Prognostic factors for idiopathic pulmonary fibrosis: clinical, physiologic, pathologic, and molecular aspects

BACKGROUND

Previous studies identified clinical and physiologic factors of idiopathic pulmonary fibrosis (IPF) that are related to an increased risk of mortality. But there are few studies about histologic and molecular approach.

OBJECTIVE

We investigated whether the C-reactive protein (CRP), fibroblastic foci, phosphorylated Smad2/3 (p-Smad2/3), tumor growth factor-beta (TGF-beta), TGF-beta receptor II (TbetaRII), and the polymorphism of the TGF-beta1 codon 10 are associated with the progression of IPF patients.

DESIGN

Eighty-six IPF patients who underwent surgical lung biopsies were examined. For each patient, clinical and physiologic parameters were investigated, and we performed immunohistochemical staining for p-Smad2/3 and TbetaRII, and genotyping of the TGF-beta1 codon 10 polymorphism.

RESULTS

Age at diagnosis, gender, symptom duration, and smoking status did not show a significant association. However, the amount of smoking (p = 0.002), severe reduction in the percentages of predicted forced vital capacity (p = 0.013) and diffusion lung capacity of carbon monoxide (p = 0.023), CRP (p = 0.009) at diagnosis, and fibroblastic foci (p = 0.026) were associated with a poor prognosis. Cellularity, fibrosis, expression level of p-Smad2/3 and TbetaRII, and genotype of the TGF-beta1 codon 10 polymorphism did not have a statistically significant association with the prognosis.

CONCLUSION

This study confirmed the amount of smoking, abrupt decrease in follow-up pulmonary function parameters, fibroblastic foci, and increased levels of CRP concentration at diagnosis were significantly associated with poor survival. Larger studies are required to confirm all prognostic factors including CRP.

Early development of reflux esophagitis after successful Helicobacter pylori eradication in superficial gastritis

The relationship between gastroesophageal reflux disease (GERD) and Helicobacter pylori (H. pylori) eradication is still debated. Recently, we had a patient of GERD who had developed it shortly after H. pylori eradication therapy. A 72-year-old man was diagnosed by endoscopy as suffering from severe superficial gastritis in the stomach body. A rapid urease test showed H. pylori infection. He was then started on proton pump inhibitor (PPI) based therapy for two weeks eradicating H.pylori. After completion of H. pylori eradication, he complained of a heart-burn sensation. Follow-up endoscopy showed reflux esophagitis, of grade B according to the Los Angeles classification. Since the patient had developed GERD after completion of the triple therapy, their suggests that H. pylori eradication must have triggered the development of de novo GERD after a short period of time.

Transcultural adaptation and testing of psychometric properties of the Korean version of the Hip Disability and Osteoarthritis Outcome Score (HOOS)

OBJECTIVE

Translation and transcultural adaptation of the Hip Disability and Osteoarthritis Outcome Score (HOOS LK 2.0) into Korean language was performed, followed by test of psychometric properties.

DESIGN

A Korean version of the HOOS was produced according to internationally recommended guidelines, which included forward translation, reconciliation, back translation, harmonization, cognitive debriefing and proof reading. The psychometric properties including reliability and validity were evaluated. The reliability, including the internal consistency and test-retest reliability, was then evaluated in a hip osteoarthritis population (OA group, n=75). The validity, including the convergent validity was assessed comparing HOOS with the Short Form-36 (SF-36) and pain on a visual analogue scale (VAS) scale. Responsiveness was evaluated in a population scheduled for total hip arthroplasty (THA group, n=35).

RESULTS

All subscales of the HOOS showed satisfactory internal consistency (Cronbach's alpha>0.7) without floor and ceiling effects. Intraclass correlation coefficient (ICC) spanned from 0.78 to 0.93. In terms of convergent validity, Activity of Daily Living (ADL) subscale showed the strongest correlations with Physical Function (PF) (r=0.801) and Bodily Pain (BP) (r=0.810) in the subscales of SF-36. For responsiveness, all HOOS subscale scores improved significantly (P<0.05) postoperatively.

CONCLUSIONS

The Korean version of HOOS showed satisfactory internal consistency, test-retest reliability, convergent validity, and responsiveness. This study shows that the HOOS questionnaire developed in West is, with transcultural adaptation, relevant for use among patients in East Asia.

Vitamin C protects against ethanol and PTZ-induced apoptotic neurodegeneration in prenatal rat hippocampal neurons

Exposure to alcohol during brain development may cause a neurological syndrome called fetal alcohol syndrome, characterized by pre- and postnatal growth deficiencies, craniofacial anomalies, and evidence of CNS dysfunction. The objective of this study was to evaluate pentylenetetrazol (PTZ) and ethanol effects on Bax, Bcl-2 expression, which further induced activation of caspase-3, release of cytochrome-c from mitochondria, and to observe the protective effects of vitamin C (vit-C) against PTZ and ethanol-induced apoptotic neurodegeneration in primary-cultured neuronal cells at gestational day 17.5. Apoptotic neurodegeneration and neuroprotective effect of vit-C were measured by using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide assay, Western blot analysis, which further conformed by the measurement of mitochondrial membrane potential using JC-1 detection kit and immunofluorescence analysis. The results showed that PTZ and ethanol produced extensive Bax-dependent caspase-9 and caspase-3 activation and caused neuronal apoptosis. Furthermore, the cotreatment of vit-C along with ethanol and PTZ showed significantly decreased expression of Bax, caspase-9, caspase-3, cytochrome-c, and significantly increased expression of antiapoptotic Bcl-2 protein when compared with control group. Our findings indicate that PTZ and ethanol activate an intrinsic apoptotic death program in neurons that is likely to contribute to the neuropathologic effects in fetal alcohol exposure, and vit-C can prevent some of the deleterious effects of PTZ and ethanol on the developing brain. The available experimental evidence and the safety of vit-C in pregnancy suggest the experimental use of ascorbic acid as a new and effective protective agent ethanol and PTZ-induced apoptotic neurodegeneration.

Health behaviour and quality of life in Korean adults with respiratory disease: National Health Survey, 2005

OBJECTIVES

To describe disease management, health behaviour, psychological health and quality of life (QOL) in people with chronic respiratory disease (CRD).

METHODS

We analysed data from 798 adults with CRD drawn from the Korean National Health and Nutrition Examination Survey (KNHANES) 2005: 514 subjects with asthma alone, 258 with chronic obstructive pulmonary disease (COPD) alone, and 56 with asthma and COPD.

RESULTS

Disease management and health behaviour in this cohort were poor. One third of the cohort was not seeking any medical treatment, although many were currently experiencing respiratory symptoms. Twenty-six per cent of the subjects were current smokers who averaged 0.8 packs/day. More than half of the subjects did not exercise, only half of the subjects had regular health examinations and one third of the subjects did not get enough sleep. The study population exhibited poor psychological indices, functional health status and QOL. The combined asthma and COPD group was characterised by an increased frequency of problems related to functional status and QOL.

CONCLUSIONS

People with CRD are at high risk for functional limitations, unhealthy behaviour, poor mental status and poor QOL. A comprehensive disease management programme for people with CRD should be developed using collaborative team efforts.

Effects of direct-fed microbials on growth performance, gut morphometry, and immune characteristics in broiler chickens

This study was conducted to compare growth performance, gut morphometry, and parameters of local and systemic immunity in broiler chickens fed for 22 consecutive days with a diet supplemented with Bacillus spp. as direct-fed microbials (DFM), a commercial product incorporating 3 DFM, or a nonsupplemented diet. Direct-fed microbials did not significantly modify BW gain and most failed to affect serum antibody levels in response to immunization with a recombinant Eimeria protein. However, altered intestinal morphometric measurements were readily apparent in DFM-fed chickens as revealed by increased villus height and crypt depth compared with non-DFM-fed controls. In addition, serum levels of alpha-1-acid glycoprotein as an inflammatory marker were reduced in DFM-fed birds, whereas splenic lymphocyte proliferation, intestine intraepithelial lymphocyte subpopulations, and cytokine mRNA levels in intraepithelial lymphocytes were increased, decreased, or unchanged compared with controls depending on the DFM used. These results provide a rational scientific basis for future studies to investigate DFM as immunomodulating agents to enhance host protective immunity against enteric pathogens in broiler chickens.

Ethanol and PTZ effects on siRNA-mediated GABAB1 receptor: down regulation of intracellular signaling pathway in prenatal rat cortical and hippocampal neurons

GABA(B) receptors (R) are widely expressed and distributed in the nervous system, and have been implicated in variety of neurodegenerative and pathophysiological disorders. However, the exact molecular mechanism regarding responsibility of GABA(B1)R in downstream signaling pathway is not well understood. The present study was undertaken to explore the downstream signaling and role of GABA(B1)R upon acute ethanol and pentylenetetrazol (PTZ) exposure for (20 min) in cortical and hippocampal neuronal cell cultures by using GABA(B1)R RNA interference (i) (30 nM, 48 h) at gestational days 17.5. The results showed that GABA(B1)R and protein kinase A-alpha (PKA) showed decreased expression upon ethanol and PTZ exposure in cortical and hippocampal neurons during transfected and nontransfected conditions, whereas these effects could lead to significant changes in phosphorylation of cAMP-response element binding protein (p-CREB) expression where GABA(B1)R was knocked down. Furthermore, intracellular Ca(+2) concentrations were also reduced in some groups after transfection with GABA(B1)R RNAi. These results showed a critical role of GABA(B1)R upon ethanol and PTZ exposure by modulating downstream signaling pathway. Finally, these findings suggested that inhibition of GABA(B1)R results in the modulation of PKA, p-CREB pathway may play a role in long-term changes in the nervous system, and may be an underlying cause of ethanol's effects.

Low-dose intra-arterial urokinase and aggressive mechanical clot disruption for acute ischemic stroke after failure of intravenous thrombolysis

BACKGROUND AND PURPOSE

Intravenous (IV) thrombolysis often fails to achieve recanalization of occluded cerebral arteries, especially in patients with proximal large arterial occlusions. The goal of this study was to assess the feasibility, safety, and efficacy of low-dose intra-arterial (IA) urokinase and aggressive mechanical clot disruption (AMCD) after failure of IV thrombolysis for acute ischemic stroke.

MATERIALS AND METHODS

We prospectively enrolled 12 patients with acute ischemic stroke who initially received IV recombinant tissue plasminogen activator (rtPA) and were subsequently treated with combined low-dose IA urokinase and AMCD. Time to treatment, urokinase dose, duration of the procedure, recanalization rates, and symptomatic hemorrhage were analyzed. Clinical outcome measures were assessed on admission and at discharge (National Institutes of Health Stroke Scale [NIHSS]), and at 3 months after treatment (modified Rankin Scale [mRS]).

RESULTS

Median NIHSS score on admission was 17. Median time from symptom onset to IV rtPA was 120 minutes, and median time from symptom onset to IA therapy was 230 minutes. The median duration of IA therapy was 55 minutes. Median dose of urokinase was 300,000 U. Recanalization (thrombolysis in cerebral ischemia grade II or III) was achieved in all patients. No procedure-related complications were observed. There was no symptomatic hemorrhage. At discharge, median NIHSS score was 3. The 3-month outcome was excellent (mRS, 0-1) in 8 patients, good (mRS, 2) in 1 patient, and poor (mRS, 3-5) in 3 patients. There was no hospital or 3-month mortality.

CONCLUSIONS

In this study, combination therapy with low-dose IA urokinase and AMCD is safe and effective after failed IV thrombolysis in patients with acute ischemic stroke. A high rate of recanalization, low rate of symptomatic hemorrhage, and excellent functional outcome can be achieved.

Endovascular treatment of unruptured intracranial aneurysms in the elderly: analysis of procedure related complications

INTRODUCTION

The management of unruptured intracranial aneurysms in the elderly remains controversial. Treatment risks are thought to be higher in this group. Large series assessing endovascular treatment of unruptured intracranial aneurysms in the elderly are lacking. Our single center endovascular experience in treating unruptured intracranial aneurysms in the elderly is presented.

METHODS

77 patients, 70 years or older, were referred to the endovascular neurosurgery service for treatment of an unruptured intracranial aneurysm between February 2000 and May 2008. Hospital records, operative reports, angiograms and radiology reports were reviewed and analyzed retrospectively.

RESULTS

99 aneurysms were treated in 77 patients in 102 procedures. Mean patient age was 75±4 years, and the average aneurysm size was 11±7 mm. Adjuvant techniques were used in 66% of cases. Endovascular procedures included coiling alone (32%), balloon assisted coiling (19%), stent assisted coiling (37%), balloon assisted stent and coiling (8%), stent only (1%) and glue (2%). The permanent morbidity and mortality rates were 1% and 3%, respectively. Four adverse events were attributed to the patient's age. Posterior circulation aneurysms were associated with more adverse events (41%) than anterior circulation aneurysms (14%). Endovascular treatments using adjuvant techniques were associated with a higher complication rate than coiling alone.

CONCLUSIONS

With only a 4% permanent rate of neurological morbidity and mortality, endovascular treatment of unruptured aneurysms can be performed safely in the elderly. Age should not be the limiting factor when considering endovascular therapy.

Minimally invasive thoracic corpectomy and anterior fusion in a patient with metastatic disease: case report and review of the literature

For patients with metastatic disease to the spine there are numerous surgical approaches for decompression of neural elements and maintenance of mechanical stability. The challenge is to accomplish this while minimizing patient morbidity. Here we report on the feasibility and utility of a minimally invasive extreme lateral approach to the mid to high thoracic spine for anterior decompression and fusion.

Brain abnormalities in Sjogren syndrome with recurrent CNS manifestations: association with neuromyelitis optica

Background and objectives

Optic neuritis or longitudinally extensive myelitis in Sjogren syndrome (SS) suggests a neuromyelitis optica spectrum disorder (NMOSD). However, brain abnormalities of SS remain to be elucidated for the association with neuromyelitis optica (NMO).

Methods

Twelve primary SS patients (all women, 42 ± 13.2 years) who had recurrent central nervous system (CNS) manifestations with brain involvement were retrospectively identified. Brain MRI, and neurologic and serologic findings were analyzed with the measurement of anti-aquaporin-4 antibody (AQP4-Ab).

Results

All patients showed brain lesions characteristic of NMO as follows: 1) the involved sites adjacent to the third and fourth ventricles and in the posterior limb of the internal capsule, 2) unique configurations, such as the longitudinal course from the internal capsule to the midbrain, large cerebral or cerebellar lesions over 3 cm, and cavity-like formations. AQP4-Ab was positive in six of eight patients tested, and all the seropositive patients showed lesions with increased diffusion, suggestive of vasogenic edema. Four patients met the revised criteria of NMO, and nine had features of NMOSDs. Of the remaining three patients showing only brain involvement, one had AQP4-Ab.

Conclusions

This study demonstrates that SS patients with recurrent CNS involvement have brain abnormalities characteristic of NMO and AQP4-Ab in Korea. The presence of AQP4-Ab in one SS patient with only brain involvement may suggest that the coexistence of NMO should be explored in SS patients with recurrent CNS manifestations, even without optic neuritis or myelitis.

A Ubiquitous Chronic Disease Care system using cellular phones and the internet

AIMS

The rapidly increasing prevalence of chronic diseases is an important challenge to healthcare systems worldwide. To improve the quality and efficiency of chronic disease care, we investigated the effectiveness and applicability of the Ubiquitous Chronic Disease Care (UCDC) system using cellular phones and the internet for overweight patients with both Type 2 diabetes and hypertension.

METHODS

We conducted a randomized, controlled clinical trial over 3 months that included 123 patients at a university hospital and a community public health centre.

RESULTS

After 12 weeks, there were significant improvements in HbA(1c) in the intervention group (7.6 +/- 0.9% to 7.1 +/- 0.8%, P < 0.001) compared with the control group (7.4 +/- 0.9% to 7.6 +/- 1.0%, P = 0.03). Furthermore, we observed a significant reduction in systolic and diastolic blood pressure, as well as improvements in total cholesterol, low-density lipoprotein-cholesterol and triglyceride levels in the intervention group. Furthermore, there was a significant increase in adiponectin levels in the intervention group compared with the control group, although high-sensitivity C-reactive protein and interleukin-6 levels did not change in either group.

CONCLUSIONS

The novel UCDC system presented in this paper improved multiple metabolic parameters simultaneously in overweight patients with both Type 2 diabetes and hypertension.

Growth, characterization and technological applications of semiconductor SnO2 nanotubes and In2O3 nanowires

Tin dioxide nanotubes (200 nm in diameter) were synthesised by the sol-gel template method. The gas sensitivity of SnO2 nanotubes has been investigated. Due to the small grain size and large amount of grain boundary, SnO2 nanotubes demonstrated good sensitivity in sensing ethanol gas and had an ability to detect ammonia gas without any doping or surface modification. In2O3 semiconductor nanowires were synthesized efficiently by the chemical vapor deposition method through carbon thermal reduction. The diameter, length and morphologies of In2O3 nanowires can be varied by controlling the synthetic conditions. The In2O3 nanowires were characterised by field emission scanning electron microscopy (FE-SEM) and high resolution transmission electron microscopy (HRTEM). The application of In2O3 nanowires for gas sensors was tested.

Residual pelvic rotation after single-event multilevel surgery in spastic hemiplegia

Our aim in this retrospective study of 52 children with spastic hemiplegia was to determine the factors which affected the amount of residual pelvic rotation after single-event multilevel surgery. The patients were divided into two groups, those who had undergone femoral derotation osteotomy and those who had not. Pelvic rotation improved significantly after surgery in the femoral osteotomy group (p < 0.001) but not in the non-femoral osteotomy group. Multiple regressions identified the following three independent variables, which significantly affected residual pelvic rotation: the performance of femoral derotation osteotomy (p = 0.049), the pre-operative pelvic rotation (p = 0.003) and the post-operative internal rotation of the hip (p = 0.001). We concluded that there is a decrease in the amount of pelvic rotation after single-event multilevel surgery with femoral derotation osteotomy. However, some residual rotation may persist when patients have severe rotation before surgery.

In vivo and in vitro ethanol exposure in prenatal rat brain: GABA(B) receptor modulation on dopamine D(1) receptor and protein kinase A

We have investigated the effects of prenatal ethanol exposure on GABA(B) receptors (GABA(B)Rs), protein kinase A (PKA), and DA D(1) receptor (DAD(1)R) expressions. GABA(B1)R and GABA(B2)R showed different age-dependent expressions in in vivo fetal rat forebrain from gestational days (GD) 15.5 to 21.5 upon 10% ethanol treatment to mother, with and without baclofen at a dose of 10 mg/kg body weight/day. The protein level changes could not be attributed to changes in the level of transcription since GABA(B)R mRNA presented different expression patterns upon in vivo ethanol treatment. Using in vitro cultivated cortical neurons from GD 17.5 fetuses, we also explored the modulatory effects of ethanol on PKA and DAD(1)R through GABA(B)Rs, under 50 microM baclofen and 100 microM phaclofen administrations, with or without 100 mM of ethanol treatment in the culture media. The results showed that 20 min ethanol treatment without baclofen or phaclofen had increasing effects on both the GABA(B)Rs. Further, baclofen and phaclofen administration significantly affected PKA and GABA(B)R levels upon 20 min and 1 h ethanol treatment. In contrast, DAD(1)R showed increasing effects upon ethanol treatment, which was modulated by GABA(B)R's agonist baclofen and antagonist phaclofen. Therefore the present study suggested that the GABA(B)R activity could modulate ethanol's cellular effects, which possibly including PKA and DAD(1)R activities, and may be an underlying cause of ethanol's effects.

Effects of lysine intake during late gestation and lactation on blood metabolites, hormones, milk composition and reproductive performance in primiparous and multiparous sows

Modern genotype primiparous and multiparous sows (Yorkshire x Landrace, n=48) were used to evaluate effects of dietary lysine intake during late gestation and lactation, and their interaction on reproductive performance. Sows were randomly allotted to two gestation lysine (G, 0.6% or 0.8% lysine) treatments based on parity in a 2 x 2 factorial arrangement, and each treatment had 12 replicates comprising 1 sow. Then all the sows were assigned to two lactation lysine (L, 1.0% or 1.3% lysine) treatments within parity and gestation treatments in a 2 x 2 x 2 factorial design, and each treatment comprised six replicates with 1 sow/replicate during lactation. Feeding higher lysine level during gestation increased sow body weight and backfat thickness (P=0.001) and body condition was better (P=0.001) in multiparous than that of primiparous sows. Both of the lysine levels during lactation and parity influenced sow body condition and reproductive performance (P<0.05). Higher lysine intake during lactation increased the concentrations of total solids (P=0.024), protein (P=0.001) and solids not-fat (P=0.042) in colostrum and total solids (P=0.001), protein (P=0.001), fat (P=0.001) and solids not-fat (P=0.005) in milk. Protein concentration of milk was greater (P=0.001) in multiparous sows than that of primiparous sows. Feeding of high lysine diets resulted in an increment of plasma urea N (P=0.010; P=0.047) and a decrease of creatinine (P=0.045; P=0.002) on the day of postfarrowing and weaning, respectively. Furthermore, as lysine intake increased, the secretions of insulin, FSH, and LH were increased (P<0.05) and multiparous sows showed higher (P<0.05) concentrations of FSH and LH pulses on the day of postfarrowing and weaning, respectively. These results indicated that higher lysine intake than that recommended by NRC [NRC, 1998. Nutrient Requirements of Swine, 10th ed. National Academy Press, 458 Washington, DC] could improve sow performance during late gestation and lactation. Furthermore primiparous sows need higher lysine intake than multiparous sows. Moreover, nutritional impacts on reproduction may be mediated in part through associated effects on circulating LH concentration.

Overview of the cell cycle

Progression through the cell cycle is regulated by inductive signals from outside the cell and intracellular signal pathways, while the cycle itself is regulated by cyclin-dependent kinases (CDKs). An understanding of the functions of these molecules is necessary to understand the processes of mitosis, differentiation, senescence, apoptosis, and tumorigenesis. This overview reviews the current state of knowledge for the biology of the cell-cycle, the CDKs, the role of proteolysis, targets of the cell cycle machinery, and a paradigm of cell cycle analysis.

Low levels of serum cholesterol and albumin and the risk of community-acquired pneumonia in young soldiers

SETTING

The risk factors of community-acquired pneumonia (CAP) in high-risk groups have been examined in many studies. Such studies, however, have limited application for young people in special environments.

OBJECTIVE

To study the risk factors of CAP in young soldiers.

DESIGN

A hospital-based case-control study was carried out during the two winters between 2003 and 2005. A total of 255 CAP cases aged 18-23 years were enrolled and were matched by age and date of hospitalisation with 255 controls.

RESULTS

All CAP cases and 148 controls (58.0%) were military trainees. Most cases (96.1%) were non-severe CAP (pneumonia severity index risk class 1). Serum levels of total cholesterol, albumin, total protein and body mass index (BMI) were lower in CAP cases than in controls. In conditional logistic regression analysis, an increased risk of CAP was independently associated with military trainees, low levels of cholesterol and albumin. However, low BMI (<18.5 kg/m(2)) was not found to be associated with the risk of CAP after adjusting for other factors.

CONCLUSION

In Korea, the risk of CAP is significantly high in military trainees, with low levels of cholesterol and albumin being associated with the development of CAP in young soldiers.

Ethanol's effect on intracellular signal pathways in prenatal rat cortical neurons is GABAB1 dependent

To confirm the modulation role of GABA(B) on ethanol' effects, we studied the effects of ethanol on the neuronal intracellular signals, protein kinase A (PKA) and cAMP-response element binding protein (CREB), by using a system where GABA(B1) receptors were specifically knocked down in the in vitro cultivated cortical neurons. The results showed that the PKA alpha subunit was increased with ethanol treatment, and could be further increased by administering baclofen and phaclofen. By contrast, baclofen and/or phaclofen could decrease ethanol's up-regulation effects on PKA alpha subunit expression in primary cultured cortical neurons in which the GABA(B1) receptor was specifically knocked down using GABA(B1) receptor RNA interference. Furthermore, these effects could lead to changes of phospho (p)-CREB expression, which showed the same expression pattern as PKA. Finally, we observed changes of GABA(B1), PKA, and p-CREB distribution within the same neuronal cells. These results showed that the GABA(B) receptors are critical to ethanol's cellular effects, which occur via modulating the PKA and CREB transcription pathway, and may be an underlying cause of ethanol's effects.

Anisotropy of the Sommerfeld coefficient in magnesium diboride single crystals

The anisotropic field dependence of the Sommerfeld coefficient gamma has been measured down to B-->0 by combining specific heat and Hall probe magnetization measurements in MgB2 single crystals. We find that gamma(B,theta) is the sum of two contributions arising from the sigma and pi band, respectively. We show that gammasigma(B,theta)=B/Bc2(theta) where Bc2(theta)=Bc2ab/sqrt[sin2theta+Gamma2cos2theta] with Gamma approximately 5.4 (theta being the angle between the applied field and the c axis) and gammapi(B,theta)=gammapi(B)=B/Bpi(B). The "critical field" of the pi band Bpi is fully isotropic but field dependent increasing from approximately 0.25 T for B< or =0.1 T up to 3 T approximately Bc2c for B-->3 T. Because of the coupling of the two bands, superconductivity survives in the pi band up to 3 T but is totally destroyed above for any orientation of the field.

Prenatal GABAB1 and GABAB2 receptors: cellular and subcellular organelle localization in early fetal rat cortical neurons

Gamma-aminobutyric acid (GABA)(B) receptors appear to influence developmental events, depending on whether they are found at a synapse or in extrasynaptic areas. Little, if anything, is known as to the cellular and subcellular localization of GABA(B1) and GABA(B2) receptors during early fetal development. We used Western blots, immunohistochemistry, and postembedding immunoelectronmicroscopy to investigate fetal rat brain expression and distribution of these receptor proteins. GABA(B1) is expressed as early as gestational day (GD) 11.5 and 12.5, with immunoreactivity found in the all neuroepithelium, and a high expression in the mantel zone and the cortical area's plate; no immunolabeling for GABA(B2) receptor was observed. Our immunogold studies define a pattern of early GABA(B1) receptor protein in dendrite processes, endoplasmic reticulum, and axon terminals of the cortical neuroepithelium on GD 11.5. On GD 12.5, GABA(B1) receptor immunogold was found in dendrite processes, spines and tree, axon terminals, mitochondria, and intracellular organelles of the cortical neuroepithelium. No synapse formation was apparent as no synaptophysin could be found on either GD 11.5 or 12.5. We suggest that GABA(B1) has a functional role in the early fetal brain during neuronal proliferation and migration, and that it is different from the established functional GABA(B) receptor.