Hypothermia at 10 degrees C reduces neurologic injury after hypothermic circulatory arrest in the pig.

BACKGROUND: We have previously reported that sensory, motor neocortex, and hippocampus are selectively vulnerable to injury in an acute porcine model of HCA at 18 degrees C. This study was undertaken to assess whether further cooling to 10 degrees C can reduce neurological injury during HCA. METHODS: Twelve piglets underwent 75 minutes of HCA at 18 degrees C (n = 6) and 10 degrees C (n = 6). Four served as normal controls. After gradual rewarming and 80 minutes of reperfusion, treatment animals were sacrificed and brains were perfusion-fixed and cryopreserved. Regional patterns of neuronal apoptosis after HCA were characterized by in situ DNA fragmentation using TUNEL histochemistry. Hematoxylin and eosin histology was used to characterize cell damage morphologically. TUNEL-positive cells were scored on a scale of 0 to 5. Grade 0: no TUNEL-positive cells; Grade 1: < 10%; Grade 2: 10% to 25%, Grade 3: 25% to 50%, Grade 4: 50% to 75%; and Grade 5: > 75%. RESULTS: TUNEL-positive cells indicating DNA fragmentation were scored in the motor and sensory neocortex, hippocampus, cerebellum, thalamus, and medulla of animals treated with 18 degrees C and 10 degrees C HCA and were significantly greater than in normal controls. Profound cooling to 10 degrees C resulted in a significant reduction of neuronal injury in the neocortex and hippocampus. CONCLUSIONS: This data support that cerebral protection may be better at very cold temperatures compared to 18 degrees C hypothermia. Regions selectively vulnerable to neuronal injury are offered more neural protection by profound hypothermia. These affects are observed in the acute state, suggesting activation of the apoptotic mechanisms at early stages can be inhibited by profound hypothermia.

Apoptosis bcl-2 and nitrotyrosine expression in an angioplasty-restenosis rabbit: an experimental model.

Apoptosis has been suggested to have an important role in the pathogenesis of restenosis in addition to cell migration and proliferation. The aim of the present study was to investigate in an experimental in vivo model the occurrence of apoptosis postangioplasty and its relation to bcl-2 and peroxynitrite detection. Eighteen hypercholesterolemic rabbits underwent transluminal angioplasty of the right iliac artery. The rabbits were sacrificed on the 1st, 2nd, 3rd, 7th, 15th, and 28th day postangioplasty (3 animals per time point) and both the angioplasted and non-injured arteries were studied. Apoptosis was assessed by the terminal uridine nick-end labeling method (TUNEL). Bcl-2 and peroxynitrite were detected by immunochemistry using anti-bcl-2 and anti-nitrotyrosine antibodies. In the angioplasted arteries the number of apoptotic cells was

Effect of profound hypothermia during circulatory arrest on neurologic injury and apoptotic repressor protein Bcl-2 expression in an acute porcine model.

OBJECTIVES: We reported that the neocortex and hippocampus are selectively vulnerable to injury in an acute porcine model of hypothermic circulatory arrest at 18 degrees C. We hypothesize that further cooling to 10 degrees C could reduce neurologic injury in these regions. To further elucidate the mechanisms of neurologic injury and protection, we assessed the expression of the anti-apoptotic protein Bcl-2. METHODS: Twelve piglets underwent 75 minutes of hypothermic circulatory arrest at 18 degrees C (n = 6) and 10 degrees C (n = 6). After gradual rewarming and reperfusion, animals were put to death and brains were perfusion-fixed and cryopreserved. Regional patterns of neuronal apoptosis after hypothermic circulatory arrest were characterized by in situ DNA fragmentation with terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) histochemistry. Bcl-2 protein expression was characterized with immunohistochemistry. Statistical comparisons were made by t test, analysis of variance, and Mann-Whitney U test, as appropriate. RESULTS: Concentrations of TUNEL(+) cells were significantly lower after profound hypothermia at 10 degrees C compared with 18 degrees C hypothermia in the sensory and motor neocortex and hippocampus (t test, P < .0001; P < .006; P < .006, respectively). Positive Bcl-2 immunostaining was observed only in the motor and sensory neocortex and hippocampus after 18 degrees C hypothermic circulatory arrest. Profound cooling to 10 degrees C resulted in a significant increase in Bcl-2 immunostaining in the motor and sensory cortex as compared with 18 degrees C (Mann-Whitney U test, P < .05). CONCLUSIONS: Deep hypothermia at 10 degrees C protects the neocortex and hippocampus from insult during hypothermic circulatory arrest as suggested by significantly reduced TUNEL(+) staining in these areas. Although a concomitant increase in Bcl-2 expression was observed in the neocortex at 10 degrees C, it remains unclear whether profound hypothermia deters from neuronal injury by activation of the anti-apoptotic protein Bcl-2.

A freeze-dried fibrin disc as a biodegradable drug release matrix.

A fibrin clot loaded with soluble tetracycline (TET) was prepared and lyophilized to make discs of a size and shape to use as a drug delivery matrix. On subcutaneous implantation of these discs in mice, they were found to have degraded in 15 days as evidenced by gross and histological examination. The in vitro discharge kinetics of tetracycline from the disc into phosphate buffered saline (PBS) and human serum were compared. It was observed that the release rate of tetracycline from the matrix into serum remained steady from day 1 to day 12, maintaining sufficient concentration that may be required to control microbial growth in the medium. Two different concentrations of fibrinogen were used to fabricate discs denoted as FG200 and FG100, and in both cases the retention rate was comparable when the study medium was serum. In contrast, when suspended in PBS instead of serum, the delivery of the drug into the medium was found to be high for up to the 3rd day when a sharp decline in discharge was observed. The fibrinogen used is a factor that determines not only the longevity of discharge but also fibrinolysis. The degradation of the disc in vitro was visible when the discs were suspended in the buffer, and correspondingly fibrin degradation product (FDP) measured in the medium using an antibody-based assay system was high. Fibrin disc is haemostatic and biodegradable in vivo, and in vitro release of a small molecule at a controlled rate is demonstrated here. Hence, it may be a suitable candidate as a drug delivery implant for short-term use.

Successful treatment of human immunodeficiency virus-related Castleman's disease: a case report and literature review.

Multicentric Castleman's disease is increasingly recognized as an aggressive illness with a rapidly fatal outcome in human immunodeficiency virus (HIV)-infected patients. In the absence of optimal therapy, various therapeutic interventions have been tested with disappointing results; only five reports with a successful outcome have been described. Presented herein is a 66-year-old HIV-infected man with multicentric Castleman's disease. Early administration of cyclophosphamide, doxorubicin, vincristine and prednisone resulted in prolonged clinical recovery. The relevant literature is also reviewed.

An improved method for isolation of anti-viper venom antibodies from chicken egg yolk.

The production of antibodies and its purification from mammalian blood has been found low yielding and laborious. Therefore, anti snake venom antibodies for therapeutic use is obtained mostly as polyvalent whole serum or partially purified polyvalent immunoglobulin. The side effects of anti snake venom (ASV) therapy are mainly serum sickness and renal failure, which may be reduced by using sufficiently pure antibodies. Therefore, we have standardized a simple method for production of purified antivenom. Here, we present the development of polyclonal antibodies against viper venom in hens and its isolation from the egg yolk of immunized birds. We have modified the reported methods of purification of immunoglobulin from egg yolk, and thus yielded 90% purity of the protein. The modified method involves only two steps, such as removal of lipids from the diluted egg yolk by a freeze-thaw cycle and centrifugation, followed by gel filtration on Biogel P-150. The advantages are that the process is very simple, and from one egg, 100+/-20 mg of pure immunoglobulin is obtained. The antibodies are present in the egg for up to 100 days after the immunization. Thus, using small amounts of venom, a large quantity of the immunoglobulin is obtained in a sufficiently pure form. The antigen binding ability of the pure antibody is found good by the Ouchterlony's double diffusion experiment.

Update of the role of surgery in the multimodal treatment of MALT gastric lymphomas.

BACKGROUND: Primary gastric non-Hodgkin's lymphoma is a well-defined clinicopathological entity with a distinct histological spectrum and indolent course. Its optimal management still remains controversial. In this study we present our experience with surgery being part of the multimodal treatment and we compare our results with those referred to in the world literature. MATERIALS AND METHODS: Sixty-five patients (37 males, 28 females) with gastric MALT lymphoma were retrospectively analyzed. Forty-seven patients underwent curative resection, eleven received chemotherapy as primary treatment, two patients received radiotherapy before any other treatment and five patients received combined chemo-radiation therapy. RESULTS: For the early stages of the disease (I-III), radical resection offered a two-year survival rate of 100% and 93%, respectively, and a five-year survival of 85% and 67%, respectively. For those stage I patients, who were managed surgically followed by adjuvant therapy, the two- and five-year survival was 90% and 78%, respectively. For stage II patients for whom chemo-radiation therapy followed surgery, the two- and five-year survival was 88% and 65%, respectively. CONCLUSION: In view of the results of our study, surgery is an adequate treatment modality for the early stages of the disease. The addition of radiotherapy or chemotherapy does not improve the overall survival. Conversely, for the advanced stages (II2-IV), primary chemotherapy is the best treatment option with surgery being reserved for cytoreduction or chemo-radiotherapy-induced complications.