Usefulness of knee arthroscopy for diagnosis of knee pain in pediatric patients: comparison with preoperative clinical diagnosis

Purpose

To investigate the knee arthroscopic findings of pediatric patients with knee pain.

Subjects

Ninety-five knees of 94 patients (46 males and 48 females) aged 15 years or younger who underwent knee arthroscopy during a 4-year period from January 2007 were studied. The mean age at surgery was 13.5 (7–15) years. The mean interval from symptom onset to arthroscopic examination was 6.8 months (5 days to 2 years 10 months).

Results

The most common cause of knee pain was sports-related activities (64 knees). Other causes included falling from a moving bicycle (5 knees), while knee pain appeared with no defined reason in 14 knees. The most frequent final diagnosis based on knee arthroscopic findings was anterior cruciate ligament (ACL) injury (35 knees), followed by discoid lateral meniscus (16 knees), lateral meniscal tear (11 knees), and medial plica syndrome (9 knees), while no arthroscopic abnormality was observed in 8 of 95 knees. Among the 95 knees, the diagnosis based on preoperative physical tests and imaging findings was different from the arthroscopic diagnosis in 16 knees, 8 of which were diagnosed preoperatively as medial meniscal tear.

Conclusion

ACL injury and discoid lateral meniscus were the predominant conditions in pediatric patients who underwent knee arthroscopic surgery for knee pain. Knee arthroscopy is useful to provide a definitive diagnosis for knee pain in pediatric patients. Preoperative evaluations had a diagnostic accuracy of only 83.2 % and failed to diagnose conditions such as medial plica syndrome and chondral injury. Therefore, diagnosis before knee arthroscopy has to be interpreted with caution.     

Increased insulin sensitivity and hypoinsulinemia in APS knockout mice

A tyrosine kinase adaptor protein containing pleckstrin homology and SH2 domains (APS) is rapidly and strongly tyrosine phosphorylated by insulin receptor kinase upon insulin stimulation. The function of APS in insulin signaling has heretofore remained unknown. APS-deficient (APS(-/-)) mice were used to investigate its function in vivo. The blood glucose-lowering effect of insulin, as assessed by the intraperitoneal insulin tolerance test, was increased in APS(-/-) mice. Plasma insulin levels during fasting and in the intraperitoneal glucose tolerance test were lower in APS(-/-) mice. APS(-/-) mice showed an increase in the whole-body glucose infusion rate as assessed by the hyperinsulinemic-euglycemic clamp test. These findings indicated that APS(-/-) mice exhibited increased sensitivity to insulin. However, overexpression of wild-type or dominant-negative APS in 3T3L1 adipocytes did not affect insulin receptor numbers, phosphorylations of insulin receptor, insulin receptor substrate-1, or Akt and mitogen-activated protein kinase. The glucose uptake and GLUT4 translocation were not affected by insulin stimulation in these cells. Nevertheless, the insulin-stimulated glucose transport in isolated adipocytes of APS(-/-) mice was increased over that of APS(+/+) mice. APS(-/-) mice also showed increased serum levels of leptin and adiponectin, which might explain the increased insulin sensitivity of adipocytes.     

N-terminal deletions of the øX174 external scaffolding protein affect the timing and fidelity of assembly

The first α-helices of Microviridae external scaffolding proteins function as coat protein substrate specificity domains. Mutations in this helix can lengthen the lag phase before progeny production. 5′ deletion genes, encoding N-terminal deletion proteins, were constructed on plasmids and in the øX174 genome. Proteins lacking the first seven amino acids were able to rescue a nullD mutant when expressed from a plasmid. However, the lag phase before progeny production was lengthened. The øX174 mutant with the corresponding genomic gene grew very poorly. The molecular basis of the defective phenotype was complex. External scaffolding protein levels were reduced compared to wild-type and most of the viral coat protein in mutant infected cells appears to be siphoned off the assembly pathway. Second-site suppressors of the growth defects were isolated and appear to act via two different mechanisms. One class of suppressors most likely acts by altering mutant external scaffolding protein expression while the second class of suppressors appears to act on the level of protein-protein interactions.     

The evolution of Epstein-Barr virus inferred from the conservation and mutation of the virus glycoprotein gp350/220 gene

To study variations of Epstein-Barr virus (EBV), we analyzed the gp350/220 gene for several cell lines and Japanese wild isolates using direct sequencing. The N-terminal region was highly conserved in all EBVs except for Jijoye/P3HR-1 and a few isolates. The variation of the region coincided with EBV types A and B (also referred to as types 1 and 2) and were, respectively, designated as the types a and b. The type A/a was detected in most Japanese cell lines and wild isolates, and was classified as China1 type with latent membrane protein (LMP) 1 gene. The type B/b was detected in only a few wild isolates with the Med and China2 types. The C-terminus had more diversity than the N-terminus and lacked the divergence between types A/a and B/b. The phylogenetic analyses of the gp350/220 and LMP1 genes may suggest a mode of EBV evolution into types A/a and B/b and then to LMP1 subtypes.     

Sentinel node biopsy in primary breast cancer: radioactive detection and metastatic disease.

AIM: To examine the relationship between the intensity of the radioactive counts and the presence of tumor metastasis in sentinel lymph nodes (SLNs) in order to correctly identify the number of SLNs to be removed. PATIENTS AND METHODS: Five hundred three breast cancer patients with successful radioisotope localization of SLNs using the combined blue dye and radioisotope method were analyzed. SLN biopsy was continued until all the blue-stained and radioactive nodes were removed. RESULTS: The mean number of harvested SLNs was 1.7+/-0.9, and the number of radioactive SLNs among the harvested nodes was 1.6+/-0.8. SLN metastasis was found in 123 of the 503 cases. The metastasis was detected in the SLN with the highest radioactive count (the hottest SLN) in 94 of the 123 cases with positive SLNs. The positive rate in the hottest SLN was 89% in 61 cases with a single radioactive SLN, and 65% in 62 cases with multiple radioactive SLNs. Of the 29 cases with positivity in other than the hottest SLNs, the metastasis was detected in the second hottest SLN in 16 cases, in the third hottest SLN in one case, in a mixture of negative radioactive SLNs and blue-dye-stained in four cases, and in the negative SLNs and positive non-SLNs (false-negative) in eight cases. Of 123 node-positive cases, 111 cases had metastasis that was detected within the first three hottest SLNs. CONCLUSIONS: These data suggest that lymph node metastasis may not always be detected in the hottest SLN. Thus, in practice, all radioactive and/or blue-dye-stained nodes should be removed for further examination.     

Long-term complete response of multiple hepatic metastases from carcinoma of the papilla of Vater using intrahepatic infusion of 5-FU with low-dose cisplatin following pancreaticoduodenectomy

Of all distant metastases from carcinoma of the papilla of Vater (CPV), the liver is the most frequent site (more than 60%) and should be specifically targeted in the effort to improve the prognosis. However, the optimal chemotherapy regimen for nonresectable liver metastasis has not been clearly established. In this preliminary report, we note a patient with multiple hepatic metastases from CPV successfully treated using intrahepatic infusion of 5-fluorouracil (FU) with low-dose cisplatin. A 62-year-old woman underwent curative pylorus-preserving pancreaticoduodenectomy for CPV. Four months after surgery, followup computed tomography (CT) demonstrated multiple liver metastases. Weekly intrahepatic arterial infusion chemotherapy of 5-FU, 350 mg/m², with low-dose cisplatin (7 mg/m²) was started. Ten months after starting chemotherapy, a complete response was obtained. To date, the patient continues to receive this weekly hepatic arterial infusion chemotherapy without any side effects, and she has successfully maintained a long-term complete response for 20 months. The patient remains well and was able to proceed with daily activity at the last follow up 30 months after starting this chemotherapy regimen. This regimen is safe and effective and is recommended as one of the treatment choices for liver metastases from CPV.