Somatic mitochondrial mutation in gastric cancer.

Likely hot spots for mutations are mitochondrial sequences as there is less repair and more damage by carcinogens compared with nuclear sequences. A somatic 50-bp mitochondrial D-loop deletion was detected in four gastric adenocarcinomas. The deletion included the CSB2 region and was flanked by 9-bp direct repeats. The deletion was more frequent in adenocarcinomas arising from the gastroesophageal junction (4/32, 12.5%) compared with more distal tumors (0/45). Topographical analysis revealed the absence of the deletion from normal tissues except in focal portions of smooth muscle in one case. In two cases, apparent mutant homoplasmy was present throughout two tumors, including their metastases. In the two other cases, the mutation was present in only minor focal portions ( < 5%) of their primary tumors. These findings document the presence of somatic mitochondrial alterations in gastric cancer, which may reflect the environmental and genetic influences operative during tumor progression.     

Comparison of "host cell infiltrates" in patients with follicular lymphoma with and without spontaneous regression

The "host cell infiltrates" in five patients with low-grade follicular lymphoma who had spontaneous regression without therapy were studied with the use of immunohistochemical methods applied to frozen sections. These infiltrates were compared with the "host cell infiltrates" in six patients with follicular lymphoma with progressive disease. The group with progressive disease was selected to be similar to the group with spontaneous regression in age, sex, histologic characteristics, and stage of disease. The patients with spontaneous regression had significantly more T-helper cells in the host cell infiltrate than the control patients. There were no statistically significant differences between the two groups in numbers of cytotoxic/suppressor T-cells, macrophages, Tac-positive cells, Leu-7-positive cells, or proliferating cells.     

Bearing exchange in the management of pseudotumours

Introduction

Soft tissue reactions following metal-on-metal (MoM) arthroplasty of the hip have been under considerable discussion. These reactions are seen following both hip resurfacing and MoM total hip arthroplasty (THA). The phenomenon may arise owing to shedding of metal particles in high wear states, hypersensitivity with normal metal wear rates or a combination of the two.

Methods

Three patients were identified who had developed a soft tissue reaction (pseudotumour) following MoM hip resurfacing procedures. The prostheses were revised to ceramic-on-ceramic (CoC) THA with only minimal debridement of the pseudotumour. Pre and postoperative magnetic resonance imaging was performed to assess the size of the lesions.

Results

Progressive and satisfactory resolution of the associated pseudotumours was identified following revision of the prostheses to CoC THA.

Conclusions

In the early stages of pseudotumour formation following MoM hip resurfacing, this potentially devastating condition can be managed adequately with revision to a CoC bearing THA with minimal soft tissue excision.     

The leftward deletion alpha-thal-2 haplotype in a black subject with hemoglobin SS

We have identified a black individual with homozygous sickle cell anemia who is the silent carrier of alpha-thalassemia (genotype - alpha/alpha alpha) due to heterozygosity for the leftward deletion alpha-thal-2 haplotype. This deletion has not been described previously in a black subject and is the only leftward deletion that we have found among 255 alpha-thal-2 chromosomes from sickle cell subjects. Its effects on the clinical, hematologic, biosynthetic, and cellular pathology of sickle cell anemia resemble those reported for the common alpha-thalassemia genotypes of the black population.     

假细锥香茶菜新二萜成分——假细锥甲素的结构

从假细锥香茶菜(Rabdosia coetsoides C.Y.Wu)叶分离得到新二萜成分,根据紫外光谱、红外光谱、质谱、核磁共振氢谱及碳谱等分析,推定了化学结构,并经X-射线衍射确证,命名为假细锥甲素。     

The effect of tumor necrosis factor on human sperm motility in vitro

Tumor necrosis factor (TNF alpha) is present in elevated levels in peritoneal fluid from infertile women with endometriosis. The effect of TNF alpha on human sperm motility in vitro was evaluated utilizing peritoneal fluid from infertile women with minimal endometriosis containing 0, 100, 400, or 800 U of TNF alpha/ml as well as similar concentrations of recombinant human TNF alpha. No reduction in progressive and total motility was found at recombinant TNF alpha concentrations of 100 U ml. However, 500 and 1000 U of recombinant TNF alpha/ml caused a significant reduction in progressive and total sperm motility after 4 and 21 hours of incubation when compared with controls. Similarly, peritoneal fluid containing 100 U of TNF alpha/ml did not significantly reduce progressive and total sperm motility after either 4 or 21 hours of incubation; but peritoneal fluid containing 400 U of TNF alpha/ml reduced progressive sperm motility after 4 and 21 hours and total sperm motility after 21 hours of incubation. Peritoneal fluid with a TNF alpha concentration of 800 U/ml caused a significant reduction in both progressive and total sperm motility after 4 and 21 hours when compared with controls of TNF alpha-negative peritoneal fluid. The addition of polyclonal rabbit anti-TNF alpha antibody or 30-min heat inactivation at 56 C of TNF alpha-positive peritoneal fluid reversed the inhibitory effect on sperm motility. The ability of TNF alpha to cause a significant reduction of sperm motility in vitro suggests that this may be a mechanism for the infertility observed in women with minimal endometriosis.