Enhanced rates and magnitude of immune responses detected against an HIV vaccine: effect of using an optimized process for isolating PBMC

Quantitative analysis of cell-mediated immune responses induced by candidate HIV vaccines requires robust procedures for collecting and processing human peripheral mononuclear blood cells (PBMCs). We evaluated several parameters in order to optimize a sample handling process that would be suitable for a multicenter clinical trial. Among the findings, systematic increases in the magnitude of IFN-gamma ELISpot responses were observed when the time from blood collection to PBMC freezing was reduced to <12 h. By implementing these improvements within an ongoing clinical trial, the estimated immunologic response rates to an adenovirus- based HIV vaccine increased by more than 20 percentage points to approximately 80% of the vaccine recipients against any of the vaccine antigens and the average levels of T cell response improved more than 3-fold. These studies establish the importance of optimal conditions for PBMC collection and handling to the success of a clinical development program.     

Substitution of oral (18)F-FDG for intravenous (18)F-FDG in PET scanning

The aim of this study was to see whether oral administration of (18)F-FDG could be substituted-without significant loss of information-for intravenous injection of (18)F-FDG in patients with difficult intravenous access of any cause, such as that often seen in cancer patients after many cycles of chemotherapy. METHODS: PET after both oral and intravenous administration of (18)F-FDG was performed on 2 healthy volunteers and 7 patients. An interval of 48 h was maintained between the oral administration and the intravenous administration. All scans were visually analyzed. Semiquantitative analysis of specific areas was done by calculating standardized uptake values (SUVs). Scanning was performed 60 min after intravenous tracer administration and 90 min after oral tracer administration. RESULTS: All lesions seen after intravenous administration were visualized on the oral study as well. SUVs were lower on the oral study than on the intravenous study. CONCLUSION: Oral (18)F-FDG can successfully be substituted for intravenous (18)F-FDG in patients with difficult intravenous access. However, because of the large amount of (18)F-FDG retained in the gut, careful interpretation will be required when disease of the gastrointestinal tract is being evaluated.     

Detection of unsuspected metachronous second primary malignancy giving rise to supposed "non-iodine avid metastasis" in differentiated thyroid carcinoma

We, herein, explore the added aspect of FDG-PET to investigate an I-131 scan negative for differentiated thyroid carcinomas (DTCs), namely the identification of previously unsuspected second primary malignancies. We present 2 cases of DTC, showing metastatic lesions in the liver and the lungs but showing no I-131 uptake and hence was initially thought to be due to dedifferentiation. FDG-PET was performed as a part of a study to prospectively evaluate its usefulness in "noniodine concentrating metastases" of DTC and to look into the validity of the traditionally described "flip-flop" between I-131 whole-body scan (reflecting the sodium-iodide symporter status in the tumor) and FDG-PET (reflecting the glucose transporter status in the tumor). In addition to the uptake in the metastatic sites, FDG-PET demonstrated unusually intense foci of hypermetabolism in the gut and the right kidney. These were subsequently found to harbor clinically silent coexisting second primary malignancies at those sites giving rise to hepatic and pulmonary metastases. Thus FDG-PET, in both these cases, provided the correct explanation for the absence of radioiodine uptake in the metastatic sites, which were otherwise thought to be due to the loss of differentiation of DTC. This role of FDG-PET in incidentally detecting a coexisting additional primary malignancy giving rise to extensive metastases is relatively unexplored and adds a new dimension to its routine application of a metastatic survey in so-called noniodine avid thyroid carcinoma, which can have a significant bearing on subsequent patient management.     

Collagen matrix duraplasty for cranial and spinal surgery: a clinical and imaging study

OBJECT: The repair of dural defects is controversial in contemporary neurosurgery. To date, collagen-based products remain a continued area of interest in the development of dural grafts. The authors conducted a prospective case-control study in which they evaluated collagen matrix in the repair of dural defects following cranial and spinal surgery by using specific clinical and magnetic resonance (MR) imaging outcome measures. METHODS: Enrolled in the study were 79 patients, 36 male (45.6%) and 43 female (54.4%), with a mean age of 53 +/- 15.8 years. The pathological diagnosis was brain tumor in 49 cases (62%), vascular conditions in 16 (20.2%), degenerative spine in 10 (12.7%), trauma in two (2.5%), and other in two (2.5%). Most of the patients underwent supratentorial craniotomy (57; 72.2%), whereas 11 patients (13.9%) each underwent posterior fossa and spinal surgery. Sixty-three patients (79.7%) completed the study, which included clinical and MR imaging evaluations at 3 months postsurgery. There were no cerebrospinal fluid (CSF) leaks or delayed hemorrhages. The neurosurgical wound infection rate was 3.8%: superficial wound infection in two cases and deep infection and brain abscess in one case (recurrent brain tumor following radiation therapy). Among the 63 patients in whom 3-month postsurgery imaging data were available, asymptomatic small pseudomeningoceles were detected on MR imaging in two (3.2%); a minor subgaleal fluid collection, which resolved spontaneously, was apparent in another patient (1.6%). Nonspecific dural enhancement was demonstrated on images obtained in seven patients (11.1%), and asymptomatic spinal epidural enhancement was observed on images obtained in two of three patients who had undergone lumbar laminectomy for spinal stenosis. CONCLUSIONS: When used as a dural onlay graft, collagen matrix had a 100% CSF containment rate but might be associated with occult radiological abnormalities.     

Wettability and kinetics of hydroxyapatite precipitation on a laser-textured Ca–P bioceramic coating

Surface-textured calcium phosphate coatings at four different length scales were synthesized on titanium-based alloys using a pulsed Nd:YAG laser system by a direct melting technique. The textures were obtained by varying the laser spot overlap with a change in laser traverse speed. Surface roughness measurements of the textured coatings carried out using a white light interferometer indicated a decrease in roughness with increasing laser scan speed. Wettability of the coated samples measured using a static sessile drop technique demonstrated an increased hydrophilicity with increasing laser scan speed. The influence of such textures and the associated surface roughness on the precipitation kinetics of hydroxyapatite (HA) during immersion in simulated body fluid (SBF) was the prime focus of the present paper. The mineralized samples obtained after immersion in SBF were characterized using X-ray diffraction, energy-dispersive spectroscopy and scanning electron microscopy to understand the kinetics of HA precipitation. The results thereafter confirmed that the precipitation kinetics of HA was strongly modulated by the varying surface roughness.     

Evaluation of protective efficacy of Spirulina platensis against collagen-induced arthritis in rats

Aim  To assess the protective efficacy of Spirulina platensis against collagen-induced arthritis (CIA) in female Wistar rats based on the changes in paws thickness, serum albumin, cholesterol, lipid peroxidation, alkaline phosphatase and acid phosphatase activities and histology of paw joints. Methods  Arthritis was induced by intradermal injection of Collagen and Freund’s adjuvant incomplete suspension at several sites on the back with a dose of 2 mg kg⁻¹ of body weight and boosted with 0.1 ml intradermally at the base of the tail. CIA rats were orally treated with 200 and 400 mg kg⁻¹ per oral of S. platensis from 0 to 45th day. Results   S. platensis at 400 mg kg⁻¹ per oral significantly elevates serum albumin and decreases the serum cholesterol, alkaline phosphatase and acid phosphatase activities, lipid peroxidation, paw thickness as well as normalize the joint histopathology of CIA rats. Conclusions   S. platensis (400 mg kg⁻¹) significantly normalizes changes observed in arthritic rats to near normal conditions, indicates that S. platensis has promising protective efficacy against CIA rats.     

Assessing specificity for immunogenicity assays

Developing sensitive and specific bioanalytical assays for measuring the immunogenicity of biological therapeutics has become an integral component of the drug-development process. The strategy for measuring these immune responses involves performing sensitive screening assays that are capable of detecting low levels of both low- and high-affinity antibodies. However, having sensitive assays inherently results in a certain rate of false-positivity. Hence, developing steps to determine specificity in these assays is important to confirm the presence of antidrug antibodies. The specificity assays are defined by the ability of an assay to score a positive result if the serum sample contains an antibody that can bind and/or neutralize the therapeutic protein. Here, we discuss the methodologies for determining specificity in the bioanalytical assays used for measuring antidrug antibodies. These methods will provide investigators and regulators with guidelines to develop and review assays to measure antidrug antibodies, which can specifically interfere with the actions of the drug and/or influence the safety profile of the therapeutic proteins.     

Implication of BRCA2 -26G>A 5' untranslated region polymorphism in susceptibility to sporadic breast cancer and its modulation by p53 codon 72 Arg>Pro polymorphism

Introduction  

The absence of mutation or promoter hypermethylation in the BRCA2 gene in the majority of breast cancer cases has indicated alternative ways of its involvement, deregulated expression being one possibility. We show how a polymorphism in the 5' untranslated region (UTR) of BRCA2 can serve as one such factor. Based on the hypothesis that variants of genes involved in the same pathway can influence the risk provided for breast cancer, the status of p53 codon 72 polymorphism was also investigated and a possible interaction between the polymorphisms was examined.     

Bone metastasis from ovarian cancer

We report a case of epithelial ovarian cancer, which presented with lumbar vertebral metastasis soon after treatment, as a part of distant spread. This patient was then treated by palliative radiotherapy and put on second line chemotherapy i.e, Topotecan. She responded to treatment well.