Electrochemical determination of paraquat in citric fruit based on electrodeposition of silver particles onto carbon paste electrode

Carbon paste electrodes (CPEs) modified with silver particles present an interesting tool in the determination of paraquat (PQ) using square wave voltammetry. Metallic silver particle deposits have been obtained via electrochemical deposition in acidic media using cyclic voltammetry. Scanning electron microscopy and X-ray diffraction measurements show that the silver particles are deposited onto carbon surfaces in aggregate form. The response of PQ with modified electrode (Ag-CPE) related to Ag/CP loading, preconcentration time, and measuring solution pH was investigated. The result shows that the increase in the two cathodic peak currents (Peak 1 and Peak 2), under optimized conditions, was linear with the increase in PQ concentration in the range 1.0 × 10⁻⁷ mol/L to 1.0 × 10⁻³ mol/L. The detection limit and quantification limit were 2.01 × 10⁻⁸ mol/L and 6.073 × 10⁻⁸ mol/L, respectively for Peak 1. The precision expressed as relative standard deviation for the concentration level 1.0 × 10⁻⁵ mol/L (n = 8) was found to be 1.45%. The methodology was satisfactorily applied for the determination of PQ in citric fruit cultures.     

Kidney Transplantation: Charles Nicolle Hospital Experience

The aim of our retrospective study was to analyze the short- and long-term follow-up of 298 renal transplantations performed between June 1986 and May 2005. All were first transplantations except 4 cases, with 54 from cadaveric and 244 from living donors. The recipients included 196 males and 102 females of overall mean age of 31.21 ± 8.9 years (range, 16-61 years). A combination of prednisolone and azathioprine was presented for 212 patients or mycophenolate mofetil for 86 patients. Polyclonal or monoclonal antibodies were used as induction therapy in 183 cases. Cyclosporine was administered to 188 cases and tacrolimus only to 16.HLA matching was 0 mismatches (MM) in 65 cases; 1 or 2 MM in 113; 3 MM in 99; and ≥4 MM in 21. Acute tubular necrosis occurred in 45 cases. One hundred eighteen patients experienced at least 1 acute rejection episode: 102 cases (41.8%) among living and 16 (29.6%) among cadaveric kidneys donor (P = .0007). The actuarial patient and graft survival rates at 1, 5, 10, 15, and 20 years were 95.9%, 87.4%, 77.5%, 65.6%, and 60.8%, and 94.9%, 84.5%, 75.4%, 65.4%, and 53%, respectively. Sixty-three patients died and 72 patients returned to dialysis. Our results were comparable to experienced centers. However, the member of kidney transplantations does not match the increased number of patients on renal replacement therapy. It is advisable to promote obtaining organs from brain-dead donors.     

Radio-chemotherapy in head and neck cancer (EGFR+)

Squamous-cell carcinoma of the head and neck are neoplasic diseases for which locoregional control remains very important, given its particular pattern of failure. Treatment of early stage disease involves surgery or radiation therapy. Locally advanced disease is treated either with concurrent chemoradiotherapy or surgery followed by radio-chemotherapy, according to each center's expertise. Recent research has demonstrated that the overexpression of epidermal growth factor receptor (EGFR) is associated with tumor progression. Based on this research, a new type of anticancer therapy, so-called "targeted therapies" represent important additions to the current therapeutic arsenal in the management of head and neck cancers, based on results of a phase III trial combining radiotherapy and immunotherapy with cetuximab.     

Prevalence of hospital-acquired infection in a Moroccan university hospital

BACKGROUND: Infection control and hospital-acquired infection (HAI) prevalence reports from developing countries are often not well established because of the lack of staff and resources. The aim of this study was to estimate the prevalence of HAI in a Moroccan hospital as well as to identify its predisposing factors. METHODS: A one-day prevalence survey was conducted in April 2005 at Ibn Sina University Hospital which included all inpatients who had been in the hospital for at least 48 hours. RESULTS: Among 658 patients surveyed, the prevalence of HAI was 17.8%. The prevalence was higher in intensive care units (50%). The most frequently infected sites were urinary tract (35%) and surgical wounds (32.5%). Microbiological documentation was available in only 31.6% of HAIs. The most frequently isolated organisms were Staphylococcus aureus (30%) and Proteus mirabilis (25%). Results of multiple logistic regression analysis indicated that HAI is linked to the surgical category, a hospital stay of more than 10 days, and the use of intravascular and urinary devices. CONCLUSIONS: The prevalence of HAI is high at our center. This survey provided the principal information for future surveillance and prevention programs in Morocco.     

Feasibility and efficacy of subcutaneous amifostine therapy in patients with head and neck cancer treated with curative accelerated concomitant-boost radiation therapy

OBJECTIVE: To assess the feasibility and efficacy of subcutaneous amifostine therapy in patients with head and neck cancer treated with curative accelerated radiotherapy (RT). DESIGN: Retrospective study. SETTING: University of Lausanne, Lausanne, Switzerland. PATIENTS: Thirty-three consecutive patients (male-female ratio, 4.5; median age, 54 years [age range, 39-76 years]). INTERVENTIONS: Between November 2000 and January 2003, the 33 patients were treated with curative definitive (n = 19) or postoperative (n = 14) RT with (n = 26) or without (n = 7) chemotherapy. All patients received conformal RT. Fractionation schedule consisted of concomitant-boost (Friday afternoon session) accelerated RT using 70 Gy (2 Gy per fraction) in 6 weeks in patients treated with definitive RT and 66 Gy (2 Gy per fraction) in 5 weeks and 3 days in the postoperative setting. Parotid glands received at least 50 Gy in all patients. Amifostine was administered to a total dose of 500 mg subcutaneously, 15 to 30 minutes before morning RT sessions. RESULTS: All patients received their planned treatment (including chemotherapy). Ten patients received the full schedule of amifostine (at least 25 injections), 9 received 20 to 24 doses, 4 received 10 to 19 doses, 5 received 5 to 9 doses, and 5 received fewer than 5 doses. Fifteen patients (45%) did not show any intolerance related to amifostine use. Amifostine therapy was discontinued because of nausea in 11 patients (33%) and hypotension in 6 patients (18%), and 1 patient refused treatment. No grade 3, amifostine-related, cutaneous toxic effects were observed. Radiotherapy-induced grade 3 acute toxic effects included mucositis in 14 patients (42%), erythema in 14 patients (42%), and dysphagia in 13 patients (39%). Late toxic effects included grade 2 or more xerostomia in 17 patients (51%) and fibrosis in 3 patients (9%). Grade 2 or more xerostomia was observed in 8 (42%) of 19 patients receiving 20 injections or more vs 9 (64%) of 14 patients receiving fewer than 20 injections (P = .15). CONCLUSIONS: Subcutaneous amifostine administration in combination with accelerated concomitant-boost RT with or without chemotherapy is feasible. The major adverse effect of subcutaneous administration was nausea despite prophylactic antiemetic medication, and hypotension was observed in only 6 patients (18%).     

Clinical evaluation of lipids,lipoproteins and red blood cells sodium and potassium in patients with different grades of hypertension

ObjectivesTo show that lipid and lipoprotein levels and cell sodium and potassium content and transport could change depending on the degree of hypertension.Design and methodsForty-three hypertensive patients and 20 healthy subjects were recruited at the Cardiology and Biochemistry Departments of Tlemcen University Hospital Centre (Northwest of Algeria).ResultsLevels of CHOL, TG, PL, HDL-TG, LDLc, LDL-TG, LDL-PL, HDL2-TG and HDL3-TG were significantly higher in hypertensive patients than those in controls. HDL-PL levels were significantly lower in patients compared with controls and decreased according to the grade of hypertension. HDL2c, HDL2-PL and HDL3-TG and cell content and fluxes of sodium and potassium change gradually with higher grades of hypertension.ConclusionsHypertensive patients with circulating lipid alterations are associated to ion cell content and transport abnormalities, which were worsened progressively with higher grade of hypertension.     

How we approach conservative treatment of retinoblastoma in South America in the era of local ocular treatments: A consensus of the Grupo America Latina de Oncologia Pediatrica (GALOP)

Local therapies are increasingly used for ocular preservation in retinoblastoma. In middle-income countries, these techniques pose specific challenges mostly related to more advanced disease at diagnosis. The Grupo de America Latina de Oncología Pediátrica (GALOP) developed a consensus document for the management of conservative therapy for retinoblastoma. Intra-arterial chemotherapy (OAC) is the preferred therapy, except for those with less advanced disease or age younger than 6 months. OAC allowed for a reduction in the use of external beam radiotherapy in our setting. Intravitreal chemotherapy is the preferred treatment for vitreous seeding. Enucleation is the treatment of choice for eyes with advanced disease.     

Human leukocyte antigen-G5 secretion by human mesenchymal stem cells is required to suppress T lymphocyte and natural killer function and to induce CD4+CD25highFOXP3+ regulatory T cells

Adult bone marrow-derived mesenchymal stem cells (MSCs) are multipotent cells that are the subject of intense investigation in regenerative medicine. In addition, MSCs possess immunomodulatory properties with therapeutic potential to prevent graft-versus-host disease (GvHD) in allogeneic hematopoietic cell transplantation. Indeed, MSCs can inhibit natural killer (NK) function, modulate dendritic cell maturation, and suppress allogeneic T-cell response. Here, we report that the nonclassic human leukocyte antigen (HLA) class I molecule HLA-G is responsible for the immunomodulatory properties of MSCs. Our data show that MSCs secrete the soluble isoform HLA-G5 and that such secretion is interleukin-10-dependent. Moreover, cell contact between MSCs and allostimulated T cells is required to obtain a full HLA-G5 secretion and, as consequence, a full immunomodulation from MSCs. Blocking experiments using neutralizing anti-HLA-G antibody demonstrate that HLA-G5 contributes first to the suppression of allogeneic T-cell proliferation and then to the expansion of CD4(+)CD25(high)FOXP3(+) regulatory T cells. Furthermore, we demonstrate that in addition to their action on the adaptive immune system, MSCs, through HLA-G5, affect innate immunity by inhibiting both NK cell-mediated cytolysis and interferon-gamma secretion. Our results provide evidence that HLA-G5 secreted by MSCs is critical to the suppressive functions of MSCs and should contribute to improving clinical therapeutic trials that use MSCs to prevent GvHD.