Endoscopic anterior cruciate ligament reconstruction using a computer-assisted fluoroscopic navigation system

Background During anterior cruciate ligament (ACL) reconstruction, placement of the reconstructed ligament affects the clinical results. To accomplish accurate and reproducible placement of the tibial bone tunnel, we employed a fluoroscopic navigation system for endoscopic ACL reconstruction. In this study, preciseness of the tibial tunnel placement was evaluated, and the advantages and disadvantages of this navigation system for endoscopic ACL reconstruction are discussed. Methods Altogether, 16 knees of 16 patients who had undergone ACL reconstruction using this system (navi group) were evaluated regarding the positioning of the tibial tunnel against Blumensaat's line using X-p and the route of the graft by magnetic resonance imaging (MRI). Another 16 knees of 16 patients who underwent endoscopic ACL reconstruction without the navigation system were the controls (control group). Results At the 1-year follow-up, maximally extended lateral knee X-p revealed that the anterior edge of the tibial tunnel and Blumensaat's line were almost aligned and that roof impingement was avoided; the T2-weighted MR images showed that the graft was placed close to and parallel to the intercondylar roof in all the knees of the navi group. The ratio of the distance between Blumensaat's line and the anterior edge of the tibial tunnel at the level of the tibial plateau to the anteroposterior width in fully extended true lateral radiographs was 2.7% ± 3.4% in the navi group and 8.4% ± 7.4% in the control group. Conclusions The computer-assisted fluoroscopic navigation system improves accuracy and decreases dispersion of the tibial tunnel placement against Blumensaat's line in single-bundle ACL reconstruction. This innovative device renders the reconstruction procedure more reliable, eliminating the problem of skeletal variation among patients. However, the function of this navigation system for femoral tunnel placement is insufficient at present. Further refinement of the system is necessary, and the method of application requires improvement.     

Malignant fibrous histiocytoma of the temporal bone with endocranial extension.

Cranial malignant fibrous histiocytomas are rare tumors. Most are hypervascular, destructive masses that are similar to other malignant lesions and to malignant fibrous histiocytomas found elsewhere in the body. We describe a myxoid malignant fibrous histiocytoma of the temporal bone, possibly of dural origin, with features that more closely resembled a meningioma at CT, MR imaging, and angiography.     

Actions of second messengers synthesized by various spasmogenic agents and their relation to mechanical responses in dog tracheal smooth muscle.

1. The effects of the spasmogenic agents, carbachol (CCh), histamine, 5-hydroxytryptamine (5-HT) and 9,11-epithio-11,12-methano-thromboxane A2 (STA2) were investigated on smooth muscle tissues of the dog trachea. 2. CCh (10 microM) produced a larger contraction than high K (128 mM), 10 microM histamine, 5-HT or STA2. Histamine and 5-HT produced the same amplitude of contraction as each other. In Ca-free solution containing 0.2 mM EGTA, only a phasic contraction was evoked by the above agents (except for K which induced no contraction at all). 3. In skinned muscle tissues, the maximum amplitude of contraction that could be induced by Ca (10 microM) was slightly larger than the maximum CCh-induced contraction (also at 10 microM) evoked in intact muscle tissues. Caffeine and inositol 1,4,5-trisphosphate (IP3) both produced contraction. 4. CCh, histamine and 5-HT (10 microM) produced a sustained contraction for over 30 min and also increased phosphorylation of the 20 kD protein of myosin light chain (MLC20) for over 30 min with no attenuation. Greater concentrations of the above agents caused more phosphorylation of MLC20. 5. CCh (above 1 nM), histamine (above 10 nM) and 5-HT (above 100 nM) increased the amount of IP3, in a concentration-dependent manner. Synthesis of IP3 induced by the above agents reached its peak value within 30 s and lasted for about 3 min. The potencies for the synthesis of IP3 were in the following order: CCh greater than histamine greater than 5-HT greater than STA2.(ABSTRACT TRUNCATED AT 250 WORDS)     

A case of ectopic large pituitary adenoma

Ectopic pituitary adenomas are very rare and only 17 cases have been reported. In this paper we present a case of large pituitary adenoma originating in the suprasellar region. A 26-year-old man was admitted to our clinic with a chief complaint of headaches. Neurological examination revealed slight disorientation and bilateral choked disk. Hormonal study revealed that the serum prolactin level was 3300ng/ml and serum growth hormone level was 29.5ng/ml. Computed tomography showed a large mass in the suprasellar region extending upward to the third ventricle and backward to the pons. T1-weighted MR imaging revealed that the intensity of the mass was the same as that of the cerebral cortex and the pituitary gland was showing high intensity in the pituitary fossa. The tumor was radically removed via the transpetrosal transtentorial approach. Histologically, the tumor was a prolactin-growth hormones producing pituitary adenoma. The literature was reviewed and the origin of the tumor was discussed.     

Characterization of htAKR, a novel gene product in the aldo-keto reductase family specifically expressed in human testis

In human testis, expression of a novel member of the aldo-keto reductase family was identified. Based on its testis-specific expression, we termed this protein human testis aldo-keto reductase (htAKR). In addition to four major isoforms, the existence of multiple alternatively spliced products of htAKR was detected using RT-PCR followed by nested PCR. htAKR was a homologue of mouse liver keto-reductase, AKR1E1, with close similarity in their genomic organizations. htAKR4, the longest isoform, was expressed as a non-fused native form. It exhibited a limited activity toward 9,10-phenanthrenequinone, while no activity toward the steroids or prostaglandins was demonstrated. Using the laser capture microdissection technique and RT-PCR, expression of htAKR was detected in testicular germ cells as well as in interstitial cells. The levels of htAKR mRNA in the tissues obtained from seminoma were much lower than those in normal testes. A significant decline in the htAKR expression was observed when NEC8, a cell line originated from a human testicular germ cell tumour, was exposed to phorbol 12-myristate 13-acetate or 5alpha-dihydrotestosterone. These results indicate that the expression of htAKR, down-regulated in the testicular tumour, is possibly controlled by mitogenic and hormonal signals.     

Polysialic acid, a unique glycan that is developmentally regulated by two polysialyltransferases, PST and STX, in the central nervous system: From biosynthesis to function

Polysialic acid is a developmentally regulated carbohydrate composed of a linear homopolymer of a-2,a-linked sialic acid residues. This unique glycan is mainly attached to the neural cell adhesion molecule (N-CAM) and implicated in many morphogenic events of the neural cells by modulating the adhesive property of N-CAM. Recently, the cDNA that encodes polysialyltransferase, which is responsible for the polysialylation of N-CAM, was successfully cloned from three mammalian species. This review focuses on the molecular cloning of human polysialyltransferase, designated PST. it then describes the number of enzymes actually required for the polysialylation of N-CAM using an in vitro polysialyltransferase assay. Comparisons between PST and another polysialyltransferase, sialyltransferase X (STX), are made and it Is demonstrated that both enzymes can independently form polysiatic acid In vitro , but that during neural development they coordinately but distinctly synthesize polysialic acid on N-CAM. The role of polysialic acid in the central nervous system is also discussed. Finally, evidence that the two polysialyltransferases, PST and STX, apparently have distinct roles in the development of neural cells is provided by using a neurite outgrowth assay.     

Helicobacter pylori infection produces expression of a secretory component in gastric mucous cells

Helicobacter pylori infection induces the expression of a secretory component (SC) in gastric epithelial cells. We investigated the cell lineage of the SC- and immunoglobulin (Ig) A-expressing epithelial cells in H. pylori-infected gastric mucosa. Materials were obtained by means of gastric biopsy from H. pylori-infected patients (24 cases) before and after the eradication of H. pylori, from five normal uninfected volunteers, and from three gastrectomy cases. Acetic acid-ethanol-fixed and paraffin-embedded specimens were examined using histochemical staining for gastric mucins (periodic acid oxidation-thionine Schiff reaction-concanavalin A-horse radish peroxidase staining) by means of immunostaining for gastric mucins (45M1 and HIK1083), intestinal cells (MUC2 and CD10), Ki67, H. pylori, SC, and IgA. The SC and IgA were not found in normal gastric mucosa. The expressions of the SC and IgA in gastric surface mucous cells and mucous neck cells in the generating zone of the gastric mucosa of H. pylori-infected patients were significantly higher before eradication of H. pylori than after the eradication. These mucous cells have the potential for SC-mediated translocation of IgA into the gastric lumen, and this may act as part of the antibacterial defense system against H. pylori infection in the gastric generating zone.     

Primary structure,functional characterization and developmental expression of the ascidian Kv4-class potassium channel

Ascidians belong to the primitive chordates and their larvae show symmetrical beating of the tail, which is reminiscent of the swimming pattern in primitive vertebrates. Since ascidian larva contains only a small number of neurons in their entire larval nervous system, they will potentially provide a simple model for the study of animal locomotion. In a step towards the goal of establishing the molecular basis underlying ascidian larval neurophysiology, we describe here a Kv4 class of voltage-gated potassium channel, TuKv4, from Halocynthia roretzi. Whole mount in situ hybridization indicates that TuKv4 is expressed in most of larval neurons including motor neurons. TuKv4-currents reconstituted in Xenopus oocytes show currents with similar properties to the lower-threshold A-type currents from cleavage-arrested ascidian blastomeres of neural lineage. However, the voltage-dependency of the steady-state inactivation and activation was shifted leftward by 20 mV, as compared with native A-type currents, suggesting that other components may be required to restore full function of the Kv4 channel. Unexpectedly, another isoform lacking C-terminal cytoplasmic region was also isolated. This truncated isoform did not lead to a functional current in Xenopus oocytes. RT-PCR analysis showed that the truncated form is transiently expressed during larval development, suggesting some developmental role for potassium channel expression.     

Serum FDP assay with latex photometric immunoassay and its analysis by immunoblotting

Sixty patients' sera with FDP-E value ranged from 200 to 2,500 ng/ml by LPIA system were assayed for FDP-Total (FDP-T) by the same system and FDP-DD by ELISA. Correlations of values between FDP-E, FDP-T and FDP-DD were excellent and ratio of FDP-T/FDP-E (T/E) and FDP-DD/FDP-E (DD/E) from same 60 sera were 32.4 + 7.4 and 1.55 + 0.50, respectively. Ratio of T/E from sera of FDP-E value demonstrating more than 500 ng/ml were classified into three groups, namely, 25.0-35.0, less than 18.0, and more than 50.0. Ten sera in each group were analyzed for FDP fragments of D, DD, Y, DY or X (DY/X) and high molecular weight (HMW) with SDS-PAGE and immunoblot method. It was found that relative concentration and proportion of D and DD.E fragments showed its characteristic pattern in each group.     

Cell lineage specificity of newly raised monoclonal antibodies against gastric mucins in normal, metaplastic, and neoplastic human tissues and their application to pathology diagnosis

The specificity of monoclonal antibodies against gastric mucins (designated as HIK1083, PGM 36, and PGM 37) was studied immunohistochemically in normal, metaplastic, and neoplastic human tissues. These antibodies labeled class III mucin-producing cells identified by paradoxical concanavalin A staining in normal stomach, duodenum (Brunner gland), biliary tract, and main pancreatic duct; in mucinous metaplasia of pancreas and gallbladder; and in adenocarcinomas of stomach (90%), bile duct (80%), gallbladder (100%), pancreas (80%), lung (100% of goblet cell type adenocarcinomas), ovary (67% of mucinous carcinomas), and uterine cervix (100% of adenoma malignum tumors). Normal and neoplastic cells of esophagus, colon, salivary gland, kidney, endometrium, breast, prostate, and liver, as well as normal small intestine, lung, and uterine cervix, were all negative. The antibodies used should be valuable for the detection of class III mucin and class III mucin-producing cells in normal, metaplastic, and neoplastic tissues.