Ceftriaxone-Resistant Salmonella enterica Serotype Typhimurium Sequence Type 313 from Kenyan Patients Is Associated with the blaCTX-M-15 Gene on a Novel IncHI2 Plasmid

Multidrug-resistant bacteria pose a major challenge to the clinical management of infections in resource-poor settings. Although nontyphoidal Salmonella (NTS) bacteria cause predominantly enteric self-limiting illness in developed countries, NTS is responsible for a huge burden of life-threatening bloodstream infections in sub-Saharan Africa. Here, we characterized nine S. Typhimurium isolates from an outbreak involving patients who initially failed to respond to ceftriaxone treatment at a referral hospital in Kenya. These Salmonella enterica serotype Typhimurium isolates were resistant to ampicillin, chloramphenicol, cefuroxime, ceftriaxone, aztreonam, cefepime, sulfamethoxazole-trimethoprim, and cefpodoxime. Resistance to β-lactams, including to ceftriaxone, was associated with carriage of a combination of bla_CTX-M-15, bla_OXA-1, and bla_TEM-1 genes. The genes encoding resistance to heavy-metal ions were borne on the novel IncHI2 plasmid pKST313, which also carried a pair of class 1 integrons. All nine isolates formed a single clade within S. Typhimurium ST313, the major clone of an ongoing invasive NTS epidemic in the region. This emerging ceftriaxone-resistant clone may pose a major challenge in the management of invasive NTS in sub-Saharan Africa.     

Ultrastructural changes during spermatogenesis,biochemical and hormonal evidences of testicular toxicity caused by TBT in freshwater prawn Macrobrachium rosenbergii (De Man, 1879)

The present investigation documents the impact of tributyltin (TBT) on the ultrastructural variation of spermatogenesis in freshwater prawn Macrobrachium rosenbergii. The environmentally realistic concentration of TBT can cause damages to the endocrine and reproductive physiology of crustaceans. In this context, three concentrations viz. 10, 100, and 1000 ng/L were selected and exposed to prawns for 90 days. The TBT exposed prawn exhibited decrease the reproductive activity as evidenced by sperm count and sperm length compared to control. Histopathological results revealed the retarded testicular development, abnormal structure of seminiferous tubule, decrease in the concentration of spermatozoa, diminution of seminiferous tubule membrane, abundance of spermatocytes and vacuolation in testis of treated prawns. Ultrastructural study also confirmed the impairment of spermatogenesis in treated prawns. Furthermore, radioimmunoassay (RIA) clearly documented the reduction of testosterone level in TBT exposed groups. Thus, TBT substantially reduced the level of male sex hormone as well as biochemical constituents which ultimately led to impairment of spermatogenesis in the freshwater male prawn M.rosenbergii. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 1171–1181, 2014.     

Phase 2 study of pegylated liposomal doxorubicin, vincristine, decreased-frequency dexamethasone, and thalidomide in newly diagnosed and relapsed-refractory multiple myeloma

OBJECTIVE: To evaluate the efficacy and safety of adding thalidomide to the pegylated liposomal doxorubicin, vincristine, and decreased-frequency dexamethasone (DVd) regimen for multiple myeloma. PATIENTS AND METHODS: Patients newly diagnosed as having active multiple myeloma and those with relapsed-refractory disease were studied between August 2001 and October 2003. Patients received DVd as previously described. Thalidomide was given at 50 mg/d orally and the dose increased slowly to a maximum of 400 mg/d. At the time of best response, patients received maintenance prednisone, 50 mg orally every other day, and daily thalidomide at the maximum tolerated dose for each patient. The primary end point was the rate of complete responses plus very good partial responses as defined by the European Group for Blood and Marrow Transplantation criteria and the Intergroupe Fran?ais du Myélome, respectively. RESULTS: Of 102 eligible patients, 53 were newly diagnosed as having multiple myeloma, and 49 had been previously treated for multiple myeloma. The complete response plus very good partial response rate was 49% and 45%, with an overall response rate of 87% and 90% for patients with newly diagnosed and previously treated multiple myeloma, respectively. Furthermore, better responses were associated with improved progression-free and overall survival. The most common grade 3 and 4 adverse events were thromboembolic events (25%), peripheral neuropathy (22%), and neutropenia (14%). CONCLUSIONS: The addition of thalidomide to the DVd regimen significantly improves the response rate and quality of responses compared with the DVd regimen alone. This improvement is associated with longer progression-free and overall survival. The rate of observed quality responses is comparable to responses seen with high-dose therapy.