Immunolocalization of aquaporin-9 in rat hepatocytes and Leydig cells

The aquaporin (AQP)-9 gene was recently isolated from human and rat liver cDNA libraries as a member of the water channel family for water and neutral solutes. Although the expression of AQP9 mRNA has been demonstrated in several organs including the liver and testis by Northern blot analysis, the cellular and subcellular localization of the AQP9 protein remains unclear. In the present light and electron microscopic immunohistochemical study, the localization of the AQP9 immunoreactivity was examined in fifteen kinds of rat organs using an antibody against rat AQP9 synthetic peptide. The antibody immunostained a major band of approximately 33 kDa in the liver by Western blot analysis. Immunoreactivity for AQP9 was found exclusively in the liver and testis among the organs examined. In the liver, positive staining appeared selectively along the space of Disse. Immunoelectron microscopy confirmed the localization of AQP9 on the surface of hepatocyte microvilli facing the space of Disse. In the testis, the plasma membrane of Leydig cells located between seminiferous tubules was conspicuously immunoreactive to the antibody. Intense mRNA expression was detected in the liver and testis but not in other organs by ribonuclease protection assay. These findings suggest a specific role for AQP9 in the transport of water and non-charged solutes in hepatocytes and Leydig cells.

L-lactic acid as a mosquito (Diptera: Culicidae) repellent on human and mouse skin

The attraction of Aedes albopictus (Skuse) to hands and forearms of human subjects treated with several concentrations of L-LA solution were studied in a test chamber containing proboscis-amputated mosquitoes. Fewer mosquitoes alighted on L-LA treated human skin than on water-treated control skin. Similar results were found using normal mosquitoes following L-LA and water treatment of mouse skin. The relative repellent effects of L-LA varied with concentration. The minimum repellent concentration was lower than previously reported for human skin. The number of alightments decreased at increasing concentrations of L-LA, demonstrating the absolute repellency of L-LA. Unlike previous reports suggesting that L-LA attracted mosquitoes, our studies using human and mouse skin showed that L-LA exhibited both relative and absolute repellency.

Septic arthritis of the hip associated with atopic dermatitis. A case report

We report a case of septic arthritis of the hip associated with atopic dermatitis. A 15-year female felt a pain in the right hip with unknown cause on May 11, 1998. The pain subsequently became aggravated, and she was admitted to our hospital on May 18. She has had atopic dermatitis since 4 years of age. She showed generalized dermatitis with desquamation and numerous scratch marks. A culture of both skin and joint fluid revealed Staphylococcus aureus. Physical examination revealed tenderness in Scarpa triangle and restricted range of motion. Immunological serology showed an increase in eosinophils and immunoglobulin E, and a decreased reaction of lymphocyte blastoid transformation. Computed tomography (CT) and MRI showed a joint effusion in the right hip. She was diagnosed as having septic arthritis of the hip. Intravenous drip of Cefazolin of 2g was started on the first day of hospitalization and joint irrigation was done on the second day. CRP became negative at 4 weeks, but joint effusion was shown on CT. Additional joint irrigation with Amicamycin (200 mg) was done. As the joint fluid culture became negative, range of motion exercises were started at 6 weeks. She was discharged with a long-leg brace applied at 8 weeks. At 13 months after onset, she had complete relief of the pain and normal activities of daily living. No destructive changes in the hip were found on X-ray examination or MRI. In the present case, an abnormal immune system associated with atopic dermatitis as well as the habit of scratching eruptions may have led to hematogenous spread of skin infection, and caused septic arthritis of the hip.

Transient osteoporosis of the hip during pregnancy

We report the clinical features of and MRI findings in transient osteoporosis of the hip during pregnancy. The study population consisted of 4 patients with a mean age of 33 years. The mean gestational age at onset was 31 weeks (range: 27 to 35 weeks). The main symptoms consisted of a weight-bearing pain in the hip and gait disturbance. The pain occurred suddenly and was of unknown cause and became severe within 2 to 3 weeks. X-ray examinations showed diffuse osteoporosis in the femoral head and neck. Moreover in 3 patients, similar lesions were also found in the lumbar spine or the knee. MRI obtained from 3 patients revealed a mottled low-signal lesion extending from the femoral head and neck on T1-weighted images and a high-signal lesion in the bone marrow suggesting edema on T2-weighted images. Mild elevation of C- reactive protein was shown in 2 patients. Conservative treatments with the limitation of weight bearing and bed rest were performed for all patients, and nonsteroidal anti-inflammatory drugs were given to 3 patients. The hip pain began to decline from 8 to 14 weeks after the onset, and completely disappeared from 14 to 24 weeks. X-ray examinations showed that osteoporotic lesions tended to improve at 10 to 14 weeks, on MRI, a high-signal lesion suggesting bone marrow edema resolved together with relief of the pain. No recurrence was found in any patients at mean follow-up of 70.8 months.

Enterococcal bactibilia in patients with malignant biliary obstruction

Biliary obstruction due to pancreaticobiliary malignancy is often accompanied by bactibilia. The aims of this study were to clarify the impact of preoperative antibiotic use on bile bacterial flora and to identify the bile bacteria responsible for postoperative septic complications in patients with malignant biliary obstruction. Eighty-four patients with malignant biliary obstruction underwent a biliary decompression procedure before definitive surgery. In 63 patients (75%), preoperative bile culture was positive, with nine species being detected. Only the incidence of enterococcal bactibilia increased after antibiotic use (P = 0.0009), with a 16% incidence before and 63% after antibiotic use. When analyzing the correlation between preoperative bile bacteria and postoperative complications, only the Enterococcus species was associated with the occurrence of complications (P = 0.037). In conclusion, bile bacterial flora changes after preoperative antibiotic use, with a significant increase in the incidence of enterococcal bactibilia. The Enterococcus species is most responsible for postoperative septic complications in patients with malignant biliary obstruction.

Radiographic evaluation of the Hill-Sachs lesion in patients with recurrent anterior shoulder instability

The Hill-Sachs lesion is an important bony sign of previous anterior shoulder dislocation and instability. Using orthographic projection, we evaluated the Hill-Sachs lesion in 30 shoulders in 27 patients with recurrent anterior shoulder instability. This produced a clear and undistorted view of the posterolateral notch. For orthographic imaging, the patient was placed supine with the arm in 135 degrees of flexion and 15 degrees of internal rotation. The x-ray beam was angled vertically through the humeral head. The width and depth of the posterolateral notches were measured on the orthographic radiographs. The average posterolateral notch depths were 3.9 +/- 0.9 mm in the dislocation group and 2.1 +/- 1.0 mm in the subluxation group. A shallow Hill-Sachs lesion was indicative of a greater degree of anterior instability of the shoulder.

Low calcium environment effects osteoprotegerin ligand/osteoclast differentiation factor

In coculture with osteoblastic cell line MC3T3-E1 (E1) and mouse bone marrow cells, we reported that numbers of osteoclasts rose significantly on exposure to a low-calcium environment. Here we examined how osteoblasts influence osteoclastogenesis under a low-calcium environment. Comparing low extracellular calcium with a regular calcium environment, osteoprotegerin ligand (OPGL)/osteoclast differentiation factor (ODF) mRNA expression show more increase in the culture of low-calcium environment than in that of a regular calcium environment. Calcium-sensing receptor (CaSR), which was supposed as one of the mechanisms of recognizing extracellular calcium, existedon the surface of E1 cells. When E1 cells stimulated with agonists of CaSR, gadolinium, and neomycin, OPGL/ODF mRNA expression decreased. Moreover, these agonists reduced osteoclast formation in coculture. Taken together, it is possible that osteoblasts may recognize extracellular calcium via CaSR and regulate osteoclastogenesis.

Rapidly turned over protein maintains metabotropic synaptic transmission in Purkinje cells

It has generally been thought that protein synthesis is required for relatively slow cellular processes such as synaptogenesis and synaptic plasticity. In this study on rat cerebellar slices, we found that metabotropic glutamate receptor-mediated synaptic transmission to cerebellar Purkinje cells was quickly and persistently depressed by brief (5 min) applications of translational inhibitors, which were confirmed to induce quick and persistent depression of protein synthesis in cerebellar tissues. Brief applications of transcriptional inhibitors also depressed metabotropic synaptic transmission, but progressively over 1 h, presumably due to depletion of mRNAs in the dendrites. Results of this study indicate the presence of a unique protein(s) that is dynamically involved in metabotropic synaptic transmission.

Spontaneous remission in acute type adult T-cell leukemia/lymphoma

Adult T-cell leukemia/lymphoma (ATL) is a neoplastic disorder of T lymphocytes associated with human T lymphotropic virus type I (HTLV-I). The prognosis of ATL is generally poor. We present here a 79-year-old woman with spontaneous remission of acute type ATL. Spontaneous remission was preceded by surgical biopsy and pneumonia and lasted for two years until she died with pancreas cancer. Monoclonal integration of HTLV-I provirus DNA became undetectable after remission.

Importance of protein kinase C targeting for the phosphorylation of its substrate, myristoylated alanine-rich C-kinase substrate

We visualized the translocation of myristoylated alanine-rich protein kinase C substrate (MARCKS) in living Chinese hamster ovary-K1 cells using MARCKS tagged to green fluorescent protein (MARCKS-GFP). MARCKS-GFP was rapidly translocated from the plasma membrane to the cytoplasm after the treatment with phorbol ester, which translocates protein kinase C (PKC) to the plasma membrane. In contrast, PKC activation by hydrogen peroxide, which was not accompanied by PKC translocation, did not alter the intracellular localization of MARCKS-GFP. Non-myristoylated mutant of MARCKS-GFP was distributed throughout the cytoplasm, including the nucleoplasm, and was not translocated by phorbol ester or by hydrogen peroxide. Phosphorylation of wild-type MARCKS-GFP was observed in cells treated with phorbol ester but not with hydrogen peroxide, whereas non-myristoylated mutant of MARCKS-GFP was phosphorylated in cells treated with hydrogen peroxide but not with phorbol ester. Phosphorylation of both MARCKS-GFPs reduced the amount of F-actin. These findings revealed that PKC targeting to the plasma membrane is required for the phosphorylation of membrane-associated MARCKS and that a mutant MARCKS existing in the cytoplasm can be phosphorylated by PKC activated in the cytoplasm without translocation but not by PKC targeted to the membrane.

Subtype-specific translocation of diacylglycerol kinase alpha and gamma and its correlation with protein kinase C

We examined the translocation of diacylglycerol kinase (DGK) alpha and gamma fused with green fluorescent protein in living Chinese hamster ovary K1 cells (CHO-K1) and investigated temporal and spatial correlations between DGK and protein kinase C (PKC) when both kinases are overexpressed. DGKalpha and gamma were present throughout the cytoplasm of CHO-K1 cells. Tetradecanoylphorbol 13-acetate (TPA) induced irreversible translocation of DGKgamma, but not DGKalpha, from the cytoplasm to the plasma membrane. The (TPA)-induced translocation of DGKgamma was inhibited by the mutation of C1A but not C1B domain of DGKgamma and was not inhibited by staurosporine. Arachidonic acid induced reversible translocation of DGKgamma from the cytoplasm to the plasma membrane, whereas DGKalpha showed irreversible translocation to the plasma membrane and the Golgi network. Purinergic stimulation induced reversible translocation of both DGKgamma and alpha to the plasma membrane. The timing of the ATP-induced translocation of DGKgamma roughly coincided with that of PKCgamma re-translocation from the membrane to the cytoplasm. Furthermore, re-translocation of PKCgamma was obviously hastened by co-expression with DGKgamma and was blocked by an inhibitor of DGK (R59022). These results indicate that DGK shows subtype-specific translocation depending on extracellular signals and suggest that PKC and DGK are orchestrated temporally and spatially in the signal transduction.

Temperature tolerance of the diamondback moth, Plutella xylostella (Lepidoptera: Yponomeutidae) in tropical and temperate regions of Asia

Temperature tolerance was investigated in nine populations of Plutella xylostella Linnaeus from tropical and temperate regions of Asia. At all rearing temperatures between 15 and 35 degrees C, no clear differences were observed in female egg production or larval development between tropical and temperate populations. Thus, tropical populations did not show a high-temperature tolerance superior to that of the temperate populations. In all populations, the net reproductive rate (number of new females born per female) largely depended on the number of eggs laid per female, and egg production significantly decreased with increasing temperature (P < 0.001). Larval developmental rate also showed a significant positive correlation with temperature (P < 0.001). Per cent hatch of eggs and larval survival did not show a significant correlation with temperature: hatching was constant between 15 and 32.5 degrees C, but considerably lower at 35 degrees C. Larval survival was similar between 15 and 30 degrees C, appreciably lower at 32.5 degrees C and declined to 0% at 35 degrees C. Based on these results, environmental conditions under which P. xylostella can maintain a high population density throughout the year in tropical and subtropical regions are discussed.

A case report of insufficiency fracture of the Fossa acetabuli in a patient with rheumatoid arthritis

Aside from vertebral compression fractures, the most common site of insufficiency fractures is the pelvis and lower extremities. In the pelvis, the fractures usually occur in the ilium, the pubis and the ischium, but rarely in the fossa acetabuli. We report a severe insufficiency fracture of the fossa acetabuli in a 78-year-old woman with rheumatoid arthritis (RA). She had associated insufficiency fractures of the rib, the thoracic spine and the sacrum. In our case, senile osteoporosis was present before the onset of the fracture was recognized on radiographs, and RA and corticosteroid therapy might have further aggravated the porosis, resulting in the destruction of the fossa acetabuli. Regarding treatment for the fracture, a cemented total hip replacement without bone graft was attempted for several reasons such as the patient's activities, postoperative rehabilitation and the bone mass of the acetabulum. The postoperative course was satisfactory during study period. However, further follow-up is needed to monitor carefully how the patient will be in the future.

Multiple fish vertebra deformity in child with systemic lupus erythematosus: a case report

We report an 11-year-old female patient with multiple fish vertebra deformity, which occurred in the course of treatment with corticosteroids for systemic lupus erythematosus (SLE). She was treated for SLE with predonisolone (30 mg per day) from April 2, 1996, and presented at our outpatient clinic for an osteoporosis check-up on April 27. She was 132 cm tall with-1.7 standard deviation of the average height, and X-ray examination revealed no evidence of osteoporosis in the spine. Bone mineral density (BMD) was 74.7% of the average BMD. Subsequently, she grew to 136 cm in September. However she began to have low back pain (LBP) from November, and received alfacalcidol. LBP deteriorated after pulse therapy with methylpredonisolone. In June 1997, X-ray examination revealed multiple fish vertebra deformity with 58.3% of the average BMD. Moreover her height had decreased to 131cm. She underwent combination therapy with elcatonin and alfacalcidol. In September 1999, she had no LBP nor progression of fish vertebra deformity. However she had no growth in height. Corticoseroids and SLE have multiple effects on bone metabolism, making the treatment of porosis complicated and difficult.

Acute acalculous cholecystitis after cardiovascular surgery

The development of acute acalculous cholecystitis (AAC) after cardiovascular surgery is an infrequent but devastating complication, the etiology and management of which remains controversial. To evaluate the etiology, treatment, and outcome of patients with AAC, the cases of six patients encountered within an 8-year period who developed AAC after cardiovascular surgery requiring cardiopulmonary bypass (CPB) were reviewed. Atherosclerotic risk factors including diabetes, hyperlipidemia, and smoking were evident in five patients, three of whom had a history of stroke or arteriosclerosis obliterans, while low cardiac output was recognized in three. Percutaneous transhepatic cholecystostomy was performed in five patients, and another required cholecystectomy for peritonitis due to gangrene of the gallbladder. Two patients died of respiratory failure and sepsis after 15 and 82 days of percutaneous drainage, respectively; however, the four survivors had an excellent outcome without any biliary tract disease during a mean follow-up period of 5.3 years. In conclusion, AAC after cardiovascular surgery may result from hypoperfusion of the gallbladder due to various factors including CPB, visceral atherosclerosis, and low cardiac output. We advocate early percutaneous cholecystostomy for patients without peritonitis, while early cholecystectomy is indicated for those with peritonitis.

Osteoblast maturation suppressed osteoclastogenesis in coculture with bone marrow cells

The analysis of co-culture system using osteoblast and bone marrow indicated that the mineralized osteoblast decreased osteoclast formation. This finding was an incentive to better investigate the relation of osteoblast development and osteoclastogenesis. The expression of osteoclast differentiation factor (ODF/RANKL) mRNA and protein dramatically decreased. Alternatively, macropharge colony stimulation factor (M-CSF/CSF-1) transcription and protein secreted in media slightly decreased as the development of osteoblast. On the other hands, mRNA expression and the secretion to the culture medium of osteoclastogenesis inhibitory factor (OPG/OCIF) didn't significantly change depending on osteoblast differentiation. We conclude that osteoblast development might suppress osteoclastogenesis especially with the decrease of ODF/RANKL.

Long-term responders without eradication of hepatitis C virus after interferon therapy: characterization of clinical profiles and incidence of hepatocellular carcinoma

AIMS/BACKGROUND

The aim of this study was to determine the characteristics of patients with chronic hepatitis C showing long-term normalization of alanine aminotransferase (ALT) without eradication of HCV RNA, as well as to investigate the incidence of hepatocellular carcinoma (HCC) in such patients.

METHODS

Four hundred and nineteen patients with histologically-proven chronic hepatitis C who had received interferon (IFN) therapy were studied. Complete response (CR) was defined as persistent normalization of ALT levels with eradication of serum HCV RNA (n= 126). Long-term biochemical response with positive HCV RNA (HCV-positive BR) was defined as a normal ALT level at 6 months after IFN therapy with further persistent normalization of ALT levels for 2 or more years without eradication of serum HCV RNA (n=49). All other patterns were classified as non-response (NR, n=244).

RESULTS

Mean follow-up periods of CR, HCV-positive BR and NR groups were 4.9, 5.2 and 4.9 years, respectively. The HCV-positive BR group had significantly higher serum HCV RNA levels and a higher rate of HCV serological group 1 classification than the CR group. The other characteristics of the HCV-positive BR group were lower histologic activity, lower ALT levels, and a higher rate of females when compared with both the CR and NR groups. Histologic staging in the HCV-positive BR group was significantly lower than that in the NR group. Cumulative incidences of HCC estimated by the Kaplan-Meier method in both the CR and HCV-positive BR groups were significantly lower than those in the NR group (log-rank test, CR vs NR p<0.001, HCV-positive BR vs NR p=0.026).

CONCLUSION

The patients with HCV-positive BR were virologically different from those with CR, and had lower ALT levels and histologic activity when compared to those with CR and NR.

Proboscis amputation facilitates the study of mosquito (Diptera: Culicidae) attractants, repellents, and host preference

Proboscis amputation has facilitated the study of mosquito behavior. Using humans as a host is very important in the study of mosquito attractants, repellents, and host preference. However, mosquito bites cause potential medical problems because of hypersensitivity and perhaps secondary bacterial infection, even using laboratory mosquitoes. Moreover, once a normal female mosquito bites and feeds on human blood, it cannot be used in subsequent probing tests. These problems were resolved by proboscis amputation. Variation of attraction among humans was examined effectively without bites using proboscis-amputated Aedes albopictus Skuse. Proboscis-amputated and normal mosquitoes also showed equal repellency against 1% L-lactic acid. Although the mosquitoes lacked the tip of the labium and some sensilla, they alighted on human forearms in the same way as normal mosquitoes. Because proboscis-amputated mosquitoes continued to probe avidly, they could be used repeatedly, thereby reducing the number of mosquitoes required for experimentation. The use of proboscis-amputated mosquitoes would promote various studies of mosquito attraction or repellency with no risk of hypersensitivity and secondary bacterial infection by mosquito bites.

A case of congenital pseudarthrosis of the tibia treated with pulsing electromagnetic fields. 17-year follow-up

Congenital pseudarthrosis of the tibia presents surgeons with one of the most challenging of all orthopedic problems. Various surgical treatments have succeeded only rarely. We report long-term follow-up of a patient with congenital pseudarthrosis of the tibia treated with pulsed electromagnetic fields (PEMF) and bone grafting. In this severe case, Bassett type III and Boyd type II, encouraging results were achieved with Boyd's dual onlay grafts and PEMF. Seven years after surgery, skeletal maturity was complete and an unacceptable degree of leg shortening had been avoided.

An epidemiologic study of occupational low back pain in truck drivers

The factors in volved in occupational low back pain occurring in professional drivers were investigated epidemiologically with questionnaires (92 items) including low back symptoms, personal factors and occupational factors. The responses of one hundred fifty-three of one hundred eighty-one truck drivers who work in a large chemical industry corporation were analyzed after they had completely filled in questionnaires. As analysis of the results shows, the prevalence of LBP in one month of the survey was 50.3%. Correlating among data of personal factors and LBP, the prevalence of LBP was significantly higher in the drivers (Odd's ratio of 2.7) who answered "yes" to the item "shortage of spending time with family than in the drivers who didnt answer "yes. The occupational factors, working load and working environment showed no correlation with the prevalence of LBP. In contrast, 3 items of the working format related significantly to the prevalence of LBP: "irregular duty time (Odd's ratio of 3.0), "short resting time (2.4), and "long driving time in a day (2.0). Eighty-one of the 153 drivers (52.9%) pointed out the relationship between LBP and work, especially work which muolves vibration or road shock. Our results and the results from previous published studies suggested that vibration is an obvious risk factor for LBP. From the viewpoint of prophylaxis, an improvement in working conditions reduces the incidence of drivers' LBP to some extent.