Plant Virus-Like Particles for RNA Delivery.

Plant viruses such as brome mosaic virus and cowpea chlorotic mottle virus are effectively purified through PEG precipitation and sucrose cushion ultracentrifugation. Increasing ionic strength and an alkaline pH cause the viruses to swell and disassemble into coat protein subunits. The coat proteins can be reassembled into stable virus-like particles (VLPs) that carry anionic molecules at low ionic strength and through two-step dialysis from neutral pH to acidic buffer. VLPs have been extensively studied due to their ability to protect and deliver cargo, particularly RNA, while avoiding degradation under physiological conditions. Furthermore, chemical functionalization of the surface of VLPs allows for the targeted drug delivery. VLPs derived from plants have demonstrated great potential in nanomedicine by offering a versatile platform for drug delivery, imaging, and therapeutic applications.

TCF7L2 is associated with high serum triacylglycerol and differentially expressed in adipose tissue in families with familial combined hyperlipidaemia.

AIMS/HYPOTHESIS: Common DNA variants of the transcription factor 7-like 2 gene (TCF7L2) are associated with type 2 diabetes. Familial combined hyperlipidaemia (FCHL) is characterised by hypertriacylglycerolaemia, hypercholesterolaemia, or both. Additionally, disturbances in glucose metabolism are commonly seen in FCHL. Therefore, we hypothesised that TCF7L2 may contribute to the genetic susceptibility for this common dyslipidaemia. METHODS: We investigated the effect of the TCF7L2 variants, rs7903146 and rs12255372, on FCHL and its component traits triacylglycerol (TG), total cholesterol (TC) and apolipoprotein B (ApoB) in 759 individuals from 55 Mexican families. As a replication sample, 719 individuals from 60 Finnish FCHL families were analysed. We also used quantitative RT-PCR to evaluate the transcript levels of TCF7L2 in 47 subcutaneous fat biopsies from unrelated Mexican FCHL and normolipidaemic participants. RESULTS: Significant evidence for association was observed for high TG for the T alleles of rs7903146 and rs12255372 (p = 0.005 and p = 0.01) in Mexican FCHL families. No evidence for association was observed for FCHL, TC, ApoB or glucose in Mexicans. When testing rs7903146 and rs12255372 for replication in Finnish FCHL families, these single nucleotide polymorphisms were associated with TG (p = 0.01 and p = 0.007). Furthermore, we observed statistically significant decreases in the mRNA levels (p = 0.0002) of TCF7L2 in FCHL- and TG-affected individuals. TCF7L2 expression was not altered by the SNP genotypes. CONCLUSIONS/INTERPRETATION: These data show that rs7903146 and rs12255372 are significantly associated with high TG in FCHL families from two different populations. In addition, significantly decreased expression of TCF7L2 was observed in TG- and FCHL-affected individuals.

[Results of the participation of resident physicians in the surgical treatment of gallbladder lithiasis]. / Resultados de la participación de médicos residentes en el tratamiento quirúrgico de la litiasis vesicular.

The aim of this retrospective study was to evaluate the impact of resident participation in the results of surgical treatment in 1149 consecutive patients operated for biliary disease between January, 1980 and December, 1987 at the Instituto Nacional de la Nutrición "Salvador Zubirán". Patients were divided in three groups: GROUP I. 640 cases treated by surgical residents under a senior surgeon supervision. GROUP II. 168 patients operated by the chief surgical resident. GROUP III. 341 patients treated by senior staff surgeons. Age, sex and risk factors were similar between groups. Residents performed more operative cholangiograms (p less than 0.05). In general, senior surgeons performed more transduodenal sphincteroplasties (p less than 0.05) and other additional procedures like appendectomies and gastrostomies during the same surgery. Wound infection was more frequent in group III patients (p less than 0.005) but there was no significant clinical difference in other postoperative complications like intraabdominal abscess, bile fistula, wound dehiscence, intraabdominal bleeding, iatrogenic injury of the biliary tract, and residual common duct stone. The duration of the in-hospital convalescence period was similar in all three groups. The mortality rate for the total series was 2.2%. In group II there were more patients affected for acute cholecystitis, and more patients died postoperatively (p = less than 0.01). We may consider this difference attributable to the more complex patients handled by the chief resident. Mortality rate among patients with chronic biliary tract disease was less than 1%. We were not able to demonstrate any significant difference in mortality and complication rates between those patients operated by residents, chief residents and senior surgeons.(ABSTRACT TRUNCATED AT 250 WORDS)

[Bacterial count as an infection prognostic factor in the delayed primary closure of abdominal surgical wounds]. / La cuenta bacteriana como factor pronóstico de infección en el cierre primario tardío de heridas quirúrgicas abdominales.

STUDY OBJECTIVE: To determine the prognostic value of the soft-tissue biopsy to handle contaminated or infected surgical wounds with delayed primary closure. DESIGN: Comparative, prolective, blind and observational. PLACE: Referral tertiary care center. PATIENTS: We included 70 patients distributed in two groups: Group I: 50 patients who underwent contaminated or infected abdominal surgery; and Group II: 20 patients who underwent clean or clean contaminated abdominal surgery and developed surgical wound abscess. INTERVENTIONS: Daily cleaning and water irrigation and periodic debridement were done in all the cases; after five days (excluding infection), two tissue biopsies for quantitative culture and wound closure were performed. MEASUREMENTS AND MAIN RESULTS: In Group I, nine of 26 patients (35%) with positive culture (greater than 10(5) colony forming units/g) developed infection and none of 24 with negative culture (p less than 0.01, Fisher); the negative predictive value (nPV) was 100% and the positive predictive value (pPV) was 35%. In Group II, seven of 12 patients with positive culture and one of eight with negative culture developed infection (p less than 0.05); the nPV was 87% and the pPV was 58%. CONCLUSIONS: The biopsy of soft-tissue seems to be a helpful tool for the treatment and prognosis of infected or contaminated surgical wounds.

[Splenectomy in idiopathic thrombocytopenic purpura]. / Esplenectomía en púrpura trombocitopénica idiopática.

Between January 1976 and December 1987, 44 patients with idiopathic thrombocytopenic purpura were submitted to splenectomy. This study analyzes the results of treatment and the usefulness of several prognostic markers. There were 38 female patients and six males with a median age of 28.5 years (range 11 to 66 years). Forty two out of 44 patients received preoperative steroids. Seventy five percent achieved a satisfactory response to this treatment but 31 relapsed (in eight recurrence was observed when the steroid dose was tapered). Eleven patients persisted symptomatic notwithstanding medical treatment. In two cases splenectomy was performed as an emergency procedure, and in one patient who was already in remission with previous steroid treatment, splenectomy was performed for other medical reasons. Operative mortality rate was 4 percent, and five patients developed postoperative complications (three had pneumonia, one pulmonary thromboembolism and one would infection). Eighty four percent of the patients were free of disease at one year followup survival at 10 year period was 80 percent. No correlation was found between age, duration of symptoms, previous response to steroids or time-period of medical treatment with the results obtained with splenectomy.

[Immunoreactive urinary thromboxane B2 in experimental mesenteric thrombosis in dogs]. / Tromboxano B2 urinario inmunorreactivo en trombosis mesentérica experimental en perros.

Thromboxane B2 (TxB2) the stable metabolite of thromboxane A2 may be released as a response to ischemia. With the aim of investigating its role as an early diagnostic test in mesenteric thrombosis, immunoreactive TxB2 was measured in urine aliquotes in six sham operated dogs, nine dogs subjected to superior mesenteric artery ligation, and twelve dogs with superior mesenteric vein ligation. One hour urine volumes were collected before surgery and during the eight hours after the experimental procedures, and urinary osmolarities were also determined in each sample. Basal TxB2 levels were comparable in all groups. Although all groups showed a significant and rapid (one hour) increase in TxB2 as a response to surgery, in the controls it returned to normal after six hours, whereas in the rest a continuously increased production persisted throughout the study period. There was no difference in t-test comparisons depending on the sort of thrombosis. In spite of the urinary dilution induced during the study, a persistent increase in TxB2 excretion was found. We conclude that urinary TxB2 levels could prove useful in the early diagnosis of mesenteric ischemia.

[Xanthogranulomatous cholecystitis. Clinical entity or pathologic curiosity]. / Colecistitis xantogranulomatosa. Entidad clínica o curiosidad patológica.

Xanthogranulomatous cholecystitis is an uncommon variety of gallbladder inflammation. Its histologic appearance is quite specific but its clinical characteristics, prognostic and physiopathologic implications are unknown. The present study has the aim of analyzing a group of 40 patients with xanthogranulomatous cholecystitis and another of 80 patients with non-xanthogranulomatous inflammation. The clinical characteristics, risk factors, morphologic expression, complications and mortality of both groups were compared. Diffuse xanthogranulomatous cholecystitis comprised 1.8% of all cholecystectomies done between January 1976 and July 1987. This variety was more frequent in males (p less than .05) without any specific risk factors. There was a higher frequency of acute pyogenic inflammation sometimes associated to extrinsic compression of the biliary duct and fistulization, but without any difference in the overall complication rate or mortality. We conclude that xanthogranulomatous cholecystitis is a specific entity which occurs with a higher frequency in males and that has a different clinical behavior than that of other types of gallbladder inflammation.