Study of the removal of dichlorvos and dimethoate in a titanium dioxide mediated photocatalytic process through the examination of intermediates and the reaction mechanism

The photocatalytic oxidation of two selected organophosphorous insecticides (dichlorvos and dimethoate) has been investigated. The aim of the study was the identification of the intermediates that are formed during photocatalytic treatment. Intermediate products from the slurry system were identified by means of solid-phase extraction (SPE) coupled to gas chromatography-mass spectroscopy techniques (GC-MS). Nine possible by-products were identified for dimethoate and three for dichlorvos. A proposed degradation pathway for each insecticide is presented, involving mainly oxidation and dealkylation reactions. The results demonstrated that some of the transient intermediates formed (oxon derivatives, disulfide, chlorinated fragments), were more toxic compared to parent compounds whereas most of them are less toxic than the parent compounds.     

Rapid cytomegalovirus pp65 antigenemia assay by direct erythrocyte lysis and immunofluorescence staining

A rapid cytomegalovirus (CMV) pp65 antigenemia assay with direct erythrocyte lysis (DL) with 0.8% NH4Cl, followed by indirect immunofluorescence staining (IF), was evaluated with 82 blood samples from renal transplant recipients, and the results were compared to those of the conventional antigenemia assay with dextran sedimentation and two-cycle alkaline phosphatase, anti-alkaline phosphatase staining (DS-APAAP). The DL-IF modification gave a higher leukocyte yield compared to DS-APAAP (75.4 versus 54.9%; P < 0.05), with similar leukocyte viability rates of >95%. The DL-IF methodology involved fewer technical steps, and the assay time was shortened from 5 h to less than 3 h. Nineteen of the 82 samples concordantly tested positive for pp65 antigenemia by both assays, and the readings showed a good correlation (r = 0.996; P < 0.01). No discordant results were observed. We conclude that the CMV pp65 antigenemia assay by this novel DL-IF modification is technically simpler, cheaper, and less time-consuming but yields results comparable to those of the conventional DS-APAAP assay. The shortened assay time and increased capacity to handle more samples confer distinct advantages in the rapid diagnosis and prompt treatment of CMV disease in immunosuppressed patients.     

Contraction of developing avian heart muscle

26 patients with at least one clinical symptom that could indicate a tear of the scapho-lunate interosseous ligament but normal static and dynamic radiographs were examined by arthroscopy. We found that a diagnosis of scapho-lunate instability could be established by dynamic manoeuvres during radio-carpal and mid-carpal arthroscopy. Five patients were found to have true scapholunate instability. Six tears of the interosseous ligament without instability were also detected but it was doubtful if the tear was the origin of the painful symptomatology. This experience suggests that dynamic manoeuvres during arthroscopy are superior to other methods in diagnosing scapholunate instabilities at the pre-radiographic stage.     

Anti-glomerular basement membrane and anti-neutrophil cytoplasm antibody-positive vasculitis presenting with peripheral neuropathy and acute renal failure

We report a case of Epstein-Barr (EB) infection that presented as an acute monoarthritis of the knee. This formed a Baker's cyst which ruptured into the gastrocnemius. The peripheral and synovial white blood counts were dominated by neutrophils. After repeated aspirations, spontaneous resolution occurred.     

Collagen induces cytokine release by fetal platelets: implications in scarless healing

In previous studies the authors demonstrated that unlike adult platelets, fetal platelets respond poorly to collagen. When platelets make contact with the exposed collagen at the site of injury, the result is activation, aggregation, and degranulation with the release of cytokines and growth factors. This sequence of events is well characterized in adult wounds, which heal with an acute inflammatory response and dense scar formation. In sharp contrast, fetal dermal wounds heal without an acute inflammatory response and minimal scar formation. Therefore, the aim of this study was to test the hypothesis that collagen, abundant at the site of dermal injury, is a poor inducer of cytokine release by fetal platelets. This could explain, in part, the minimal inflammation accompanying fetal dermal wound healing. Platelet suspensions from six fetal Yorkshire swine at day 80 of gestation (term, 114 days) were exposed to either arachidonic acid, 0.5 mg/mL, collagen, 0.19 mg/mL, or saline. The release into plasma of transforming growth factor-beta (TGF-beta 1), and platelet-derived growth factor (PDGF)-AB effected by these agents was determined by enzyme-linked immunosorbent assays. Transmission electron microscopy (TEM) was used to correlate the biochemical findings with ultrastructural changes and showed that arachidonate-treated platelets were aggregated and devoid of granules. In contrast, collagen-treated platelets had undergone conformational changes but showed only a moderate change in the quantity and homogeneity of their secretory granules compared with saline-treated controls. There was a significant increase in TGF-beta 1 release into plasma after treatment with collagen (6.64 +/- 0.36 ng/mL) and arachidonate (7.64 +/- 0.77 ng/mL) compared with saline (4.74 +/- 0.36 ng/mL), P < .05. Likewise, PDGF-AB release was significantly higher after collagen (0.22 +/- 0.02 ng/mL) and arachidonate treatment (0.44 +/- 0.04 ng/mL) compared with saline (0.09 +/- 0.02 ng/ mL), P < .05. The authors conclude that fetal platelets actually do release cytokines in response to contact with collagen despite poor aggregation. Therefore, impaired aggregation to collagen cannot solely explain the minimal inflammation after fetal wounding.     

Caesarean section in a pygmy hippopotamus (Choeropsis liberiensis) and the management of the wound

A laparohysterotomy was performed on a 17-year-old pygmy hippopotamus (Choeropsis liberiensis) to remove a dead over-sized fetus. The operation was successful and the animal recovered, but the surgical wound broke down and healed slowly by second intention.