The paired Ig-like receptor PIR-B is an inhibitory receptor that recruits the protein-tyrosine phosphatase SHP-1

An emerging family of cell surface inhibitory receptors is characterized by the presence of intracytoplasmic immunoreceptor tyrosine-based inhibition motifs (ITIM). These ITIM-bearing inhibitory receptors, which are typically paired with activating isoforms, associate with Src homology domain 2-containing phosphatases following ITIM tyrosine phosphorylation. Two categories of phosphatases are recruited by the ITIM-bearing receptors: the protein-tyrosine phosphatases, SHP-1 and SHP-2, and the polyphosphate inositol 5-phosphatase, SHIP. The dynamic equilibrium of B cell activation is partially controlled by two well known ITIM-bearing receptors, CD22 and FcgammaRIIB, a low affinity receptor for IgG. We describe here that a murine ITIM-bearing molecule, PIR-B, can also negatively regulate B cell activation. Tyrosine-phosphorylated ITIMs allow PIR-B to associate with SHP-1 but not with SHIP. Engagement of PIR-B thereby initiates a SHP-1-dependent inhibitory pathway that may play an important role in regulating B lymphocyte activation.

Measurement of prostaglandin E2 and leukotriene B4 in the gingival crevicular fluid

The arachidonic acid metabolites prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) are inflammatory mediators which are likely to be involved in the pathogenesis of periodontal disease. PGE2 mediates vasodilatation, increases vascular permeability, enhances pain perception by bradykinin and histamine, alters connective tissue metabolism and enhances osteoclastic bone resorption. LTB4 causes the accumulation of inflammatory cells in the inflamed sites, and degranulation of polymorphonuclear leukocytes.

OBJECTIVE

To measure gingival crevicular fluid (GCF) levels of PGE2, LTB4 and periodontal health.

METHODS

The periodontal condition of 24 subjects was evaluated on the basis of plaque index, gingival index, probing depth, and attachment level. GCF samples were collected from one or two site(s) of each sextant per subject and the volume was measured using Periotron 6000. Samples were then assayed for PGE2 and LTB4 using a competitive enzyme immunoassay. Mean PGE2 and LTB4 levels were determined for each subject and group means compared.

RESULTS

Significant differences in the levels of PGE2 and LTB4 were found between patients with periodontitis, and non-periodontitis individuals (P < 0.001). The PGE2/LTB4 levels were positively correlated with the clinical parameters (P < 0.01) and reduced markedly after phase 1 of the periodontal treatment (P < 0.01). The total amount and concentration (ng ml-1) of LTB4 was positively correlated with the gingival index (P < 0.01).

CONCLUSIONS

These results indicate that the levels of PGE2 correlated with the severity of the periodontal status, and the levels of LTB4 correlated with gingival inflammation. Thus, our data suggest that the total amounts of PGE2/LTB4 may be good indicators for periodontal inflammation.

A follow-up study of annular pancreas in infants and children

Fifteen pediatric patients undergoing surgery for annular pancreas from 1984 to 1996 were analyzed. Vomiting was the most common presenting symptom. Twelve patients (80%) had associated anomalies including malrotation (40%), intrinsic duodenal obstruction (33%), Down syndrome (27%) and duodenal bands (27%). Their ages at operation were between 5 hours and 8.5 years, with a median of 4 days. Surgical treatment included duodenojejunostomy in nine, duodenoduodenostomy in five and duodenotomy with duodenoplasty in one. The mean duration for reestablishment of bowel transit was 17.9 days, with 22.8 days for duodenojejunostomy and 12.3 days for duodenoduodenostomy. All cases received postoperative follow-up, but only 11 of them were long-term followed until April 1997, with a duration ranging from 1 year and 2 months to 11 years, with a median of 7 years and 5 months. The survival was 100%, but 12 cases (80%) developed postoperative complications including cholestatic jaundice (53%), upper gastrointestinal motility disorder (47%), failure to thrive (40%) and chronic diarrhea (33%). Annular pancreas divisum was noted in one case with chronic relapsing pancreatitis. At the end of follow-up (April 1997), when final ages ranged from 1 year and 2 months to 18 years and 9 months with a median of 7 years and 5 months, there were still problems: steatorrhea in 1, diarrhea after fatty diet in 3, malnutrition in 4, failure to thrive in 3 and lower concentration of stool trypsin in 3 cases. In conclusion, close long-term follow-up is essential for infants treated for annular pancreas because many of them can be expected to develop complications, even if the initial postoperative period is uncomplicated and survival is excellent.

Factors affecting postoperative fecal soiling in Hirschsprung's disease

We retrospectively assessed the factors that may contribute to fecal soiling after surgery for Hirschsprung's disease. Fifty-eight patients underwent surgery for Hirschsprung's disease and returned for follow up. The patients were divided into two groups based on the presence or absence of fecal soiling. The postoperative period, level of bowel pulled through, stool frequency, stool character, presence or absence of anorectal surgical complications, and manometric findings of the two groups were compared. Forty-three patients (40 boys, 3 girls, mean age 9.5 yr) had soiling and 15 (10 boys, 5 girls, mean age 10.2 yr) did not. Patients with soiling had significantly higher rates of anorectal surgical complications (60% vs 7%), abnormal stool character (75% vs 7%), stool frequency greater than three times per day (63% vs 20%), absence of rectoanal inhibitory reflex (33% vs 2%), and narrow anorectal pressure gradient (60% vs 13%) than those without. The results of manometric study suggested that a damaged internal sphincter or irritable neorectum might have contributed to fecal soiling. In conclusion, although anorectal surgical complications might result in both irritable neorectum and damaged internal sphincter, their effect on the neorectum (significantly increased rate of high resting rectal pressure) seemed to outweigh that on the internal sphincter. A competent anal sphincter and a less irritable neorectum after operation may therefore lower the likelihood of fecal soiling.

Bone metastases in patients with gastrinomas: a prospective study of bone scanning, somatostatin receptor scanning, and magnetic resonance image in their detection, frequency, location, and effect of their detection on management

PURPOSE

To determine whether bone scan, magnetic resonance imaging (MRI), or somatostatin receptor scintigraphy (SRS) is best for identifying bone metastases in patients with gastrinomas, as well as their frequency and location, whether their detection affects management, and what patient subgroups should be examined.

MATERIALS AND METHODS

One hundred fifteen patients with gastrinoma were prospectively studied. Patients were examined yearly and those with liver metastases were reexamined every 3 months. Based on clinical history, histology, growth pattern, and development of new bone lesions, possible bone metastases were classified as to whether they were or were not bone metastases. Imaging results were correlated at different times in the disease course and with disease extent.

RESULTS

Bone scan was positive in 52 patients, MRI in seven, and SRS in six. Eight patients (7%) were determined to have bone metastases and MRI was correctly positive in seven, SRS in six, and bone scan in five. SRS or MRI was positive in all patients with bone metastases. Bone scan had significantly lower specificity and sensitivity, and a higher rate (P < .02) of false-negative results than MRI or SRS. Bone metastases occurred in 31% of patients with liver metastases and 0% with only lymph node metastases. The initial bone metastases were in the spine or sacrum (75%) followed in descending order by the pelvis or sacroiliac joints (38%), scapula or shoulder, and ribs. In all cases, detection of bone metastases changed the management.

CONCLUSION

SRS and MRI, because of high sensitivity and specificity, are recommended over bone scanning to screen for bone metastases in patients with gastrinomas. However, because bone metastases can occur initially outside the axial skeleton, SRS is the recommended initial localization method of choice. Bone metastases occur in 7% of all patients and 31% of patients with liver metastases, only occur in patients with liver metastases, are usually in the axial skeleton initially, and their detection changes management in all cases. Patients with pancreatic endocrine tumors with liver metastases should undergo SRS every 6 months to 1 year to detect bone metastases.

Anorectal function and endopelvic dissection in patients with repaired imperforate anus

Fifty-eight patients with anorectal malformations were closely followed up for postoperative anorectal function. Constipation was noted shortly after anorectoplasty in 10 of 28 low anomalies (35.7%) treated with limited sagittal anorectoplasty (LSARP), in 18 of 25 high or intermediate anomalies (72.0%) treated with posterior sagittal anorectoplasty (PSARP), but in none of 5 high or intermediate anomalies treated with Rehbein's mucosa-stripping endorectal pull-through and anterior sagittal perineal anorectoplasty (R-ASAP). The constipation resolved mostly within 1-2 years after repair under conservative management, but persisted beyond 2 years after repair in 3/25 children with LSARP and 10/25 with PSARP. Anal soiling was noted in 1/23 (4.3%) LSARP and 6/22 (27.3%) PSARP patients, but normal anorectal function was attained in 20/23 LSARP (86.9%) and 11/12 PSARP patients (50.0%) by the time of toilet training. Manometric studies disclosed that the resting rectal pressure (RRP) was lower and the anorectal pressure gradient (ARPG) higher in the constipated than the non-constipated children, while the RRP was higher and the ARPG lower in the soiled than the non-soiled patients. The ARPG after R-ASPA was close to that of non-constipated and in between that of the constipated and soiled patients. The rectoanal sphincter inhibitory reflex was not related to defecation status or surgical procedures, but showed a tendency toward positive conversion with time or after exclusion of esctatic terminal bowel in the severely constipated. It is concluded that anorectal function in patients with repaired imperforate anus seems to be more affected by the extent of endopelvic dissection than by preservation of the terminal bowel or sphincter muscles.

Six New Diarylbutane Lignans from Justicia procumbens

Six new diarylbutane lignans, namely, justin A (1), (-)-dihydroclusin diacetate (2), secoisolariciresinol dimethyl ether diacetate (3), 5-methoxy-4,4'-di-O-methylsecolariciresinol diacetate (4), justin B (5), and justin C (6), together with three known diarylbutane lignans [2,3-demethoxysecisolintetralin acetate (7), secoisolariciresinol dimethyl ether (8), and 5-methoxy-4,4'-di-O-methylsecolariciresinol (9)], were isolated from the whole plant of Justicia procumbens. Their structures were established by spectral analysis.

In situ detection of Epstein-Barr virus in breast cancer

Epstein-Barr virus (EBV) is strongly associated with nasopharyngeal carcinoma and some lymphoepithelioma-like carcinomas from other anatomic sites. This study investigates the presence of EBV in breast cancer. Immunohistochemistry for EBV proteins (EBV nuclear antigen-2 and latent membrane protein-1) and in situ hybridization for EBV-encoded small nuclear RNAs (EBER-1 and -2) were performed in 60 invasive breast cancers. None of the 60 breast cancer samples showed detectable EBV. These results suggest that EBV may not play a significant role in the etiology of breast cancers in Taiwan.

Visualization of fibrous dysplasia during somatostatin receptor scintigraphy

Somatostatin receptor scintigraphy was performed on a patient with McCune-Albright syndrome and acromegaly. No evidence of pituitary disease was found, but uptake of (111)In-pentetreotide was noted in areas of fibrous dysplasia. This uptake was not changed after 6 mo of octreotide therapy. The patient's bone disease also remained stable. The possible implications of these findings are discussed.

Gingival crevicular fluid lactoferrin levels in adult periodontitis patients

The present study was designed to determine in a cross-sectional study whether there was any relationship between the levels of lactoferrin in gingival crevicular fluid and clinical periodontal parameters. Crevicular fluid was collected from individual sites using standardized filter paper strips (clinically healthy sites, N = 23; periodontitis sites, n = 66) and evaluated for lactoferrin by enzyme-linked immunosorbent assay. The data showed that: (1) the total amounts of lactoferrin were 0.003-0.021 ng (30 second sample) (average 0.009 +/- 0.005 ng) in a clinically healthy periodontium group and 0.016-3.847 ng (30 second sample) (average 0.575 +/- 0.069 ng) in adult periodontitis patients (statistically significantly higher in adult periodontitis patients); and (2) the total amounts of lactoferrin were significantly correlated with clinical parameters, especially a strong positive correlation with gingival crevicular fluid volume (r = 0.85, p < 0.01) and with probing depth (r = 0.71, p < 0.01). These results indicated that quantification of lactoferrin in gingival crevicular fluid may be a more sensitive indicator of periodontal pathology than traditional clinical indices.

Severe colonic complications in acute pancreatitis

BACKGROUND

Colonic complications in patients with acute pancreatitis may be very severe and have rarely been analyzed in Chinese patients.

METHODS

We retrospectively evaluated 1,637 patients with acute pancreatitis who were admitted to the Veterans General Hospital-Taipei from January 1986 to December 1995 in order to identify those with severe colonic complications. The clinical, radiologic and pathologic features and surgical findings in these patients are reviewed.

RESULTS

Eight of 1,637 patients with acute pancreatitis had severe colonic complications. Six of them were diagnosed between two and eight weeks after the onset of clinical pancreatitis. All had a Ranson's score of at least 3. Four patients, including one with hematochezia, had a strong positive reaction for occult blood in stool specimens. Computed tomography (CT) revealed necrotizing pancreatitis and colonic wall swelling in all eight patients. Colonic involvement was discovered by CT in two patients prior to surgery, one with colocutancous fistula and the other with colonic perforation. The other six patients were found to have colonic involvement incidentally at the time of laparotomy. All of the colonic involvements were located near the splenic flexure. In addition to necrosectomy, three patients underwent segmental hemicolectomy and the remaining five patients had simple closure of the perforation. Diverting loop ileostomy or colostomy was also carried out in all patients. Three patients (34%) died of overwhelming sepsis superimposed on the subsequent multiple organ failure between 44 and 122 days after the onset of pancreatitis.

CONCLUSIONS

Severe colonic complications of acute pancreatitis are rare. Although preoperative diagnosis is difficult, CT may be helpful to make an early diagnosis. These complications should be suspected in patients with severe acute pancreatitis when acute lower gastrointestinal hemorrhage or positive stool occult blood is found two to eight weeks after the onset of pancreatitis or when CT reveals necrotizing pancreatitis and colonic wall swelling; this will allow early surgical intervention.

Molecular cloning, characterization and tissue expression of prophenoloxidase cDNA from the mosquito Armigeres subalbatus inoculated with Dirofilaria immitis microfilariae

A cDNA encoding mosquito Armigeres subalbatus prophenol oxidase (As-pro-PO) was obtained by rapid amplification of cDNA ends-polymerase chain reaction (RACE-PCR) after Dirofilaria immitis inoculation. The 2205 bp As-pro-PO cDNA contains a 32 bp 5'-noncoding region, a 2055 bp open reading frame (685 amino acids), and a 118 bp 3'-noncoding region. Hydrophobic signal peptide for the endoplasmic reticulum targeting is not found in the NH2-terminal region. Two potential copper-binding domains, amino acids 197-245 and 345-412, are highly homologous to those of the other insect pro-POs. A 2.2 kb As-pro-PO transcript was identified by Northern blot analysis using D. immitis microfilariae-inoculated A. subalbatus. Both in situ hybridization and Northern blot analysis demonstrated that As-pro-PO mRNA was synthesized in mosquito haemocytes but not in other tissues, i.e. fat bodies, midguts and ovaries, etc.

Ultrastructural studies on the reproductive system of male Aedes aegypti (Diptera: Culicidae) infected with dengue 2 virus

Dengue 2 virus was found by transmission electron microscopy to be present in the reproductive tissues of male Aedes aegypti (L) 14 d after intrathoracic inoculation. Dengue 2 particles were detected in the matrix, epithelial cells, and the peripheral fat body of the testes; secretory droplets of columnar cells of the accessory glands; and the epithelial and muscle cells of the seminal vesicles. However, none was found in the germ cells (i.e., spermatogonia, spermatocytes, spermatid, or spermatozoa). These observations indicate that fluid transfer may be the mechanism of venereal transmission of dengue 2 virus by Ae. aegypti.

Mutations in microphthalmia, the mouse homolog of the human deafness gene MITF, affect neuroepithelial and neural crest-derived melanocytes differently

The mouse microphthalmia (Mitf) gene encodes a basic-helix-loop-helix-zipper transcription factor whose mutations are associated with abnormalities in neuroepithelial and neural crest-derived melanocytes. In wild type embryos, Mitf expression in neuropithelium and neural crest precedes that of the melanoblast marker Dct, is then co-expressed with Dct, and gradually fades away except in cells in hair follicles. In embryos with severe Mitf mutations, neural crest-derived Mitf-expressing cells are rare, lack Dct expression, and soon become undetectable. In contrast, the neuroepithelial-derived Mitf-expressing cells of the retinal pigment layer are retained, express Dct, but not the melanogenic enzyme genes tyrosinase and Tyrp1, and remain unpigmented. The results show that melanocyte development critically depends on functional Mitf and that Mitf mutations affect the neural crest and the neuroepithelium in different ways.

Pyogenic liver abscess complicating a ventriculoperitoneal shunt

Pyogenic liver abscess is a rare complication of ventriculoperitoneal (VP) shunting. We report a 4-month-old female with this complication who was successfully treat ed by computed tomography-guided percutaneous transhepatic catheter drainage, shunt externalization, and parenteral antibiotics. Liver abscess is a possible intra-abdominal complication of VP shunting, and imaging studies are good adjuncts in making the clinical diagnosis.

Effects of high dose octreotide on retrograde bile salt-induced pancreatitis in rats

The effects of somatostatin and octreotide (a long acting somatostatin analogue) in acute pancreatitis are inconclusive. This study examined the prophylactic and therapeutic effects of different doses of octreotide on retrograde sodium taurodeoxycholate-induced acute necrotizing pancreatitis in rats. The rats were divided into 4 groups receiving subcutaneous injection of saline, octreotide 10 microg/kg, 20 microg/kg at 0, 8 and 16 h and octreotide 20 microg/kg at 5, 13 and 21 h, separately. The serum levels of amylase and lipase, pancreatic histopathology, mortality and hemodynamics were examined. Octreotide significantly reduced serum levels of amylase and lipase at 12 h and the degree of pancreatic edema, necrosis and hemorrhage at 18-24 h as compared to the control group. Prophylactic octreotide 10 microg/kg significantly decreased the 24-h mortality from 100% to 44.4% (p < 0.05). The 24-h mortality further reduced to 12.5% and 10% with prophylactic and therapeutic octreotide 20 microg/kg, respectively. The decrease of mean arterial pressure at 12 h was significantly lower in octreotide groups than in the control group. We conclude that octreotide improves pancreatic histopathology and survival in acute necrotizing pancreatitis in rats.

Characterization of a Potyvirus Causing Mild Mosaic on Tuberose

A virus inducing mild mosaic symptoms on the leaves and peduncles of tuberose (Polianthes tuberosa) was isolated and partially characterized. The isolate, designated Tbr1, could be transmitted mechanically and by green peach aphids (Myzus persicae) in a non-persistent manner to tuberose seedlings but not to 16 common assay species. Flexuous rod-shaped particles with a mean length of 750 nm could be easily seen in infected leaf dips and in purified samples. Cytoplasmic cylindrical inclusions, pinwheel and laminated aggregates similar to those assigned to potyviral cylindrical inclusion type II, were observed in infected tuberose leaves. The purified capsid contained a single species of protein monomer with an estimated relative mass of 38 kDa. In reciprocal sodium dodecyl sulfate-immunodiffusion tests, antiserum against Tbr1 reacted only with its homologous antigen but not with 22 different known potyviruses. Using primer pairs designed for potyvirus sequence amplification, a 2-kb DNA product equivalent to the estimated size for potyviruses was consistently amplified from purified Tbr1 virions or from crude infected tissue by reverse transcription polymerase chain reaction. On the basis of these results, Tbr1 was recognized as a unique species in the genus Potyvirus and hence designated as tuberose mild mosaic potyvirus (TMMV).

Antisense oligonucleotides against rat brain alpha1E DNA and its atrial homologue decrease T-type calcium current in atrial myocytes

Low voltage-activated, or T-type, calcium currents are important regulators of neuronal and muscle excitability, secretion, and possibly cell growth and differentiation. The gene (or genes) coding for the pore-forming subunit of low voltage-activated channel proteins has not been unequivocally identified. We have used reverse transcription-PCR to identify partial clones from rat atrial myocytes that share high homology with a member of the E class of calcium channel genes. Antisense oligonucleotides targeting one of these partial clones (raE1) specifically block the increase in T-current density that normally results when atrial myocytes are treated with insulin-like growth factor 1 (IGF-1). Antisense oligonucleotides targeting portions of the neuronal rat alpha1E sequence, which are not part of the clones detected in atrial tissue, also block the IGF-1-induced increase in T-current, suggesting that the high homology to alpha1E seen in the partial clone may be present in the complete atrial sequence. The basal T-current expressed in these cells is also blocked by antisense oligonucleotides, which is consistent with the notion that IGF-1 up-regulates the same gene that encodes the basal current. These results support the hypothesis that a member of the E class of calcium channel genes encodes a low voltage-activated calcium channel in atrial myocytes.

Reversed arterial flow in free flap surgery for leg reconstruction

A lower leg open fracture with an accompanying extensive soft-tissue defect may require free flap transfer to resurface the wound. In open-leg fracture injuries the major arteries are frequently damaged during the injurious event. When the antegrade arterial blood flow is not available for arterial inflow to the free flap, end-to-side arterial anastomoses or a venous graft from a proximal healthy artery is an appropriate solution. Reversed arterial flow is another technique that may be used to provide arterial inflow to the free flap. We report 5 patients with open tibial fracture injuries that were successfully covered using latissimus dorsi muscle free flaps with reverse arterial inflow and either antegrade venous outflow (4 patients) or retrograde outflow (1 patient). This technique is indicated when (1) the defect is not located at the site adjacent to the residual antegrade artery, (2) a long vein graft might pass through severely scarred soft tissue, or (3) after failure in end-to-side anastomosis with accompanying insufficient antegrade proximal arterial flow but good distal arterial reflux.

Comparison of various methods of detection of different forms of dengue virus type 2 RNA in cultured cells

In this report, the sensitivity of various methods of detection of dengue virus type 2 (DEN-2) sense, antisense, replicative intermediate (RI) and replicative form (RF) RNAs in infected mosquito Aedes pseudoscutellaris AP-61 and mammalian baby hamster kidney BHK-21 cells is compared. LiCl precipitation was used for separation of viral RF RNA from RI RNA. Our results show that reverse transcription-polymerase chain reaction (RT-PCR) followed by Southern blot analysis and slot blot hybridisation of LiCl-fractionated RNA were the most sensitive methods of detection of viral RNA and determination of its single-stranded form. Northern blot analysis was the least sensitive method of detection of any form of viral RNA. Using slot blot hybridisation of LiCl-precipitated RNA, viral RI RNA containing de novo synthesised negative strand viral RNA was first detected 30 mins after virus inoculation in both cell lines. This is the earliest time of detection of DEN viral RNA synthesis in host cells so far reported. However, RF RNA could not be detected until 24 hrs post infection (p.i) in AP-61 and 2 days p.i. in BHK-21 cells, respectively. The sequential order of individual forms of viral RNA detected in the infected cells was RI, RF and genomic RNAs. Viral RNA was detected in AP-61 cells always earlier than in BHK-21 cells. Moreover, the level of viral RNA in AP-61 cells was higher than that in BHK-21 cells, suggesting that the virus replicated more actively in AP-61 cells. In conclusion, the LiCl separation of viral RNA followed by slot blot hybridisation was found to be the most sensitive and reliable method of detection of DEN virus RI, RF and genomic RNAs in the infected cells. Moreover, this method can be applied to determine the replication status of any single-stranded RNA virus in the host.

Two tandemly repeated telomere-associated sequences in Nicotiana plumbaginifolia

Two tandemly repeated telomere-associated sequences, NP3R and NP4R, have been isolated from Nicotiana plumbaginifolia. The length of a repeating unit for NP3R and NP4R is 165 and 180 nucleotides respectively. The abundance of NP3R, NP4R and telomeric repeats is, respectively, 8.4 x 10(4), 6 x 10(3) and 1.5 x 10(6) copies per haploid genome of N. plumbaginifolia. Fluorescence in situ hybridization revealed that NP3R is located at the ends and/or in interstitial regions of all 10 chromosomes and NP4R on the terminal regions of three chromosomes in the haploid genome of N. plumbaginifolia. Sequence homology search revealed that not only are NP3R and NP4R homologous to HRS60 and GRS, respectively, two tandem repeats isolated from N. tabacum, but that NP3R and NP4R are also related to each other, suggesting that they originated from a common ancestral sequence. The role of these repeated sequences in chromosome healing is discussed based on the observation that two to three copies of a telomere-similar sequence were present in each repeating unit of NP3R and NP4R.

Leptomeningeal malignant melanoma arising in neurocutaneous melanocytosis: a case report

A rare case of histology-proved giant congenital melanocytic nevus (GCMN) with symptomatic leptomeningeal melanocytosis is reported. A 26-year-old man had had a large patch of pigmented nevus over his back and left arm since birth. He had begun to have seizures as well as symptoms and signs of increased intracranial pressure about six months before admission. Serial computed tomography of brain showed hydrocephalus, diffuse leptomeningeal enhancement and multiple well-enhanced, rapid-growing nodules on the surface of the cerebellum and left parietal lobe. Magnetic resonance imaging (MRI) revealed T1 shortening of leptomeninges on precontrast T1 weighted imaging. Skin biopsy was done twice and showed intradermal nevus. Biopsy on one of the intracranial nodules revealed malignant melanoma arising in the melanocytosis. He died one year after the onset of neurologic symptoms. For early diagnosis of neurocutaneous melanocytosis, we suggest 1) MRI, and 2) leptomeningeal biopsy in patients with suspected leptomeningeal malignant melanoma.

Alcohol problems and long-term psychosocial outcome in Chinese patients with bipolar disorder

BACKGROUND

A high comorbidity of alcohol use disorders among Western bipolar patients is recognized and worsens the outcome of bipolar illness. In view of lower prevalence of alcohol use disorders in some Asian groups, we attempted to investigate the alcohol problems among Chinese bipolar patients in Taiwan.

METHODS

The clinical data of bipolar patients (DSM-III-R) having been followed-up naturally for at least 15 years were obtained by a combination of chart reviews and interviews with patients and family members.

RESULTS

Based on a retrospective chart review of 158 patients, 8.2% of them were found to have alcohol problems. The lifetime prevalence of alcohol abuse was 6.9%, and of alcohol dependence 3.0% among 101 subjects accepting interview. According to the Global Assessment of Functioning Scale (APA, 1994) nearly one-third of them were clearly dysfunctional.

LIMITATION

As subjects had a greater mean age, the age-related effects probably worsened the psychosocial outcome and reduced the incidence of new substance abuse.

CONCLUSION

Chinese bipolar patients, despite a lower comorbidity of alcohol use disorders, do not have a more favorable long-term psychosocial outcome (marriage, work, and social adjustment) than Western patients.

P2Y receptor linked to phospholipase C: stimulation of neuro 2A cells by UTP and ATP and possible regulation by protein kinase C subtype epsilon

Incubation of Neuro 2A mouse neuroblastoma cells with UTP and UDP results in a concentration-dependent increase in the accumulation of inositol phosphates with equal potency and maximal effect; ATP, ADP, and 2-methylthioadenosine 5'-triphosphate were much less potent, indicating the expression of P2Y receptor in these cells. The effects of UTP and ATP were not affected by pretreatment of cells with pertussis toxin, indicating that the P2Y receptor in Neuro 2A cells is coupled to pertussis toxin-insensitive Gq protein. Short-term (10 min) treatment of cells with 1 microM 12-O-tetradecanoylphorbol 13-acetate (TPA) resulted in the inhibition of the UTP and ATP effects; this inhibitory effect was gradually attenuated with increased length of TPA treatment (1.5-6 h) and was not seen after long-term (24 h) treatment. Western blot analysis showed the expression of protein kinase C (PKC) alpha, epsilon, theta, and zeta in Neuro 2A cells. Translocation of PKC alpha, epsilon, and theta from the cytosol to the membrane was seen after 10 min or 1.5 h of treatment with TPA. However, partial and complete down-regulation of both membrane PKC alpha and theta were seen after 3 and 6 h of treatment, respectively. In contrast, the TPA-induced translocation of PKC epsilon was maintained after 3-6 h of treatment, and almost complete down-regulation occurred only after a 24-h treatment. The observed TPA-induced inhibition of UTP- or ATP-stimulated phosphoinositide hydrolysis, therefore, correlated well with the extent of translocation of PKC epsilon. Phosphoinositide hydrolysis induced by AlF4-, but not Ca2+ ionophores, was inhibited by a 10-min treatment with TPA. This was not seen after a 24-h treatment, indicating that the site of action of PKC epsilon in the P2Y receptor/Gq protein/phospholipase C beta pathway might be the Gq protein. This is the first study to show the existence of the P2Y receptor in Neuro 2A cells and the possible involvement of neuronal PKC epsilon in the regulation of the receptor-mediated phosphoinositide turnover.

Analysis of the effect of pattern adaptation on pattern pedestal effects: a two-process model

Pattern contrast thresholds for vertical Gabor patterns were measured on pattern pedestals that were vertical or horizontal. Contrast of the pedestal was varied to measure the function relating target contrast threshold to pedestal contrast (TvC function). TvC functions were measured without an adaptor and after adaptation to vertical, horizontal and plaid patterns. For a pedestal with the same orientation as the target, the vertical and plaid adapters increased thresholds at low pedestal contrasts, but not high. For the pedestal orthogonal to the target, the same two adaptors increased thresholds over the whole range of pedestal contrasts. These asymmetric effects are described by a model of adaptation and masking derived from a model of masking (Foley, 1994a) by allowing two parameters to vary with the adapt state; one of them is an additive parameter in the denominator of the response function, which can be interpreted as adaptor-produced divisive inhibition that persists after adaptor offset; the other is the sensitivity to pedestal-produced divisive inhibition, which is changed by adaptation for the pedestal orthogonal to the target. Other models do not account for both effects.