Phosphorous Vacancy and Built-In Electric Field Effect of Co-Doped MoP@MXene Heterostructures to Tune Catalytic Activity for Efficient Overall Water Splitting.

Developing cost-effective, durable bifunctional electrocatalysts is crucial but remains challenging due to slow hydrogen/oxygen evolution reaction (HER/OER) kinetics in water electrolysis. Herein, a combined engineering strategy of phosphorous vacancy (Vp) and spontaneous built-in electric field (BIEF) is proposed to design novel highly-conductive Co-doped MoP@MXene heterostructures with phosphorous vacancy (Vp-Co-MoP@MXene). Wherein, Co doping regulates the surface electronic structure and charge re-distribution of MoP, Vp induces more defects and active sites, while BIEF accelerates the interfacial charge transfer rate between Vp-Co-MoP and MXene. Therefore, the synergistic integration of Vp-Co-MoP/MXene efficiently decreases activation energy and kinetic barrier, thus promoting its intrinsically catalytic activity and structural stability. Consequently, the Vp-Co-MoP@MXene catalyst displays low overpotentials of 102.3/196.5 and 265.0/320.0 mV at 10/50 mA cm-2 for HER and OER, respectively. Notably, two-electrode electrolyzers with the Vp-Co-MoP@MXene bifunctional catalysts to achieve 10/50 mA cm-2, only need low-cell voltages of 1.57/1.64 V in alkaline media. Besides, experimental and theoretical results confirm that the hetero-structure effectively reduces hydrogen adsorption free energy and rate-determining-step energy barrier of OER intermediates, thereby greatly boosting its intrinsically catalytic activity. This work verifies an effective strategy to fabricate efficient non-precious bifunctional electro-catalysts for water splitting via combination engineering of phosphorous vacancy, cation doping, and BIEF.

Investigating the Roles of Coat Protein and Triple Gene Block Proteins of Potato Mop-Top Virus Using a Heterologous Expression System.

Potato mop-top virus (PMTV) is an emerging viral pathogen that causes tuber necrosis in potatoes. PMTV is composed of three single-stranded RNA segments: RNA1 encodes RNA-dependent RNA polymerase, RNA2 contains the coat protein (CP), and RNA3 harbors a triple gene block (TGB 1, TGB2, and TGB3). CP plays a role in viral transmission, while TGB is known to facilitate cell-to-cell and long-distance systemic movement. The role of CP in symptom development, specifically in the presence of TGB genes, was investigated using potato virus X (PVX) as a delivery vehicle to express PMTV genes in the model plant Nicotiana benthamiana. Plants expressing individual genes showed mild symptoms that included leaf curling and crumpling. Interestingly, symptom severity varied among plants infected with three different combinations: CP with TGB1, CP with TGB2, and CP with TGB3. Notably, the combination of CP and TGB3 induced a hypersensitive response, accompanied by stunted growth and downward curling and crumpling. These results suggest the potential role of TGB co-expressed with CP in symptom development during PMTV infection. Additionally, this study demonstrates the use of the PVX-based expression system as a valuable platform for assessing the role of unknown genes in viral pathogenicity.

Novel 1-(1-Arylimiazolin-2-Yl)-3-Arylalkilurea Derivatives with Modulatory Activity on Opioid MOP Receptors.

µ-opioid receptor ligands such as morphine and fentanyl are the most known and potent painkillers. However, the severe side effects seen with their use significantly limit their widespread use. The continuous broadening of knowledge about the properties of the interactions of the MOP receptor (human mu opioid receptor, OP3) with ligands and specific intracellular signaling pathways allows for the designation of new directions of research with respect to compounds with analgesic effects in a mechanism different from classical ligands. Allosteric modulation is an extremely promising line of research. Compounds with modulator properties may provide a safer alternative to the currently used opioids. The aim of our research was to obtain a series of urea derivatives of 1-aryl-2-aminoimidazoline and to determine their activity, mechanism of biological action and selectivity toward the MOP receptor. The obtained compounds were subjected to functional tests (cAMP accumulation and ß-arrestin recruitment) in vitro. One of the obtained compounds, when administered alone, did not show any biological activity, while when co-administered with DAMGO, it inhibited ß-arrestin recruitment. These results indicate that this compound is a negative allosteric modulator (NAM) of the human MOP receptor.

Liuwei Dihuang pills attenuate ovariectomy-induced bone loss by alleviating bone marrow mesenchymal stem cell (BMSC) senescence via the Yes-associated protein (YAP)-autophagy axis.

CONTEXT: Liuwei Dihuang pill (LWDH) has been used to treat postmenopausal osteoporosis (PMOP). OBJECTIVE: To explore the effects and mechanisms of action of LWDH in PMOP. MATERIALS AND METHODS: Forty-eight female Sprague-Dawley rats were divided into four groups: sham-operated (SHAM), ovariectomized (OVX), LWDH high dose (LWDH-H, 1.6 g/kg/d) and LWDH low dose (LWDH-L, 0.8 g/kg/d); the doses were administered after ovariectomy via gavage for eight weeks. After eight weeks, the bone microarchitecture was evaluated. The effect of LWDH on the differentiation of bone marrow mesenchymal stem cells (BMSCs) was assessed via osteogenesis- and lipogenesis-induced BMSC differentiation. The senescence-related biological indices were also detected using senescence staining, cell cycle analysis, quantitative real-time polymerase chain reaction and western blotting. Finally, the expression levels of autophagy-related proteins and Yes-associated protein (YAP) were evaluated. RESULTS: LWDH-L and LWDH-H significantly modified OVX-induced bone loss. LWDH promoted osteogenesis and inhibited adipogenesis in OVX-BMSCs. Additionally, LWDH decreased the positive ratio of senescence OVX-BMSCs and improved cell viability, cell cycle, and the mRNA and protein levels of p53 and p21. LWDH upregulated the expression of autophagy-related proteins, LC3, Beclin1 and YAP, in OVX-BMSCs and downregulated the expression of p62. DISCUSSION AND CONCLUSIONS: LWDH improves osteoporosis by delaying the BMSC senescence through the YAP-autophagy axis.

The Novel MFG-E8-derived Oligopeptide, MOP3, Improves Outcomes in a Preclinical Murine Model of Neonatal Sepsis.

INTRODUCTION: Neonatal sepsis is a devastating inflammatory condition that remains a leading cause of morbidity and mortality. Milk fat globule-EGF-factor VIII (MFG-E8) is a glycoprotein that reduces inflammation, whereas extracellular cold-inducible RNA binding protein (eCIRP) worsens inflammation. This study aimed to determine the therapeutic potential of a novel MFG-E8-derived oligopeptide 3 (MOP3) designed to clear eCIRP and protect against inflammation, organ injury, and mortality in neonatal sepsis. METHODS: C57BL6 mouse pups were injected intraperitoneally with cecal slurry (CS) and treated with MOP3 (20 µg/g) or vehicle. 10 h after injection, blood, lungs, and intestines were collected for analyses, and in a 7-day experiment, pups were monitored for differences in mortality. RESULTS: MOP3 treatment protected septic pups from inflammation by reducing eCIRP, IL-6, TNFα, and LDH. MOP3 reduced lung and intestinal inflammation and injury as assessed by reductions in tissue mRNA levels of inflammatory markers, histopathologic injury, and apoptosis in lung and intestines. MOP3 also significantly improved 7-day overall survival for CS-septic mouse pups compared to vehicle (75% vs. 46%, respectively). CONCLUSION: Deriving from MFG-E8 and designed to clear eCIRP, MOP3 protects against sepsis-induced inflammation, organ injury, and mortality in a preclinical model of neonatal sepsis, implicating it as an exciting potential new therapeutic. LEVEL OF EVIDENCE: Level 1.

Cebranopadol, a novel long-acting opioid agonist with low abuse liability, to treat opioid use disorder: Preclinical evidence of efficacy.

Maintenance therapy with buprenorphine and methadone is the gold standard pharmacological treatment for opioid use disorder (OUD). Despite these compounds demonstrating substantial efficacy, a significant number of patients do not show optimal therapeutic responses. The abuse liability of these medications is also a concern. Here we used rats to explore the therapeutic potential of the new long-acting pan-opioid agonist Cebranopadol in OUD. We tested the effect of cebranopadol on heroin self-administration and yohimbine-induced reinstatement of heroin seeking. In addition, we evaluated the abuse liability potential of cebranopadol in comparison to that of heroin under fixed ratio 1 (FR1) and progressive ratio (PR) operant self-administration contingencies. Oral administration of cebranopadol (0, 25, 50 µg/kg) significantly attenuated drug self-administration independent of heroin dose (1, 7, 20, 60µg/inf). Cebranopadol also reduced the break point for heroin (20 µg/inf). Finally, pretreatment with cebranopadol significantly attenuated yohimbine-induced reinstatement of drug seeking. In abuse liability experiments under FR1 contingency, rats maintained responding for heroin (1, 7, 20, 60µg/inf) to a larger extent than cebranopadol (0.03, 0.1, 0.3, 1.0, 6.0µg/inf). Under PR contingency, heroin maintained responding at high levels at all except the lowest dose, while the break point (BP) for cebranopadol did not differ from that of saline. Together, these data indicate that cebranopadol is highly efficacious in attenuating opioid self-administration and stress-induced reinstatement, while having limited abuse liability properties. Overall, the data suggest clinical potential of this compound for OUD treatment.

MoP quantum dots based multifunctional efficient electrocatalyst for stable and long-life flexible lithium-sulfur batteries.

The commercialization of lithium-sulfur (Li-S) batteries is challenging, owing to factors like the poor conductivity of S, the 'shuttle effect', and the slow reaction kinetics. To address these challenges, MoP quantum dots were decorated on hollow carbon spheres (MoPQDs/C) in this study and used as an efficient lithium polysulfides (LiPSs) adsorbents and catalysts. In this approach polysulfides are effectively trapped through strong chemisorption and physical adsorption while simultaneously facilitating LiPSs conversion by enhancing the reaction kinetics. MXene serves as a flexible physical barrier (MoPQDs/C@MXene), further enhancing the confinement of LiPSs. Moreover, both materials are conductive, significantly facilitating electron and charge transfer. Additionally, the flexible MoPQDs/C@MXene-S electrode offers a large specific surface area for sulfur loading and withstand volume expansion during electrochemical processes. As a result, the MoPQDs/C@MXene-S electrode exhibits excellent long-term cyclability and maintains a robust specific capacity of 992 mA h g-1 even after 800cycles at a rate of 1.0C (1C = 1675 mA g-1), with a minimal capacity decay rate of 0.034 % per cycle. This work proposes an efficient strategy to fabricate highly efficient electrocatalysts for advanced Li-S batteries.

Production of Double-Stranded RNA in Planta by a Potato Mop-Top Virus (PMTV)-Based Vector for Inducing Gene Silencing.

RNA silencing (also known as gene silencing) is an evolutionary conserved mechanism that is involved in regulating gene expression, suppressing mobile elements, and defensing virus infection. RNA silencing is triggered by double-stranded RNA via Dicer or Dicer-like riboendonucleases. DsRNAs are also the replication intermediates of all RNA viruses; as a result, plant RNA viruses are ideal candidates to induce RNA silencing. A large body of plant viruses have been modified into vectors for RNA silencing in varied plant species. Here, we described a simple, time-saving, and operable system for gene function and genetic breeding study of potato and Nicotiana benthamiana using a potato mop-top (MPTV)-based vector.

Mistakes of Surgeons: “Gossypiboma” Sometimes Brings Grave Consequence to the Patient

Retained surgical mop in the abdominal cavity is a serious butavoidable complication which may manifest either as aninflammatory reaction with formation of abscess and fistula orwith a fibrotic reaction developing into a mass. We report thecase of a 25 years old women who presented four monthsafter a Caesarean section with features of intestinalobstruction. Plain abdominal radiograph and ultrasound scanraised high index of suspicion of the presence of gossypibomaand the diagnosis was confirmed at laparotomy. Even after 2ndand 3rd look surgery, the patient faced a sad demise.Gossypiboma, term derived from the latin ‘gossypium’ (cotton)and the swahilli ‘boma’ (place of concealment) is the term formretained surgical sponge. Two usual responses to retainedmops are exudative inflammatory reaction to develop a mass.Intraluminal migration is rare, leading to obstruction. Patientmay develop symptoms of abdominal pain, nausea, vomitingand weight loss resulting from obstruction or a malabsorptionsyndrome caused by multiple intestinal fistulas or intraluminalbacterial overgrowth. Early recognition of this entity will ensureprompt diagnosis and appropriate treatment, reducingmorbidity and mortality in such patients.

Role of Tc-99m MDP Bone Scintigraphy in the evaluation of suspected Chondrosarcoma from OIiier Disease: A rare case repor

@# OIiier disease is a rare nonhereditary disorder characterized by multiple enchondromas in which malignant changes may occur. We report the case of a 15-year-old male with Ollier disease who presented with a large mass in the left upper arm for several months. Radiography revealed hugelytic mass in the proximal half to two-thrids of the left humerus. Bone scan showed irregularly increased tracer uptake in the head to mid shaft of the left humerus that is suggestive of malignant disease. Pathology analysis demonstrated proximal humeral chondrosarcoma, grade 1. In Ollier disease, bone scan may be used for monitoring the lessions with suspicion for malignant transpormation.

Establishment of Mus Skin Photo-damage Model by 8-MOP plus UVA Irradiation / 华中科技大学学报（医学）（英德文版）

To establish a simple and reliable animal model of skin photo-damage, 20 mice were treated with 8-MOP and exposed to UVA (UVA 320-400 nm) for 24 h. After irradiation, the structure of the epidermis and dermis, collagen fibers, elastic fibers were observed by using HE staining and Weigert technique and compared with the normal controls. The acanthosis and epidemis proliferation with accompanying hyperkeratosis and parakeratosis were observed. Inflammatory infiltration was noted in the dermis. The elastic fibers became coarse, irregularly arranged and clustered, with their number increased. The collagen fibers showed obvious degeneration and some amorphous materials could also be observed. The blood vessels were irregularly dilated and vascular walls were thickened, with infiltration of inflammatory cells. It is concluded that murine photodamage model can be quickly, conveniently and reliably established by means of 8-MOP/UVA.

Niveles plasmáticos de mieloperoxidasa y proteína C reactiva en conejos machos en Nueva Zelanda expuestos a una dieta hiperlipidémica / Plasma concentration of myeloperoxidase and C reactive protein in male New Zealand rabbits, exposed to a hyperlipidemic diet

La Mieloperoxidasa (MPO) y la Proteína C Reactiva (PCR) han sido implicados en la fisiopatología de la aterosclerosis. El objetivo del presente estudio fue determinar las concentraciones plasmáticas de MPO y PCR y su relación con la formación de ateromas en conejos. Se estudiaron 23 conejos machos Nueva Zelanda: Grupo 1: conejarina y verdura; Grupo 2: Huevo y conejarina. El periodo experimental duró 13 semanas. Se determinó perfil lipídico por métodos enzimáticos, MPO por ELISA y PCR por turbidimetría en 0 13va semana. Se realizó estudio histológico de aorta. Los resultados revelaron que la PCR se elevó en el grupo 2 al final del estudio (p<0,05). No se observó diferencias en MPO en el grupo 2 en el estudio. En cuanto a los ateromas se evidenciaron lesiones tipo I y II en los conejos del grupo 2. En conclusión, se encontró que la PCR y no la MPO son marcadores de aterosclerosis según nuestras condiciones experimentales.

Myeloperoxidase (MPO) and C-reactive protein (CRP) have been implicated in atherosclerosis. The objective of the present study was to determine plasma concentration MPO and CRP and its relationship of formation of aortic lesions in rabbits. 23 male New Zealand rabbits were study: Group 1: “conejarina” (commercial rabbit food) and vegetables; Group 2: egg and conejarina. The experiment lasted 13 weeks. Lipid profile was done by enzymatic methods, MPO by ELISA, and PCR by turbidimetry in weeks 0 and 13. Histological study of rabbits’ aorta was done. Results revealed that in group 2 CRP increased at final study (p <0.05). No differences were observed in MPO values in the experiment. Regarding atheroma, group 2 presented type I and II lesions. In conclusion only CRP is marker of atherosclerosis according to our experimental conditions.

Effect of nitrogen availability on the oxygen consumption during mineralization of Scirpus cubensis from Infernão Lagoon (São Paulo-Brazil) - DOI: 10.4025/actascibiolsci.v29i2.524 / Efeito da disponibilidade de nitrogênio no consumo de oxigênio durante a mineralização de Scirpus cubensis da Lagoa do Infernão (São Paulo, Brasil) - DOI: 10.4025/actascibiolsci.v29i2.524

This study evaluated the influence of nitrogen additions in the oxygen uptake during decomposition of Scirpus cubensis, through laboratory assays. The dissolved oxygen, pH, electrical conductivity (EC) and water temperature were measured. The results showed an initial acidification that decreased gradually, indicating great release of reduced organic matter and subsequent CO2 formation. The decomposition chambers with greater nitrate concentrations exhibited higher pH mean values. The temporal variation of EC showed a small increase and an abrupt increase with increasing nitrate concentrations. The maximum oxygen uptake increased up to 6.37 mg L-1 of nitrate, then decreased. The deoxygenation rate showed an opposite trend from that observed for the oxygen uptake. The coefficients and maximum oxygen consumption related to the particulate detritus mineralization tended to increase with increasing nitrate concentration. The increase in nitrate levels affected the decomposition of each organic matter fraction in different ways, with the particulate organic matter being more easily degraded in richer nitrate concentrations than the dissolved organic matter.

Neste estudo, avaliou-se a influência de adições de nitrogênio no consumo de oxigênio durante a decomposição de Scirpus cubensis, por meio de ensaios de laboratório. Foram determinados: as concentrações de oxigênio dissolvido, o pH, a condutividade elétrica e a temperatura da água. Os resultados mostraram acidificação inicial que diminuíram gradualmente, indicando grande liberação de matéria orgânica reduzida e formação subseqüente de CO2. As câmaras de decomposição com maiores concentrações de nitrato apresentaram valores de pH mais alto. A condutividade elétrica mostrou pequeno incremento com o passar do tempo e aumento abrupto com a intensificação das concentrações de nitrato. O consumo de oxigênio máximo global aumentou até a concentração de nitrato de 6,37 mg L-1, depois decresceu. Os coeficientes globais de consumo de oxigênio apresentaram uma tendência oposta às quantidades máximas de oxigênio consumido. Os coeficientes de consumo de oxigênio, relacionados com a mineralização das frações particuladas, tenderam a aumentar com a elevação da concentração de nitrato. O aumento do nível de nitrato afetou diferentemente a decomposição das frações da matéria orgânica; a matéria orgânica particulada foi mais facilmente degradada do que a dissolvida em presença de maiores concentrações de nitrato.

Study of the skin concentrations after administration of the various phototoxic drugs

The skin concentrations of 8-methoxypsoralen (8-MOP), 5-methoxypsoralen (5-MOP), and 4, 5', 8-trimethylpsoralen (TMP) were studied in the guinea pig following oral administration and bathing. The skin concentration of phototoxic drugs after oral administration peaked at 1.5 hours, and the concentration of 8-MOP was 3.5 times greater than that of 5-MOP. The skin concentration of TMP was not detected in our study (limit of sensitivity 5ng/ml). The skin concentrations of phototoxic drug after bathing decreased in the order of 5-MOP, TMP, and 8-MOP

Studies on the Effects of Various Topical Phototoxic Drugs and UVA on Melanocytes of C57 BL Mice

One hundred sixteen C57 BL mice were painted with either 8-MOP, 5-MOP or TMP solution in concentrations of 0.02%, 0.1%, and 0.5% each and UVA irradiated. Skin biopsies were performed at 1, 3, 5 and 7 weeks after LJVA irradiation. The results measuring the number, area, and perimeter of the melanocytes after topical PLJVA were higher in the TMP-painted group than in the 8-MOP or 5-MOP painted groups. In all groups, the weekly changes showed an increasing value through five weeks. In comparing the drug concentrations used, 0.1% of chemicals produced the same or higher values than 0.5%. There have been few studies on the effects of 5-MOP in photochemotherapy. In tho study 5-MOP produced a pigment-producing effect similar to 8-MOP. Therefore, if topical PIJVA with 5-MOP is used in clinical practice, we could expect a significant therapeutic effect in vitiligo.

Treatment of Witiligo with Oral Methoxsalen and UVA / 대한피부과학회지

Among ]20 vitiligo patients who visited our clinic during the period of January 1984 to February 1985, 39 patients were treated with oral methoxsalen (8-MOP) and UVA for more than 6 months, The following conclusions were obtained by analysis of the clinical histories and efficacy of PUVA treatment: 1. The mean age of 39 patients was 31 and that of onset was 21. An average of 1() years elapsed from the onset of the disease prior to visiting our clinic. The initial involvement was observed, in decreasing order of frequency, on the trunk, face and/or neck and extremities. 3, The repigmentation started most frequently from the trunk followed by the extremities, face and/or neck after treatment of 2 months and 14 irradiations on the average. 4, There was a direct relationship between the frequency and duration of treatment and its effectiveness. 5. The trunk showed the best response to the treatment, followed by the extremities; face and/or neck. The most resistant sites were the the hand and/or foot. 6. No specific relationship was found between the patient's age, duration of illness and responsiveness to the treatment. 7. The side effects were minimal and transient.

Effects of 8 - Methoxypsoralen ( 8 - MOP ) on the Proliferation and Melanization of Cultured Normal Human Melanocytes without UVA / 대한피부과학회지

BACKGROUND: Psoralen has been used in the treatment of certain hypojigmentary disorders with UVA or solar irradiation. However trecent report proposed the actions of psiralens are direct and do not require the presence of ultraviolet light. The report also suggested that tze specific receptors other than DNA would be present. OBJECTIVE: This study was done ta identify the effects of 8-methoryporalen(8-MOP) on the proliferation and melanization of cultured normal human melanocytes without UVA. METHODS: Melanocytes were cultured in melanocyte culture medium neluding 16% or 5% FBS. We added 8-MOP by their concentrations from 10 M to 10 M. After 8 hours treatment, we investigated the melanocytes proliferation and Lhe melanin contents. RESULTS: We could not detecet any significant differences of melanoytes proliferation and melanin contents between the control end experimental groups. CONCLUSION: There were no effect on the proliferation and the milanization of cultured normal human melanocytes with 8-MOP only.

Study of the Therapeutic Effect of8-methoxypsoralen Liposome Gel on Leukodermia in Guinea-pig Models / 中国药房

OBJECTIVE:To compare the therapeutic effects of8-methoxypsoralen(8-MOP)liposomal gel with other dosage forms of8-MOP in equal concentration on guinea-pig models of vitiligo.METHODS:The guinea-pigs were divided into normal control,model,8-MOP tincture,8-MOP gel and8-MOP liposome gel groups.The vitiligo model was established by chemical decoloration method in all groups except normal control group,then corresponding preparations were topically ap?plied.The therapeutic effects were compared and the melanogenesis of hair follicles,serum acetylcholinesterases and skin MDA contents were observed in all groups.RESULTS:8-MOP liposomal gel had better therapeutic effects on the animal models,and could improve the dermatic melanogenesis and acetylcholinesterase of the animal model,and also had effect on MDA of skin.The differences between8-MOP liposomal gel group and model group were highly significant(P

Effect of nitrogen availability on the oxygen consumption during mineralization of Scirpus cubensis from Infernão Lagoon (São Paulo-Brazil) - DOI: 10.4025/actascibiolsci.v29i2.524 / Efeito da disponibilidade de nitrogênio no consumo de oxigênio durante a mineralização de Scirpus cubensis da Lagoa do Infernão (São Paulo, Brasil) - DOI: 10.4025/actascibiolsci.v29i2.524

This study evaluated the influence of nitrogen additions in the oxygen uptake during decomposition of Scirpus cubensis, through laboratory assays. The dissolved oxygen, pH, electrical conductivity (EC) and water temperature were measured. The results showed an initial acidification that decreased gradually, indicating great release of reduced organic matter and subsequent CO2 formation. The decomposition chambers with greater nitrate concentrations exhibited higher pH mean values. The temporal variation of EC showed a small increase and an abrupt increase with increasing nitrate concentrations. The maximum oxygen uptake increased up to 6.37 mg L-1 of nitrate, then decreased. The deoxygenation rate showed an opposite trend from that observed for the oxygen uptake. The coefficients and maximum oxygen consumption related to the particulate detritus mineralization tended to increase with increasing nitrate concentration. The increase in nitrate levels affected the decomposition of each organic matter fraction in different ways, with the particulate organic matter being more easily degraded in richer nitrate concentrations than the dissolved organic matter.

Neste estudo, avaliou-se a influência de adições de nitrogênio no consumo de oxigênio durante a decomposição de Scirpus cubensis, por meio de ensaios de laboratório. Foram determinados: as concentrações de oxigênio dissolvido, o pH, a condutividade elétrica e a temperatura da água. Os resultados mostraram acidificação inicial que diminuíram gradualmente, indicando grande liberação de matéria orgânica reduzida e formação subseqüente de CO2. As câmaras de decomposição com maiores concentrações de nitrato apresentaram valores de pH mais alto. A condutividade elétrica mostrou pequeno incremento com o passar do tempo e aumento abrupto com a intensificação das concentrações de nitrato. O consumo de oxigênio máximo global aumentou até a concentração de nitrato de 6,37 mg L-1, depois decresceu. Os coeficientes globais de consumo de oxigênio apresentaram uma tendência oposta às quantidades máximas de oxigênio consumido. Os coeficientes de consumo de oxigênio, relacionados com a mineralização das frações particuladas, tenderam a aumentar com a elevação da concentração de nitrato. O aumento do nível de nitrato afetou diferentemente a decomposição das frações da matéria orgânica; a matéria orgânica particulada foi mais facilmente degradada do que a dissolvida em presença de maiores concentrações de nitrato.