Molecular cloning and relationship of highly repetitive Hind III sequences in three cyprinid species: silver carp, bighead carp and grass carp

The genomes of three cyprinid species, silver carp, bighead carp and grass carp, all contain highly repetitive Hind III sequences. There are two types of repeated sequences found in the genome of bighead carp but only one type of repeated sequence found in the genomes of silver carp and grass carp. Their lengths are from 186 to 201 bp. These sequences are arranged tandemly in the genomes. Their copy numbers are about 3.65 x 10(5) per haploid genome and total contents are about 5% of the genomes. The Hind III repetitive sequences of silver carp, bighead carp and grass carp are very similar to one another but completely different from those known repetitive DNAs of common carp, tilapia, pollock and salmon.

Host T-cell primary allosensitization to MHC class-I- and class-II-expressing human cardiac myocytes requires the presence of a second signal

Normal FHCMs, or transformed cell lines derived from FHCMs, such as W1, even after induction of MHC antigens by pretreatment with IFN-gamma, failed to induce proliferation of allogeneic human PBMCs in vitro. To test the hypothesis that antigen-specific T-cell activation and proliferation require not only the binding of the TCR with its ligand, the MHC molecule, but also a second signal that involves the interaction of T-cell surface molecules with their natural ligands on the stimulating cells, a mAb against CD28 was used. Cocultures of allogeneic PBMCs with IFN-gamma-pretreated irradiated FHCMs or the W1 cell line in microtiter plates containing immobilized anti-CD28 mAb induced marked stimulator cells MHC class-II-specific proliferative responses. The W1 cell line and FHCMs failed to express detectable levels of the BB1/B7 molecule (the natural ligand for CD28) as determined by flow microfluorometry or mRNA levels coding for BB1/B7 as determined by RT-PCR. These data suggest that one of the probably reasons for the failure of MHC-expressing cardiac myocytes to induce allogeneic activation is the absence of costimulatory signals.

Temporal and light regulation of the expression of three phytochromes in germinating seeds and young seedlings of Avena sativa L

An oat (Avena sativa L.) plant contains at least three phytochromes, which have monomeric masses of 125, 124, and 123 kilodaltons (kDa) (Wang et al., 1991, Planta 184, 96-104). The 124-kDa phytochrome is most abundant in dark-grown seedlings, while the other two phytochromes predominate in light-grown seedlings. Using three monoclonal antibodies, each specific to one of the three phytochromes, we have monitored by immunoblot assay the expression of these three phytochromes in the 5 d following onset of imbibition of seeds. On a per-organism basis, each of these three phytochromes increased in abundance for the first 3 d in the light, or for the first 4 d in darkness, after which they each began to decrease in quantity. When 3-d-old dark-grown seedlings were transferred to the light, the abundance of each of these three phytochromes decreased both in absolute amount and relative to the phytochrome levels in control seedlings kept in darkness. In contrast, when 3-d-old light-grown seedlings were transferred to darkness, the abundance of the 124-kDa and 125-kDa phytochromes increased while that of 123-kDa phytochrome remained unchanged. In each case, the level of phytochrome was greater than that of control seedlings maintained in the light. Thus, in addition to temporal regulation, all three phytochromes exhibit photoregulated expression at the protein level, although the magnitude of this photoregulation varies substantially.

Spatial distribution of three phytochromes in dark- and light-grown Avena sativa L

We have addressed two issues regarding the spatial distribution of three phytochromes in 3-d-old oat (Avena sativa L.) seedlings. Three monoclonal antibodies, GO-4, GO-7 and Oat-22, were used as probes. Each antibody detects only one of the phytochromes. The first issue is whether any of the phytochromes might be membrane-bound. To address this issue the abundance of each phytochrome in extracts prepared with either a detergent-free or a detergent-containing buffer was compared by immunoblot assay. The detergent-free buffer was formulated to extract only soluble protein, while the detergent-containing buffer was intended to extract both soluble and membrane proteins. None of the data indicate that any of these three phytochromes is membrane-bound in either a dark- or a light-grown seedling. The second issue is whether these three phytochromes are distributed differentially in 3-d-old dark- and light-grown seedlings. When seedlings were dissected into shoots, scutellums, and roots, all three phytochromes were detected in all three fractions from both dark- and light-grown seedlings. Each of the three phytochromes was most abundant in the shoot and least abundant in the root, except that in light-grown seedlings type I, etiolated-tissue phytochrome was more abundant in the root than in either the shoot or the scutellum. When the equivalent fractions dissected from different seedlings were compared, those dissected from dark-grown seedlings contained a higher quantity of each of the three phytochromes than did those dissected from light-grown seedlings, except that green-tissue, type II phytochromes did not differ significantly in the roots. At this level of resolution, no evidence was obtained to indicate a substantive difference among the three phytochromes in their spatial distribution.

Prevalence of attention deficit hyperactivity disorder in primary school children in Taiwan

Chinese versions of Conners' Teacher's Rating Scale (CTRS) and the Werry-Weiss-Peters Activity Scale (WWPAS) were applied to 4,290 randomly selected primary school children in Kaohsiung. Using relative operational characteristic analysis to determine the best cut-off points, the validity of the WWPAS and CTRS for estimating the prevalence of attention deficit hyperactivity disorder (ADHD) was established. It was found that CTRS had satisfactory results, but the WWPAS did not have an optimal cut-off score. Using CTRS as a screening tool, the estimated overall prevalence rate of ADHD among Kaohsiung primary school children was found to be 9.9%, while the rate in boys (14.9%) was 3.3 times higher than in girls (4.5%). The assumption that hyperactivity is uncommon among Chinese children was proven to be unreliable.

Visual processing in pigeon nucleus rotundus: luminance, color, motion, and looming subdivisions

The responses of single cells to luminance, color and computer-generated spots, bars, kinematograms, and motion-in-depth stimuli were studied in the nucleus rotundus of pigeons. Systematic electrode penetrations revealed that there are several functionally distinct subdivisions within rotundus where six classes of visual-selective cells cluster. Cells in the dorsal-posterior zone of the nucleus respond selectively to motion in depth (i.e. an expanding or contracting figure in the visual field). Most cells recorded from the dorsal-anterior region responded selectively to the color of the stimulus. The firing rate of the cells in the anterior-central zone, however, is dramatically modulated by changing the level of illumination over the whole visual field. Cells in the ventral subdivision strongly respond to moving occlusion edges and very small moving objects, with either excitatory or inhibitory responses. These results indicate that visual information processing of color, ambient illumination, and motion in depth are segregated into different subdivisions at the level of nucleus rotundus in the avian brain.

Enterogenous cyst of the fourth ventricle: case report

The authors present an intracranial enterogenous cyst of the fourth ventricle in a Chinese woman having symptoms of headache, dizziness and vertigo for approximately six months. A computerized tomography study of the brain disclosed a low density lesion within the fourth ventricle. A cystic tumor was completely removed and a histopathological examination diagnosed it is an enterogenous cyst; a rare lesion. During the post-operative follow-up, her symptoms gradually resolved and she was free of complaints within two years.

Mice deficient for Rb are nonviable and show defects in neurogenesis and haematopoiesis

The retinoblastoma gene, a prototypic tumour-suppressor gene, encodes a nuclear phosphoprotein (Rb). To understand better the role of Rb in development and in tumorigenesis, mice with an insertional mutation in exon 20 of the Rb-1 locus were generated. Homozygous mutants die before the 16th embryonic day with multiple defects. The haematopoietic system is abnormal; there is a significant increase in the number of immature nucleated erythrocytes. In the nervous system, ectopic mitoses and massive cell death are found, particularly in the hindbrain. All spinal ganglion cells die, but the neural retina is unaffected. Transfer of the human retinoblastoma (RB) mini-transgene into the mutant mice corrects the developmental defects. Thus, Rb is essential for normal mouse development.

[Epidemiologic study of head injuries in Taipei City, Taiwan]

This study was designed to examine the descriptive epidemiology of head injuries in an urban population in the Taiwan area, Taipei City, during the period from July 1, 1987 to June 30, 1988. Clinical records reviewed included emergency room (ER) charts, inpatient charts of 19 major hospitals, death registration forms and medical examiners' reports in this city. A formulated definition was used to identify patients with head injuries. A total of 4,692 cases were collected, which included 4,319 hospital inpatients and 373 non-hospital deaths. The average incidence rate for head injury was 180/100,000 per year, 246/100,000 for males and 111/100,000 for females. The highest incidence rate was observed in the elderly group followed by the age group of 20-29 years. Sixty eight percent of the head injuries were caused by traffic accidents, 59.7 percent of which were involved in motorcycle rides. This rate was higher than those in any western reports. Among the 10-39 age group, the head injuries caused by traffic accidents were mainly due to motorcycle accidents. However, most of the children and the elderly who were injured were either pedestrians or bicycle riders. The average mortality rate was 23/100,000 per year, 34/100,000 for males and 12/100,000 for females. Initially the Glasgow Coma Scale was used in assessing the severity of head injuries. Seventy-two percent of the cases were considered mild, and 28 percent moderate to severe in degree, including 609 deaths.(ABSTRACT TRUNCATED AT 250 WORDS)

Splicing of two alternative exon pairs in beta-tropomyosin pre-mRNA is independently controlled during myogenesis

Two known tissue-specific tropomyosin (TM) isoforms are produced from the rodent beta-TM gene. Skeletal muscle beta-TM uses the alternative exons 6b and 9a and the exon 9a-associated poly(A) site. Fibroblast and smooth muscle TM-1 use exons 6a and 9b and the exon-9b associated poly(A) site. We have identified a new skeletal muscle beta-TM isoform, beta-TM2. beta-TM2 contains exon 6b (muscle) and exon 9b (nonmuscle). Full-length beta-TM2 cDNA clones were isolated from a cDNA library of mouse muscle BC3H1 cells. Its mRNA was also found in mouse skeletal muscle tissue but not in other tissues. beta-TM2 mRNA level and protein synthesis are differentiation-dependent, with a transient high level in the early stages of myogenesis both in BC3H1 cells and in mouse embryo limbs. Trace amounts of beta-TM3 mRNA, the other hybrid form (exons 6a + 9a), were found in less differentiated BC3H1 cells, mouse uterus, heart, and 3T3 fibroblasts but not skeletal muscle tissue. Thus, the selection of the two alternative exons appears to be controlled independently. Furthermore, during myogenesis, there is a sequential switch in the internal alternative exon, the terminal exon, and the poly(A) site from the nonmuscle to the muscle type.

Treatment of blepharospasm, hemifacial spasm and strabismus with botulinum a toxin

Thirty patients with blepharospasm, hemifacial spasm, strabismus and entropion were treated with botulinum A toxin giving satisfactory results. Rapid spasm relief, correction of strabismus and entropion were obtained. Only mild, transient and local side-effects occurred. The patients were followed up for 4-12 weeks with no recurrence. The clinical results show that local injection of a minute dose of botulinum A toxin in treating blepharospasm, hemifacial spasm, strabismus and entropion is a safe, effective and simple method of nonsurgical therapy.

Characterization of human heart-infiltrating cells after transplantation. VI. Differences in the cytokines produced by individual CD4+ cloned T-cell lines with apparently identical antiidiotype-like reactivity

Studies of cultures and cloned T-cell lines from mononuclear cell infiltrates in cardiac biopsy specimens have provided a unique resource to study the cellular basis of human organ allograft rejection. Our laboratory has previously shown that biopsy specimens placed on autologous donor MHC-class-II-specific cloned T-cell lines from previous cardiac biopsies led to the isolation of cloned T-cell lines, which appeared to be functionally "antiidiotypic" in nature. Detailed functional analysis of such CD4+ individual antiidiotype-reactive cloned T-cell lines revealed that although some augmented the proliferative response of autologous idiotype-bearing cloned T-cell lines against donor stimulator cells, others markedly suppressed the proliferative response; thus, although each of these antiidiotype-like reactive cloned T-cell lines appears to specifically react with the same idiotype-bearing donor MHC-class-II-specific cloned T-cell line, they were functionally heterogeneous. Analysis of cytokines secreted by these individual clones showed that the antiidiotype-reactive cloned T-cell lines that suppressed the response of idiotype-bearing cells appear to secrete predominantly interferon gamma, whereas those antiidiotype-reactive cloned T-cell lines that augmented the response do not secrete interferon gamma but secrete interleukin-2, -4, and -6. These preliminary data suggest that differences in the predominant cytokines secreted by these individual antiidiotype-reactive cloned T-cell lines may account for their functional differences.

Indirect presentation of donor histocompatibility antigens contributes to the allogeneic response against human cardiac myocytes

Normal human cardiac myocytes failed to induce proliferative responses of peripheral blood mononuclear cells from major histocompatibility complex (MHC)-disparate individuals. Induction of cell-surface MHC antigens on such myocytes before culture still failed to induce alloproliferative responses. Similar data were obtained with cocultures of a human cardiac myocyte (W1) cell line and allogeneic lymphocytes. Addition of interleukin (IL)-1, IL-2, or IL-1 plus IL-2 failed to reconstitute the alloproliferative response. Of interest was the observation that preincubation of primary cultures of myocytes or the W1 cell line (especially after pretreatment with interferon-gamma) with an autologous enriched population of adherent cells, containing monocytes/macrophages/B cells, markedly augmented the ability of these cells to induce alloproliferative responses. In addition, the specificity of the secondary response of T cells primed against myocytes or the W1 cell line (especially after pretreatment of the myocytes or the W1 cell line with interferon-gamma) appeared to reside at the MHC type of the adherent cells used in the primary phase. These data suggest that adherent cells most likely present donor myocyte-specific MHC or other proteins to allogeneic T cells in the context of the MHC molecules of the adherent cells. Such a finding provides evidence that the indirect pathway of host cellular sensitization may occur in vivo and play a role in chronic graft rejection.

Characterization of human heart-infiltrating cells after transplantation. V. Suppression of donor-specific allogeneic responses by cloned T-cell lines isolated from heart biopsy specimens of patients after transplantation

In vitro culture of heart biopsy specimens from patients after transplantation in media containing recombinant human interleukin-2 led to the exudation of host mononuclear-cell infiltrates. Cloned T-cell lines were prepared from such infiltrates and studied for donor-specific mixed lymphocyte reaction and cytotoxic T-lymphocyte activity. Although most T-cell clones (greater than 50%) showed donor-specific reactivity, a small but distinct frequency (2% to 10%) of the cloned T-cell lines did not proliferate against donor or third-party stimulator cells. Of interest was our finding that addition of these non-donor-reactive cloned T-cell lines to autologous peripheral blood mononuclear cells markedly suppressed their donor-specific, but not third-party major histocompatibility complex, unrelated proliferative response and prevented the generation of donor, but not third-party, major histocompatibility complex unrelated cytotoxic T-lymphocyte function. The suppression was not secondary to lysis of donor stimulator cells, lysis of autologous donor-specific CD4+ lymphoblasts, or by selective consumption of interleukin-2. The suppression was mediated at the initiation of sensitization (precursor cell level). These suppressor cells expressed CD3, CD8, CD45RO, and the alpha, beta T-cell receptor, but not CD4 or CD56. These cloned T-cell lines will provide unique reagents to study the molecular basis by which these cells exert their regulatory function.

Ossification of the posterior cervical longitudinal ligament

Forty patients with cervical myelopathy due to OPLL (Ossification of the Posterior Longitudinal Ligament) of the cervical spine were studied. According to Abe's or Yamamoto's classification, 12 of them had a 50% decrease in the cross-sectional area of the spinal canal. Subtotal vertebrectomy was carried out in 8 of these patients and the remaining 4 patients received posterior decompression. We concluded that anterior decompression, if possible, is the treatment of choice and posterior decompression is recommended only for the longitudinal type involving more than 3 segments.

Choice of 3' cleavage/polyadenylation site in beta-tropomyosin RNA processing is differentiation-dependent in mouse BC3H1 muscle cells

The rodent beta-tropomyosin (TM) gene produces either a 1.2-kilobase (kb) skeletal muscle beta-TM mRNA or a 1.1-kb fibroblast/smooth muscle TM-1 mRNA through tissue-specific alternative exon splicing and 3' cleavage/polyadenylation at two alternative poly(A) sites. beta-TM mRNA contains exon 6b, 9a, and the poly(A) site immediately following exon 9a, whereas TM-1 mRNA contains exon 6a, 9b, and the poly(A) site following exon 9b. We isolated a novel 2.1-kb beta-TM cDNA clone, pUTM, from a cDNA library of 2-day differentiated mouse BC3H1 muscle-like cells. This cDNA contains the entire sequence of mature beta-TM mRNA with a normal but unused poly(A) site associated with exon 9a. Instead, 3' cleavage/polyadenylation of this cDNA occurred at the exon 9b-associated distal poly(A) site, resulting in the retention of a 1-kb intron and the TM-1 exon 9b. We identified a 2.3-kb functional mRNA, UTM RNA, corresponding to pUTM. UTM RNA appeared early during BC3H1 cell differentiation and gradually decreased as the beta-TM mRNA increased. UTM RNA was also detected in mouse C2C12 muscle cells and in skeletal muscle tissue isolated from mouse leg. Thus, in the processing of beta-TM gene transcripts, selection of alternative terminal exons and alternative poly(A) sites are not necessarily linked as they appear to be in other gene systems.

Organization and nucleotide sequence of carp gonadotropin α subunit genes

We have used PCR to amplify and align the sequence of two genes encoding cGTH alpha. Both genes comprise four exons and three introns. The organization of cGTH alpha genes is very similar to that of mammalian GTH alpha genes. However, the cGTH alpha genes only span a region of 1.2 kb which is much smaller than those mammalian GTH alpha genes.

Visual response characteristics of neurons in the nucleus isthmi magnocellularis and nucleus isthmi parvocellularis of pigeons

The visual response characteristics of single cells in the nucleus isthmi (NI) of pigeons were investigated using standard extracellular recording techniques. The results show that both major components of NI, the parvocellular NI (Ipc) and the magnocellular NI (Imc), have a tight retinotopic organization where nasal regions of the visual field are mapped onto the rostral poles of Ipc and Imc, and temporal regions of the visual field are mapped onto the caudal poles. The more ventral regions of these nuclei receive input from more inferior regions of visual space. The receptive fields (RFs) of both Ipc and Imc are large and oval-shaped, and their long axis is oriented vertically in the visual field. Most RFs are distributed on the contralateral visual horizon, and no binocular responses were found in either Ipc or Imc. All of the excitatory RFs of NI cells were surrounded by large inhibitory regions which participated in the dramatic modulation of the driven visual response when a large background pattern was moved across this zone. Although both Ipc and Imc neurons are driven best by small dark spots, some of them also show orientation selectivity to bars which may result from their oval-shaped RF (74% of Imc cells, 20/38, were orientation selective as compared to 10% of the Ipc cells, 3/30). It is suggested that some tectal cells with small RFs, and which originate from a vertically oriented zone may converge onto a single NI neuron to produce the elliptical shaped receptive fields.

Intracranial lipoma in the medulla oblongata

Intracranial lipoma in the medulla oblongata has been rarely reported. Only two cases have been documented in the literature. This report concerns a patient who complained of nuchal soreness and an unstable gait for 6 months. An olivelike lipoma, arising from the posterior aspect of the medulla oblongata and embedded in the lower cranial nerves, was found at suboccipital craniectomy and posterior laminectomy of C1-2. Partial removal of the lipoma was performed for decompression; radical removal would have been hazardous. The clinical symptoms subsided postoperatively. The computed tomography scan and magnetic resonance image proved useful for properative diagnosis.

Localization of functional projections from corpus callosum to cerebral cortex

In 30 patients with intractable generalized epilepsy treated with cerebral commissurotomy, the corpus callosum was stimulated intraoperatively at a 1 cm interval with electric current, and evoked potentials (EPs) were recorded from different areas of the brain for determining the distribution patterns of functional projections from the corpus callosum to the cerebral cortex. The surface of the corpus callosum in man was 12 cm long and it was divided into 12 segments (1 cm each). Stimulation of the first segment resulted in EPs only in the frontal lobe. Stimulation of segments 2-4 produced EPs mainly in the anterior, middle and posterior frontal lobe, anterior and central temporal lobe, rarely in parietal and occipital lobes. Stimulation of segments 5-8 induced EPs mainly in the frontal and temporal lobes, but rarely in the parietal and occipital regions; on stimulation of segments 9-11, EPs occurred only in the parietal and occipital regions. These results were confirmed electrophysiologically in 5 cats and anatomically in 8 cats. These data provide an anatomical basis for selective cerebral commissurotomy in the treatment of intractable epilepsy. Hence in patients with a concentration of epileptic discharges in the frontal lobe, the 4 anterior segments of the corpus callosum should be incised. Epileptic discharges in the frontotemporal region indicates that the middle segments should be incised and epileptic activities originating from the parieto-occipital regions can be treated effectively by selective section of the posterior corpus callosum (segments 9-12).

Xeroderma pigmentosum variant cells are less likely than normal cells to incorporate dAMP opposite photoproducts during replication of UV-irradiated plasmids

Xeroderma pigmentosum (XP) variant patients show the clinical characteristics of the disease, with increased frequencies of skin cancer, but their cells have a normal, or nearly normal, rate of nucleotide excision repair of UV-induced DNA damage and are only slightly more sensitive than normal cells to the cytotoxic effect of UV radiation. However, they are significantly more sensitive to its mutagenic effect. To examine the mechanisms responsible for this hypermutability, we transfected an XP variant cell line with a UV-irradiated (at 254 nm) shuttle vector carrying the supF gene as a target for mutations, allowed replication of the plasmid, determined the frequency and spectrum of mutations induced, and compared the results with those obtained previously when irradiated plasmids carrying the same target gene replicated in a normal cell line [Bredberg, A., Kraemer, K. H. & Seidman, M. M. (1986) Proc. Natl. Acad. Sci. USA 83, 8273-8277]. The frequency of mutants increased linearly with dose, but with a slope 5 times steeper than that seen with normal cells. Sequence analysis of the supF gene showed that 52 of 53 independent mutants generated in the XP variant cells contained base substitutions, with 62 of 64 of the substitutions involving a dipyrimidine. Twenty-eight percent of the mutations involved A.T base pairs, with the majority found at position 136, the middle of a run of three A.T base pairs. (In the normal cells, this value was only 11%.) If the rate of excision of lesions from supF in the two cell lines is equal, our data suggest that XP variant cells are less likely than normal cells to incorporate dAMP opposite bases involved in photo-products. If such incorporation also occurs during replication of chromosomal DNA, this could account for the hypermutability of XP variant cells with UV irradiation.

Abnormal expression of histocompatibility and mitochondrial antigens by cardiac tissue from patients with myocarditis and dilated cardiomyopathy

Autoantibodies against the adenine nucleotide translocator (ANT), the branched chain alpha-ketoacid dehydrogenase (BCKD) complex proteins, and myosin have been implicated in the pathogenesis of human dilated cardiomyopathy (DCM). Cardiac tissue from patients with DCM and, for control purposes, cardiac tissue from patients with other forms of cardiomyopathy and from patients with no history of cardiac disease were stained with heterologous and ANT-, BCKD-, and myosin-specific affinity-purified sera from DCM patients. Data demonstrate that although anti-myosin stains tissues from both patients and normal controls, the ANT- and BCKD-specific heterologous and affinity-purified sera from DCM patients stain only cardiac tissues from DCM patients. Intense staining in patchy areas of cardiac tissue suggests that abnormal increased expression of these putative autoantigens occurs in discrete areas of cardiac myocytes. The reactivity of the antisera was organ specific and only seen in tissues from DCM patients. The organ and disease specificity of these findings suggests that such expression may play an important role in the pathogenesis of human DCM.

Influence of cytokines and immunosuppressive drugs on major histocompatibility complex class I/II expression by human cardiac myocytes in vitro

Human cardiac myocytes do not express detectable levels of major histocompatibility complex (MHC) class II antigens and express low levels, if any, of MHC class I antigens. During rejection episodes, cardiac biopsies show massive increases of MHC antigens, which are thought to be induced by cytokines released by donor-sensitized recipient mononuclear cells. In efforts to determine the nature of the cytokines that induce MHC expression on cardiac myocytes, human fetal cardiac myocyte cultures were established. Interferon-alpha (IFN-alpha), interferon-gamma (IFN-gamma), interleukin (IL)-1, IL-2, IL-3, IL-4, and tumor necrosis factor (TNF)-alpha were added to these cultures and dose/kinetics of MHC class I/II induction quantitated. Data show that IFN-gamma induces both MHC class I and II expression, and all the other cytokines (except IL-2) induce only MHC class I but not class II. Cytokines used in combination showed that IFN-alpha with TNF-alpha was the only combination that induced MHC class II expression. Addition of immunosuppressive drugs such as cytoxan, azathioprine, cyclosporine-A, and FK-506, even when added at the initiation of the cultures, did not appreciably affect the ability of the appropriate cytokines to induce MHC expression by the myocytes in vitro.