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Characterization of an inversion on the long arm of chromosome 10 juxtaposing D10S170 and RET and creating the oncogenic sequence RET/PTC.

RET/PTC is a transforming sequence created by the fusion of the tyrosine kinase domain of the RET protooncogene with the 5' end of the locus D10S170 designated by probe H4 and is frequently found activated in human papillary thyroid carcinomas. RET and D10S170 have been mapped to contiguous regions of the long arm of chromosome 10: q11.2 and q21, respectively. To identify the mechanism leading to the generation of the oncogenic sequence RET/PTC, a combined cytogenetic and molecular analysis of several cases of papillary thyroid carcinomas was done. In four cases the results indicated that these tumors had RET/PTC activation and a paracentric inversion of the long arm of chromosome 10, inv(10)(q11.2q21), with breakpoints coincident with the regions where RET and D10S170 are located. Therefore, a chromosome 10q inversion provides the structural basis for the D10S170-RET fusion that forms the hybrid transforming sequence RET/PTC.

Blotting, Southern

Familial inversion of chromosome No. 8: an affected child and a carrier fetus.

An infant with multiple congenital anomalies was found to have a duplication-deficiency disorder involving chromosome No. 8. The abnormality was identified as an unbalanced recombinant inherited from the mother who was a carrier of a pericentric inversion of chromosome No. 8. The inversion was observed in several members of this family, including a fetus who was diagnosed by an amniocentesis. The inverted chromosome was demonstrated only with the use of a differential staining technique, in this case, by trypsin-Giemsa banding.

Amniocentesis

Identification of CXCL13 as an agonist and CXCL11 as an inverse agonist for the viral G protein-coupled receptor ORF74.

Kaposi's sarcoma-associated herpesvirus (KSHV) establishes latent infection in humans, but under conditions of immune suppression, it may reactivate and contribute to severe diseases, including Kaposi's sarcoma (KS) and B-cell malignancies. The KSHV genome encodes a single G protein-coupled receptor (GPCR), open reading frame 74 (ORF74), which shows homology to human chemokine receptors. Since its identification in 1996, ORF74 has subsequently been shown to interact with a broad range of human CXC chemokines, as well as CCL1 and the viral chemokine vCCL2. Compared with many human chemokine receptors, ORF74 displays high basal activity. These properties allow ORF74 to deregulate host cellular pathways through constitutive and chemokine-modulated signaling. In this study, we evaluated several human chemokines that, to our knowledge, had not previously been tested in ORF74-dependent cellular assays. Whereas CXCL9, CXCL14, CXCL16 and CXCL17 did not interact with ORF74, CXCL13 was identified as an additional ORF74 agonist and CXCL11 as an inverse agonist. CXCL13 dose-dependently induced ORF74-mediated Ca2+ release, β-arrestin1/2 recruitment and chemotaxis, and enhanced basal nuclear factor κB (NF-κB) activity in ORF74-expressing cells. In contrast, CXCL11 showed no detectable ORF74 agonist activity in the calcium mobilization or chemotaxis assay, but antagonized CXCL1-induced responses in both readouts. CXCL11 also elicited inverse agonist-like responses in β-arrestin1/2 recruitment assays and reduced basal NF-κB signaling. Our study thus reveals CXCL13 and CXCL11 as two additional chemokine ligands for ORF74, further expanding the pharmacological profile of this viral GPCR.

Humans

Inverse relationship in Jamaica between plasma high-density lipoprotein cholesterol concentration and coronary-disease risk as predicted by multiple risk-factor status.

1. The relation between plasma high-density lipoprotein (HDL) cholesterol concentration and multiple coronary-risk factor status has been assessed in fifty-two middle-aged clinically healthy men from urban and rural Jamaica. 2. Rural hill-farmers had a superior exercise performance (assessed by the responses to submaximal test exercise), less body fat, and lower fasting levels for plasma total cholesterol, low-density liproprotein (LDL) cholesterol, total triglyceride and blood glucose than urban businessmen. Mean plasma HDL cholesterol was considerably higher in farmers then businessmen. 3. Multilinear regression analysis showed HDL cholesterol concentration to be independently and inversely correlated with plasma triglyceride, LDL cholesterol and diastolic blood pressure and that these relationships applied across the urban and rural sub-groups. There was also some evidence that HDL cholesterol concentration increased with stature. When these factors were taken into account, age, ethnic group, adiposity, weight, exercise performance, smoking history and blood glucose made no further significant contribution to the prediction of HDL cholesterol concentration. 4. Thus plasma HDL cholesterol concentration was highest in those subjects with the lowest coronary-risk as predicted by their multiple risk-factor status, an observation which supported other evidence that coronary-risk is inversely related to plasma HDL concentration. 5. The results raise the possibility that coronary-risk can be more simply estimated from the plasma HDL cholesterol concentration than from a consideration of other major lipid risk factors and blood pressure.

Adult

Membrane topology inversion of GGCX mediates cytoplasmic carboxylation for antiviral defense.

Mitochondrial antiviral signaling protein (MAVS) is an adaptor involved in antiviral immunity, but its regulation is not fully understood. We identified carboxylation of MAVS by vitamin K (VK)-dependent γ-glutamyl carboxylase (GGCX), which was unexpected owing to the reported membrane topology of GGCX. We found that GGCX could undergo topology inversion to carboxylate MAVS within the cytoplasm. This carboxylation enhanced the ability of MAVS to induce type I interferons while suppressing the induction of apoptosis. Genetic knockout of GGCX, a VK-free diet, or depletion of VK by inhibiting VK epoxide reductase 1 with warfarin increased viral susceptibility in mice. Thus, we identified a MAVS regulatory mechanism-the existence of cytoplasmic protein carboxylation and topological inversion of GGCX-and demonstrated how modulating VK levels may influence antiviral defense.

Animals

Giant T wave inversion as a manifestation of asymmetrical apical hypertrophy (AAH) of the left ventricle. Echocardiographic and ultrasono-cardiotomographic study.

Left ventricular scanning by echocardiography and ultrasono-cardiotomography was performed to search the possible muscular abnormality in 9 cases with giant T wave inversion without documented cause. The deeply inverted T wave was more than 1.2 mV (average was 1.63 mV) in the left precordial leads. All the cases had electrocardiographic left ventricular hypertrophy of obscure origin and ischemic episode was absent. Conventional echo beam direction to measure the short axis of the left ventricle disclosed almost normal thickness and movement of both interventricular septum (IVS) and the posterior wasll (PW), so that the report of these cases is frequently within normal limits. However, ultrasono-cardiotomography (sector B scan) disclosed the fairly localized hypertrophy near the left ventricular apex, and conventional echocardiography also revealed the same area of either IVS or PW or both below the insertion of the papillary muscles, when the scanning towards the apex was performed (asymmetrical apical hypertrophy: AAH). Control study of 9 cases with IHSS showed asymmetrical septal hypertrophy (ASH) with almost equally hypertrophied IVS from base to apex. All cases had inverted T waves, but these were of lesser degree. Three cases had relatively deep T wave compatible with those of AAH, and these cases also had the apical hypertrophy of considerable degree (unusual type of IHSS, i.e., intermediate type between AAH and ASH). The close relationship between the depth of the inverted T waves and the Apex/Mid wall thickness ratios suggests that the altered recovery process of the hypertrophied apical musculature is responsible for the giant T wave inversion of heretofore unsolved origin. Until the connective link of AAH to the other forms of hypertrophic cardiomyopathy is disclosed, the cases with such a T wave and the apical hypertrophy may be designated as asymmetrical apical hypertrophy (AAH).

Adult

[An inverse reaction of the ST-T complex in the elctrocardiogram due to beta receptor inhibition].

In this article shall be referred to a special form of reaction of the ST-T-complexes in the propranolol test. Instead of a normalisation of this section of the ECG an inverse reaction develops. It consists in the fact that after application of propranolol the negativities of the T-waves increase and the lowerings of the ST-distances deepen. They appear most frequently after an acute heart attack, such as after a spontaneous angina pectoris, and they can be reproduced only during some days. It is supposed that the cooperation of acute ischaemic myocardial processes with negative sequelae of the blockade of beta-receptors are responsible for this inverse reaction.

Adrenergic beta-Antagonists

A new type of inversion of a human Y chromosome.

Using chromosome banding techniques, a phenotypically normal male was found to have an abnormal banding pattern of the Y chromosome. By the constitutive heterochromatin staining method, a darkly stained band was located on the short arm and the proximal region of the long arm. The quinacrine staining method also showed a similar abnormal banding pattern: a brightly fluorescing band was seen on the short arm and the proximal region of the long arm. By the conventional Giemsa staining method, however, no specific morphological abnormality was detected in the aberrant Y. On detailed karyotype analyses no recognizable abnormality of banding patterns of any other chromosome was found aside from the abnormal Y. The abnormality was determined to be a complex inversion of the Y chromosome, which is described as 46,X,inv(Y)(pter leads to p11::q11 leads to q12::cen::q12 leads to qter).

Aged

The chromosomes of four species of the nasuta complex of Drosophila. I. Chromosome maps and inversion polymorphism.

The salivary chromosomes of four species of the nasuta complex of Drosophila, D. sulfurigaster albostrigata, D, kohkoa, D. albomicans, and D. kepulauana were studied and chromosome maps of each species are presented; the maps of the latter three species are based on the map of D. sulfurigaster albostrigata. Three of the species D. sulfurigaster albostrigata, D. albomicans, and D. kohkoa were shown to be highly polymorphic for chromosomal inversions while the available evidence indicated that D. kepulauana is much less polymorphic. These facts are correlated with the geographic distribution of the species. Transitional homoselection has not been complete in the evolution of three of the species since D. sulfurigaster albostrigata, D. kohkoa, and D. albomicans have a number of naturally occurring polymorphisms in common.

Animals

Pericentric inversions of chromosome number 9: benign or harmful?

Pericentric inversions of chromosome number 9 have been studied in 4 different probands: a normal female with designation 46,XX,inv(9)(p12q13); a male with Down syndrome designated as 47,XY,+21,inv(9))p13q13); a premature infant with multiple, congenital malformations who was 46,XX,inv(9)(p12q21), and a Down syndrome proband with 47,XYqs,+21,inv(9)(p13q21). All 4 cases were shown to be inherited based on family studies. These families are discussed with reference to the literature as to what possible effect this structural change could have on the reproductive capability of a normal carrier and what guidelines are available for counseling such a carrier.

Abnormalities, Multiple

[Pericentric inversions: studies in 47 cases].

The authors report 47 cases of pericentric inversion. Eleven of them involve the chromosomes No. 2, 11 and 9. It appears that the risk of malformations and/or encephalopathy is obviously increased either by "position effect", aneusomie de recombinaison" or "interchromosomal effect". Prenatal diagnosis is therefore indicated. Thirty six cases involve the secondary constriction of chromosome No. 9. In such cases the risk is not enough increased to justify the prenatal diagnosis.

Brain

The polarity inversion of scalp potentials evoked by upper and lower half-field stimulus patterns: latency or surface distribution differences?

Evoked potentials to patterned stimulation of the upper and lower half of the visual field are generally inverted in polarity. Two conflicting proposals have been made to explain this effect, both based on surface distribution studies of pattern-reversal and/or pattern-onset VEPs. The first suggests that this polarity inversion is due to differences in surface distribution of corresponding components of constant latency; the second that it is due to differences in the latencies of peaks of similar surface distributions in the upper and lower half-field responses. Experimental evidence is here presented which supports the first explanation for the case of the pattern-onset VEPs. These results, which illustrate how different components in the same response can be identified from the selective adaptation effects of pre-exposure to outline patterns, show that there is no difference in latency of components of corresponding properties in the upper and lower half-field VEPs.

Electroencephalography

Fractures are highly correlated with bone density and inversely correlated with bone turnover markers in autosomal dominant osteopetrosis.

Autosomal dominant osteopetrosis (ADO) is a rare osteosclerotic disorder usually caused by missense variants in the CLCN7 gene, which results in impaired osteoclastic bone resorption. Penetrance is incomplete, and disease severity varies widely, even among relatives within the same family. Although ADO can cause visual loss, osteonecrosis, osteomyelitis, and bone marrow failure, the most common complication of ADO is fracture. We are conducting a natural history study to characterize disease progression and determinants of disease severity. We hypothesized that baseline BMD and bone turnover markers would correlate with self-reported fracture history. We report cross-sectional analysis of baseline data from the natural history study in 54 individuals (42 adults, 12 children). In adults, Z-scores for both volumetric (r&#xa0;=&#x2009;0.87, p&#xa0;<&#x2009;.001) and areal BMD (aBMD) of the LS, and Z-scores for FN, and TH aBMD (r&#xa0;=&#x2009;0.77 to 0.78; p&#xa0;<&#x2009;.001) were correlated with lifetime fracture number. Tartrate resistant acid phosphatase, a marker of osteoclast number, correlated positively with fracture (r&#xa0;=&#x2009;0.52, p&#xa0;=&#x2009;.004) consistent with an adaptive response of higher numbers of osteoclasts among more severely affected individuals. However, fracture number correlated inversely with the bone resorption markers serum C-telopeptide (r&#xa0;=&#x2009;-0.60, p&#xa0;<&#x2009;.001) and urine N-telopeptide/creatinine ratio (r&#xa0;=&#x2009;-0.35, p&#xa0;=&#x2009;.047), suggesting that ADO subjects who have the most reduced osteoclast activity have a greater tendency to fracture. Correlation coefficients between fractures, BMD, and bone turnover markers were similar when limited to the 37 adults with disease-causing CLCN7 variants. There were no statistically significant differences between subjects with the most common CLCN7 variant (G215R), the most common variant in our cohort, compared to other CLCN7 variants with respect to fracture, bone density measures, or biochemical markers of bone turnover. These data demonstrate that bone density and biochemical bone turnover markers are indicators of ADO severity as defined by fracture number.

Humans

A partial denaturation map of herpes simplex virus type 1 DNA: evidence for inversions of the unique DNA regions.

Partial denaturation maps of 30 HSV-I DNA molecules have been obtained using a procedure designed to avoid possible hydrolysis of the DNA at alkalilabile bonds. From the denaturation pattern of the long unique DNA region these molecules were divided into two groups comprised of 16 and 14 molecules. Histogram plots relating the precentage denaturation to position on the DNA for these two groups were aligned in a manner appropriate to the HSV-I genome model. It was apparent that these groups had the orientation of the long region inverted with respect to each other. Similarly, from the denaturation maps of the short unique region, the molecules were divided into two groups each comprising 15 molecules. Alignment of the histogram plots of these groups indicated that the orientation of the short region was inverted in one group relative to the other. These partial denaturation data confirm the presence of four HSV-I genome arrangements resulting from the possible combinations of inversions of the two unique DNA regions.

DNA, Viral

Serum inorganic phosphate in middle-aged men. I. Inverse relation to body weight.

Serum inorganic phosphate was determined in 752 men born in 1926. An inverse correlation was found between serum inorganic phosphate levels and body weight. Other parameters of possible relevance to this finding, such as serum calcium, serum albumin, serum lambda-glutamyltransferase, and the occurrence of upper gastrointestinal disorders were analysed, and no correlations to the phosphate level were detected.

Age Factors

Cerebellar stimulation in alumina-gel monkey model: inverse relationship between clinical seizures and EEG interictal bursts.

The efficacy of cerebellar stimulation was addressed in a chronic monkey model (N = 12) of spontaneous focal motor and secondarily generalized seizures using 24 hr seizure frequency monitoring and all-night EEG recording. The anterior cerebellar vermis was stimulated employing parameters similar to those used in man, 10 Hz, 1 msec pulses, 10 min on, 10 off, at an average current of 2.0 mA. Six weeks pre- and post-base-line periods were compared to a stimulation period of the same length. The results contribute to a clarification of conflicting findings of previous researchers by revealing an inverse relationship between seizure frequency and interictal EEG bursts during the weeks of stimulation. Seizure frequency increased significantly and interictal bursts decreased. Both of these effects (especially the former) were evident in the post-stimulation period, but for different reasons than hypothesized for the period of stimulation. Whereas the therapeutic value of cerebellar stimulation on seizures may be in question, its utilization in the study of mechanisms of epilepsy may be warranted.

Animals

Sequence arrangement in herpes simplex virus type 1 DNA: identification of terminal fragments in restriction endonuclease digests and evidence for inversions in redundant and unique sequences.

It has been proposed by Sheldrick and Berthelot (1974) that the terminal sequences of herpes simplex virus type 1 (HSV-1) DNA are repeated in an internal inverted form and that the inverted redundant sequences delimit and separate two unique sequences, S and L. In this study the sequence arrangement in HSV-1 DNA has been investigated with restriction endonuclease cleavage, end-labeling studies, and molecular hybridization experiments. The terminal fragments in digests with restriction endonucleases Hind III, Hpa-1, EcoRI and Bum were identified and shown to be consistent with the Sheldrick and Berthelot model. Inverted fragments which contain unique sequences as well as redundant sequences, and which the model predicts, were identified by DNA-DNA hybridization studies. Further cleavage of Bum fragments with Hpa-1 also revealed inversions of the terminal sequences that contained unique sequences. The results obtained showed that the unique sequences S and L are relatively inverted in different DNA molecules in the population, resulting in the presence of four related genomes with rearranged sequences in apparently equal amounts. The redundant sequences bounding S do not share complete sequence homology with those bounding L, but hybridization studies are presented which show that the terminal 0.3% of the genome is repeated in every redundant sequence.

Base Sequence

The inverse compensating filter.

When a single-field technique is used in megavoltage x-ray therapy, a uniform entrance dose is often required. If there is a large variation in source-to-surface distance over the field, an inverse type of compensating filter is necessary to achieve entrance dose uniformity. The production and utilization of these filters is discussed.

Filtration