A novel method for "Wet" SEM

Progress in the processing of wet tissues, without the need of fixation and complex preparation procedures, may facilitate the microscopic examination of tissues and cells. Microscopic examination of tissues is a central tool in clinical diagnosis as well as in diverse areas of research. The authors present the application of Wet SEM, a technology for imaging fully hydrated samples at atmospheric pressure in a scanning electron microscope (SEM). The technique is based on 2 principles. First, samples are imaged in sealed specimen capsules and are separated from the evacuated interior of the electron microscope by a thin, electron-transparent partition membrane that is strong enough to sustain a 1-atm pressure difference. Second, imaging is done in a SEM, based on detection of backscattered electrons, which penetrate a few microns into the specimen and thus give information on the cellular level.     

Modified Marcy repair for indirect inguinal hernia in children: a 24-year single-center experience of 6826 pediatric patients

Purpose

To evaluate the management and outcomes of modified Marcy repair for inguinal hernia in a large series of children.

Methods

We analyzed the case records of 6826 pediatric patients who underwent surgery for inguinal hernia between January, 1991 and January, 2015 at Split University Hospital in Croatia. The following parameters were examined: sex, age, location of the hernia, intraoperative or postoperative complications, recurrence, and surgical method.

Results

The 6826 patients included 4751 boys and 2075 girls operated on for inguinal hernia. The mean age was 3.5 years, and mean followup was 14 years. Right-side predominance was noted with 59.50 % right hernia repairs, 33.72 % left hernia repairs, and 6.78 % bilateral hernia repairs. There were 6410 (93.90 %) elective procedures and 416 (6.10 %) emergency procedures for incarceration. The mean duration of surgery was 26 min (14–90 min), and the mean hospital stay was 1 day. Marcy repair was the most commonly performed operation (95.76 %), whereas Ferguson’s technique was performed in only 3.98 % of the children. The overall recurrence rate was 0.43 %, with a recurrence rate of 0.36 % for Marcy repair and 1.83 % for Ferguson repair (p = 0.0003).

Conclusion

Modified Marcy hernia repair is a safe and effective procedure for inguinal hernia in children with excellent outcomes and a low incidence of recurrence.

     

MMP-2 and TIMP-2 Expression Correlates with Poor Prognosis in Cervical Carcinoma—A Clinicopathologic Study Using Immunohistochemistry and mRNA in Situ Hybridization

Objective. The spread of malignant neoplasms is closely associated with matrix and basement membrane degradation, mediated by various classes of proteolytic enzymes. Matrix metalloproteinases (MMP) appear to have a key role in the sequence of events that lead to local invasion and metastasis. The present study evaluated the role of matrix metalloproteinase-2 (MMP-2), tissue inhibitor of metalloproteinases-2 (TIMP-2), and membrane-type metalloproteinase (MT1-MMP) in cervical neoplasia.Methods. We have analyzed 49 uterine cervical squamous cell carcinomas, 10 cases of high-grade cervical intraepithelial neoplasia (CIN II–III), and 10 control cervices for the presence of MMP-2, TIMP-2, and MT1-MMP using in situ hybridization. MMP-2 protein expression was evaluated using immunohistochemistry. Results were analyzed for possible correlation with disease outcome.Results. MMP-2, TIMP-2, and MT1-MMP mRNA were localized to both stromal and tumor cells. However, an intense signal for MMP-2 was detected almost exclusively in tumor cells and was uniformly absent from CIN lesions and control cervices. Conversely, intense signals for TIMP-2 and MT1-MMP were detected in both stromal and tumor cells of invasive carcinomas, more often for the former. As with MMP-2, they were absent from CIN lesions. MMP-2 protein expression was enhanced in tumor cells compared to CIN cases and controls, significantly compared to the latter (P = 0.01). The presence of both MMP-2 and TIMP-2 mRNA in tumor cells correlated with advanced stage (P = 0.003 for MMP-2, P = 0.002 for TIMP-2) and with poor survival (P = 0.003 for MMP-2, P = 0.002 for TIMP-2) in univariate analysis. In addition, their presence in tumor cells intercorrelated (P = 0.002). In multivariate survival analysis, MMP-2 presence retained its association with survival (P = 0.004), in addition to patient age (P = 0.027) and advanced stage (P = 0.0002).Conclusions. Both MMP-2 and TIMP-2 have a key role in extracellular matrix invasion in cervical carcinoma, largely through their elaboration by tumor cells. The presence of mRNA for both proteins is interrelated and is associated with poor survival.     

The immediate and short‐term effects of bilateral intrahippocampal depth electrodes on verbal memory

In contrast to previous studies, Ljung et al. provide evidence of permanent cognitive consequences of bilateral intrahippocampal depth electrodes for verbal memory in patients who were not operated or operated in the right temporal lobe. Stimulated by this, we provide historical confirmatory and supplementary evidence of the detrimental effect of bilateral depth electrodes implanted along the longitudinal axis of the hippocampus on verbal learning and especially on delayed verbal memory and recognition performance. This is demonstrated in 31 patients with memory assessments before implantation, after explantation, and 3 months later after left/right temporal lobe surgery. After surgery, significant recovery from postimplantation impairment is found in right temporal patients. Left temporal resection patients stay on the level seen after implantation and do not recover. Surgery, however, has its own effects in addition to the implantation. Intracranial electrodes for electroencephalographic monitoring or electrical stimulation are commonly and increasingly used for diagnosis or treatment in pharmacoresistant epilepsies. Thus, the monitoring of invasive stereotactic approaches is recommended to find safe procedures for the patients. In response to the findings, we restricted indications and used different implantation schemes, different trajectories, and targets to minimize the risk of additional damage.     

New records of Culicoides species (Diptera: Ceratopogonidae) for Bolivia

Culicoides debilipalpis, C insignis, C. lahillei, and C venezuelensis are reported for the first time for Bolivia. The geographical distribution of C. paraensis extends to the Tarija Department.     

Synthesis and Ex Vivo Autoradiographic Evaluation of Ethyl-��-d-galactopyranosyl-(1,4��)-2��-deoxy-2��-[18F]fluoro-��-d-glucopyranoside��A Novel Radioligand for Lactose-Binding Protein: Implications for Early Detection of Pancreatic Carcinomas with PET

Introduction

Previous studies demonstrated that the lactose-binding protein (hepatocellular carcinoma?Cintestine?Cpancreas and pancreatitis-associated proteins (HIP/PAP)) is upregulated >130 times in peritumoral pancreatic tissue as compared to normal pancreatic tissue. Therefore, we developed a new radiolabeled ligand of HIP/PAP, the ethyl-??-d-galactopyranosyl-(1,4??)-2??-deoxy-2??-[¹⁸F]fluoro-??-d-glucopyranoside (Et-[¹⁸F]FDL) for noninvasive imaging of pancreatic carcinoma using positron emission tomography and computerized tomography (PET/CT).

Methods

The novel precursor and radiolabeling methods for synthesis of Et-[¹⁸F]FDL produced no isomers; the average decay-corrected radiochemical yield was 68%, radiochemical purity >99%, and specific activity >74 GBq/µmol. The radioligand properties of Et-[¹⁸F]FDL were evaluated using an ex vivo autoradiography and immunohistochemistry in pancreatic tissue sections obtained from mice-bearing orthotopic pancreatic tumor xenografts.

Results and Discussion

Et-[¹⁸F]FDL binding to peritumoral pancreatic tissue sections strongly correlated with HIP/PAP expression (r?=?0.81) and could be completely blocked by treatment with 1 mM lactose.

Conclusion

These results suggest that Et-[¹⁸F]FDL is a promising agent which should be evaluated for detection of early pancreatic carcinomas by PET/CT imaging.     

Pharmacokinetics and magnetic resonance imaging of biodegradable macromolecular blood‐pool contrast agent PG–Gd in non‐human primates: a pilot study

The purpose of this study was to evaluate poly(L ‐glutamic acid)‐benzyl‐DTPA–Gd (PG–Gd), a new biodegradable macromolecular magnetic resonance imaging contrast agent, for its pharmacokinetics and MRI enhancement in nonhuman primates. Studies were performed in rhesus monkeys at intravenous doses of 0.01, 0.02 and 0.08 mmol Gd/kg. T₁‐weighted MR images were acquired at 1.5 T using fast spoiled gradient recalled echo and fast spin echo imaging protocols. The small‐molecule contrast agent Magnevist was used as a control. PG–Gd in the monkey showed a bi‐exponential disposition. The initial blood concentrations within 2 h of PG–Gd administration were much higher than those for Magnevist. The high blood concentration of PG–Gd was consistent with the MR imaging data, which showed prolonged circulation of PG–Gd in the blood pool. Enhancement of blood vessels and organs with a high blood perfusion (heart, liver, and kidney) was clearly visualized at 2 h after contrast injection at the three doses used. A greater than proportional increase of the area under the blood concentration–time curve was observed when the administered single dose was increased from 0.01 to 0.08 mmol/kg. By 2 days after PG–Gd injection, the contrast agent was mostly cleared from all major organs, including kidney. The mean residence time was 15 h at the 0.08 mmol/kg dose. A similar pharmacokinetic profile was observed in mice, with a mean residence time of 5.4 h and a volume of distribution at steady‐state of 85.5 ml/kg, indicating that the drug was mainly distributed in the blood compartment. Based on this pilot study, further investigations on the potential systemic toxicity of PG–Gd in both rodents and large animals are warranted before testing this agent in humans. Copyright © 2011 John Wiley & Sons, Ltd.