCA), associated with cryptosporidiosis in both human and calves, was isolated and immunolocalized on C. parvum sporozoites. Using immunoelectron microscopy and anti-18-20 kDa monospecific antibody demonstrated marked existence of the 18-20 kDa CCA on the apical organelles and at the trilaminar pellicles. An anterior extrusion-of this protein was demonstrated around the excysted and released sporozoites. However, non excysted sporozoites did not show this protein. Affinity blotting, with biotinylated jacalin, demonstrated the O-linked oligosaccharide moiety of this protein. The potential role of this protein in the host cell invasion and/or gliding motility remains unelucidated. However, its enterotoxicity, location and secretory nature suggest that it may be a target for neutralization or invasion inhibition of Cryptosporidium.

Intravascular detection of Giardia trophozoites in naturally infected mice. An electron microscopic study.

During routine transmission electron microscopic (TEM) examination of mice naturally infected with Giardia muris, an intense infection with Giardia trophozoites was demonstrated within intestinal and renal tissues. Examination of randomly taken sections from these heavily infected tissues revealed marked deep affection with mixed pathology. Duodenal sections were found loaded with Giardia trophozoites in intimate contact with necrotic gut cells. Some of these trophozoites were detected within central lacteal of damaged villi and nearby blood vessels. Interestingly, and for the first time to be demonstrated, morphologically identical G. muris trophozoite was detected in a renal blood vessel. An intense cellular immune reaction was obviously demonstrated with remarkable interaction between giant macrophages and the trophozoites particulates. Involvement of deep tissues by Giardia trophozoites and their presence within vascular channels could open up questions about the possible invasive and disseminative behavior of G. muris, particularly in heavily and naturally infected hosts.

Effect of dehydroepiandrosterone (DHEA) on memory and brain derived neurotrophic factor (BDNF) in a rat model of vascular dementia.

The effect of dehydroepiandrosterone (DHEA) on memory and cognition in experimental animals is well known, but its efficacy in clinical dementia is unproven. So, the aim of the present study was to investigate the effect of DHEA on learning and memory activities in a rat model of vascular dementia (VD). Forty-eight male rats that positively passed the holeboard memory test were chosen for the study before bilateral permanent occlusion of the common carotid artery. They were divided into four groups (n=12, each) as follows (i) untreated control, (ii) rats exposed to surgical permanent bilateral occlusion of the common carotid arteries (BCCAO) leading to chronic cerebral hypoperfusion, (iii) rats exposed to BCCAO then received DHEA (BCCAO + DHEA) and (i.v.) rats exposed to BCCAO then received donepezil (BCCAO + DON). Holeboard memory test was used to assess the time, latency, working memory and reference memory. Central level of acetylcholine, norepinephrine and dopamine in the hippocampus were measured. Furthermore, the expression of brain derived neurotrophic factor (BDNF) in the hippocampus was determined. Histopathological studies of the cerebral cortex and transmission electron microscope of the hippocampus were performed. BCCAO decreased the learning and memory activities in the holeboard memory. Also, it decreased the expression of BDNF as well as the central level of acetylcholine, noradrenaline and dopamine as compared to control rats. Treatment with DHEA and donepezil increased the working and reference memories, BDNF expression as well as the central acetylcholine in the hippocampus as compared to BCCAO rats. DHEA produced neuroprotective effects through increasing the expression of BDNF as well as increasing the central level of acetylcholine and catecholamines which are non-comparable to donepezil effects.

Edaphic macrofauna in degradation of animal and vegetable residues / Macrofauna edáfica no processo de vermicompostagem de resíduos animais e vegetais

Abstract The objective of this study was to evaluate the ability to degrade organic matter by edaphic macrofauna (worms), carbon/nitrogen (C/N) ratio and hydrogenation potential (pH) during the vermicomposting process in different organic residues. The treatments were constituted by organic residues of animal origin (bovine, ovine and equine manure) and vegetable (herb-checkmate and coffee drag), which were conditioned in plastic pots with a capacity of 10 liters, comprising five treatments in a completely randomized experimental design, with five replications. Were inoculated 150 earthworms of the species Eisenia foetida, into each plot. After 87 days, the evaluation of the multiplication of the earthworms was carried out, through its manual count and its cocoons. At the beginning and at the end of the experiment, the samples were submitted to analysis of humidity at 60 °C, pH, volumetric density, chemical analysis of macronutrients and C/N ratio. There was a dominance of worms and cocoons in the process of vermicomposting in the residues of ovine manure and herb-checkmate. The macronutrients (P, K and Mg) and C/N ratio were higher in the vegetal residues, while for N higher values were found in ovine manure and coffee drag treatments, and for Ca higher value among treatments was observed in the coffee drag treatment at the end and the lowest value at initiation. The results obtained in this study demonstrate the importance of the edaphic macrofauna to the vermicomposting process, since it allows more information about its influence on the continuity of soil organic matter decomposition processes.

Resumo Este estudo objetivou avaliar a capacidade de degradar a matéria orgânica pela macrofauna edáfica (minhocas), a relação carbono/nitrogênio (C/N) e o potencial hidrogeniônico (pH), durante o processo da vermicompostagem em diferentes resíduos orgânicos. Os tratamentos foram constituídos por resíduos orgânicos de origem animal (esterco bovino, ovino e equino) e vegetal (resíduo de erva-mate e borra-de-café), os quais foram acondicionados em vasos plásticos com capacidade de 10 litros, compondo cinco tratamentos em delineamento experimental inteiramente casualisado, com cinco repetições. Foram inoculadas 150 minhocas da espécie Eisenia foetida, em cada recipiente. Após 87 dias, foi realizada a avaliação da multiplicação das minhocas, através da sua contagem manual e seus casulos. Os resíduos foram submetidos, ao inicio e ao final do experimento, a análises de umidade a 60 °C, pH, densidade volumétrica, análise química de macronutrientes e relação C/N. Houve uma dominância de minhocas e casulos no processo da vermicompostagem nos resíduos de esterco ovino e erva-mate. Observou-se para os macronutrientes (P, K e Mg) e para a relação C/N uma maior quantidade nos resíduos vegetais, enquanto que para N valores maiores foram encontrados nos tratamentos esterco ovino e borra-de-café, e para Ca o maior valor entre os tratamentos foi observado no tratamento com borra de café ao final e o menor valor no inicio. Os resultados obtidos neste estudo demonstram a importância da macrofauna edáfica para o processo da vermicompostagem por possibilitar maiores informações sobre sua influência na continuidade dos processos de decomposição da matéria orgânica.