Perspectives on the Trypanosoma cruzi-host cell receptor interaction

Chagas disease is caused by the parasite Trypanosoma cruzi. The critical initial event is the interaction of the trypomastigote form of the parasite with host receptors. This review highlights recent observations concerning these interactions. Some of the key receptors considered are those for thromboxane, bradykinin, and for the nerve growth factor TrKA. Other important receptors such as galectin-3, thrombospondin, and laminin are also discussed. Investigation into the molecular biology and cell biology of host receptors for T. cruzi may provide novel therapeutic targets

Inside the guts of wood-eating catfishes: can they digest wood?

To better understand the structure and function of the gastrointestinal (GI) tracts of wood-eating catfishes, the gross morphology, length, and microvilli surface area (MVSA) of the intestines of wild-caught Panaque nocturnus, P. cf. nigrolineatus “Marañon”, and Hypostomus pyrineusi were measured, and contrasted against these same metrics of a closely related detritivore, Pterygoplichthys disjunctivus. All four species had anatomically unspecialized intestines with no kinks, valves, or ceca of any kind. The wood-eating catfishes had body size-corrected intestinal lengths that were 35% shorter than the detritivore. The MVSA of all four species decreased distally in the intestine, indicating that nutrient absorption preferentially takes place in the proximal and mid-intestine, consistent with digestive enzyme activity and luminal carbohydrate profiles for these same species. Wild-caught Pt. disjunctivus, and P. nigrolineatus obtained via the aquarium trade, poorly digested wood cellulose (<33% digestibility) in laboratory feeding trials, lost weight when consuming wood, and passed stained wood through their digestive tracts in less than 4 h. Furthermore, no selective retention of small particles was observed in either species in any region of the gut. Collectively, these results corroborate digestive enzyme activity profiles and gastrointestinal fermentation levels in the fishes’ GI tracts, suggesting that the wood-eating catfishes are not true xylivores such as beavers and termites, but rather, are detritivores like so many other fishes from the family Loricariidae

Sustaining Interferon Induction by a High-Passage Atypical Porcine Reproductive and Respiratory Syndrome Virus Strain

Partial funding for Open Access provided by the UMD Libraries' Open Access Publishing Fund.Porcine reproductive and respiratory syndrome virus (PRRSV) strain A2MC2 induces type I interferons in cultured cells. The objective of this study was to attenuate this strain by serial passaging in MARC-145 cells and assess its virulence and immunogenicity in pigs. The A2MC2 serially passaged 90 times (A2MC2-P90) retains the feature of interferon induction. The A2MC2-P90 replicates faster with a higher virus yield than wild type A2MC2 virus. Infection of primary pulmonary alveolar macrophages (PAMs) also induces interferons. Sequence analysis showed that the A2MC2-P90 has genomic nucleic acid identity of 99.8% to the wild type but has a deletion of 543 nucleotides in nsp2. The deletion occurred in passage 60. The A2MC2-P90 genome has a total of 35 nucleotide variations from the wild type, leading to 26 amino acid differences. Inoculation of three-week-old piglets showed that A2MC2-P90 is avirulent and elicits immune response. Compared with Ingelvac PRRS® MLV strain, A2MC2-P90 elicits higher virus neutralizing antibodies. The attenuated IFN inducing A2MC2-P90 should be useful for development of an improved PRRSV vaccine

Supracricoid partial laryngectomy in the management of t3 laryngeal cancer

Objective. To evaluate the oncologic results only in T3 glottic and supraglottic cancers regarding supracricoid partial laryngectomy (SCPL) not requiring total laryngectomy and to assess functional results by self-evaluation by the patient. Study Design. Case series with medical record review. Setting. Single tertiary care center. Subjects and Methods. Thirty-two patients with laryngeal squamous cell carcinoma, previously untreated, who underwent SCPL with cricohyoidopexy or cricohyoidoepiglottopexy were reviewed. Results. At 1, 3, and 5 years, the disease-free survival rates were 96.9%, 89.4%, and 78.2%; overall survival rates were 96.9%, 93.2%, and 87.3%; local control and locoregional control rates were 100%, 96.2%, and 96.2%; and distant metastasis-free survival rates were 100%, 100%, and 88.2%, respectively. Aspiration pneumonia was the most common complication observed. The 3 laryngeal functions (speech, swallowing, and breathing) were spared in 83.9% of patients. Conclusion. Supracricoid partial laryngectomy for selected glottic and supraglottic T3 tumors has excellent oncologic and functional results