Arginine vasopressin potentiates inspiratory bursting in hypoglossal motoneurons of neonatal mice.

Vasopressin (AVP) acts as a neurotransmitter and its activity can potentiate respiratory activity. Hypoglossal (XII) motoneurons that innervate the tongue express V1a vasopressin receptors, which are excitatory. Therefore, we hypothesized that V1a receptor activation at XII motoneurons would potentiate inspiratory bursting. We developed this study to determine whether AVP can potentiate inspiratory bursting in rhythmic medullary slice preparations in neonatal (postnatal, P0-5) mice. Bath or local application of AVP potentiated inspiratory bursting compared to baseline XII inspiratory burst amplitude. Antagonizing V1a receptors revealed significant attenuation of the AVP-mediated potentiation of inspiratory bursting, while antagonism of oxytocin receptors (at which AVP has similar binding affinity) revealed a trend to attenuate AVP-mediated potentiation of inspiratory bursting. Finally, we discovered that the AVP-mediated potentiation of inspiratory bursting increases significantly with postnatal maturation from P0-5. Overall, these data support that AVP potentiates inspiratory bursting directly at XII motoneurons.

Co-expression of Hif1alpha and CAIX is associated with poor prognosis in oral squamous cell carcinoma patients.

BACKGROUND: This study investigates the prognostic impact of the expression of hypoxia-inducible factor 1alpha (Hif1alpha) and carbonic anhydrase IX (CAIX) detected by immunohistochemistry in oral squamous cell carcinoma (OSCC). METHODS: Statistical analysis of immunohistochemical results with clinical parameters including survival outcomes was performed for 80 OSCC patients. RESULTS: Patients with a low expression of both proteins survived on average 54.8 months, whereas those with an increased expression of Hif1alpha in their tumors combined with a low expression of CAIX survived on average only 37.6 months (P = 0.026). In multivariate Cox's regression hazard analysis, again patients with a low expression of Hif1alpha/CAIX had the best prognosis, whereas patients with increased Hif1alpha and low CAIX expression carried a 4.97-fold increased risk of tumor-related death (P = 0.042). CONCLUSION: A co-detection of low Hif1alpha/CAIX expression is significantly correlated with a better prognosis for OSCC patients, which may have implications for therapy options for these patients.

Pilomatrixoma: diagnóstico ecotomográfico / Pilomatrixoma: ultrasound diagnosis

BACKGROUND: Pilomatrixoma is a benign tumor of the skin, preferentially found in children. The final diagnosis is made by biopsy. High resolution ultrasound (US) is a non invasive method for its diagnosis. AIM: To describe the US findings in children with pilomatrixoma. MATERIAL AND METHODS: Fifty five patients with 62 clinically suspected pilomatrixomas were studied by US. All examinations were done with an ATL HDI 5000, linear 5-12 MHz transducer. Pathological study confirmed the diagnosis pilomatrixoma in 52 cases. RESULTS: Fifty of 52 pilomatrixomas were diagnosed by US, with a sensitivity of 96 per cent. The mean age of patients was 7.5 years. Forty seven lesions (90 per cent) were located in the head, neck or upper extremities and their mean size was 8.5 mm. Thirty two lesions were hypodermal, 14 were dermohypodermal and 6 were dermal. In 44 lesions the contour was regular and non delineated, 44 lesions were oval, 41 lesions had an acoustic shadow, 36 were echogenic or hyperechogenic, 31 had a peripheral halo (60 per cent), 55 had calcifications (98 per cent), nine had perilesional vessels, 2 had intratumoral vessels and 7 had inflammatory changes. US excluded the diagnosis of pilomatrixoma in 10 lesions formulating a correct differential diagnosis in eight, with a specificity of 80 per cent. CONCLUSIONS: Pilomatrixomas had two US types of presentation. The first is a well defined nodule with peripheral halo partially calcified or with microcalcifications. The second is a completely calcified nodule without peripheral halo and with a strong acoustic shadow. US is a useful, sensitive and specific diagnostic method for pilomatrixoma.

A high frequency of tumors with rearrangements of genes of the HMGI(Y) family in a series of 191 pulmonary chondroid hamartomas.

Pulmonary chondroid hamartomas (PCHs) are benign mesenchymal tumors that often are characterized by specific chromosomal aberrations. Herein we report our cytogenetic and molecular cytogenetic (FISH) studies on 191 PCHs, including 48 previously published cases. In this series, 134/191 PCHs (70.2%) showed either abnormalities of chromosomal bands 6p21 (21 tumors), 12q14-15 (95 tumors), or had other abnormalities (18 tumors). Two tumors had a 6p21 aberration together with a 12q14-15 aberration. The most frequent translocations were t(12;14)(q15;q24) (19 cases) and t(6;14)(p21. 3;q24) (18 cases), both in either simple or complex form. By FISH with cosmids spanning the gene encoding the high-mobility-group protein HMGIC, we were able to show a rearrangement within or close to HMGIC in all tumors with 12q14-15 abnormalities tested, in 11 tumors with an apparently normal karyotype, and in 4 tumors with complex abnormalities without cytogenetically visible alterations of chromosomes 12. Rearrangements of HMGIY or its immediate surroundings were shown for 21 cases with 6p21 aberrations and three cases with other chromosomal abnormalities but without cytogenetically visible alterations of chromosomes 6. Genes Chromosomes Cancer 26:125-133, 1999.

HMG1 is not rearranged by 13q12 aberrations in lipomas.

Several cytogenetic subgroups with characteristic lesions involving chromosomal regions 12q14-15, 6p21.3, or 13q12 can be distinguished in lipomas. Rearrangements of the HMGIC gene have been described in cases with 12q14-15 abnormalities, whereas HMGIY has been shown to be the target gene of 6p21.3 aberrations. Recently, HMG1, another member of the HMG family, was mapped to 13q12. The aim of this study was to investigate the possible role of HMG1 aberrations in lipomas with 13q12 abnormalities. Two PAC clones containing HMG1 were isolated. By molecular cytogenetic investigations using these PAC clones and by Southern blot analysis of eight lipomas with 13q12 abnormalities, we were able to show that these chromosomal rearrangements did not result in intragenic rearrangements of HMG1 or breakpoints close to it.

Pleomorphic adenomas of the salivary glands: absence of HMGIY rearrangements.

Rearrangements of chromosome region 12q14-15 affecting the HMGIC gene are a frequent finding in benign solid tumors. Another non-random chromosomal alteration observed in subgroups of several of the tumor entities with 12q14-15 changes are rearrangements of 6p21 resulting in alterations of the HMGIY gene, which have so far not been documented in pleomorphic adenomas of the salivary glands. In our series of 335 pleomorphic adenomas, karyotypic changes affecting chromosomal region 6p21-23 were observed in five tumors all showing either a simple or complex t(6;8)(p21-p23;q12). Molecular cytogenetic studies of two of these tumors revealed that the 6p-breakpoint of this translocation maps distal to HMGIY, not affecting the gene or its closer vicinity. The results strongly suggest that pleomorphic adenomas are the only exception to the rule that entities of benign tumors with HMGIC rearrangements also have subtypes with HMGIY rearrangements. The difference from the other tumors is discussed in terms of tissue specificity of both HMG protein genes.

Cervical electromyographic activity during low-speed rear impact.

Whiplash motion of the neck is characterized by having an extension-flexion motion of the neck. It has been previously assumed that muscles do not play a role in the injury. Eight healthy males were seated in a car seat mounted on a sled. The sled was accelerated by a spring mechanism. Muscle electromyographic (EMG) activity was measured by wire electrodes in semi-spinalis capitis, splenius capitis, and levator scapulae. Surface EMG activity was measured over trapezius and sternocleidomastoideus. Wavelet analysis was used to establish the onset of muscle activity with respect to sled movement. Shorter reaction times were found to be as low as 13.2 ms from head acceleration and 65.6 ms from sled acceleration. Thus the muscles could influence the injury pattern. It is of interest that clinical symptoms are often attributed to muscle tendon injuries.

The t(3;12)(q27;q14-q15) with underlying HMGIC-LPP fusion is not determining an adipocytic phenotype.

The HMGIC gene, located in chromosome band 12q15, is rearranged in many different benign human tumors, often resulting in its fusion to ectopic sequences from other genes. The t(3;12)(q27;q14-q15) fuses HMGIC with the LPP gene and has so far been described exclusively in lipomas. Thus, it can be hypothesized that this particular gene fusion determines the adipocytic differentiation. We studied five pulmonary chondroid hamartomas all showing a t(3;12)(q27;q14-q15) that apparently was identical to the one observed in lipomas. By fluorescence in situ hybridization we found that both HMGIC and LPP are disrupted by this translocation. By RT-PCR the existence of a HMGIC/LPP fusion gene was confirmed. These results show that the fusion is not specific for lipomas. We favor the hypothesis that it is an ectopic sequence fused to HMGIC that is responsible for a cell shift to an embryogenic stage. Following this hypothesis the phenotype of the tumor may be induced by extracellular signal transduction.

Mapping and molecular characterization of five HMG1-related DNA sequences.

Recently, the high mobility group (HMG) proteins have attracted a lot of interest since it was shown that some members of that group can causally be involved in tumorigenesis. One HMG protein gene member is HMG1 for which the number of related DNA sequences has been estimated to be approximately 20-30. Nevertheless, besides the gene for HMG1 only one retropseudogene has been molecularly characterized. It was the aim of this study to map and characterize further sequences related to HMG1. PCR-screening of a PAC library resulted in 25 very strongly positive clones apparently containing HMG1-like cDNA sequences. Of eight clones which were further investigated five were distinguishable from each other based on their chromosome assignment and DNA sequence. Due to their homology to the HMG1 gene the DNA sequences were designated as HMG1L1, HMG1L3, HMG1L4, HMG1L5, and HMG1L6. By FISH experiments they were assigned to 2q32, 2q35, 3p24, 15q22, and 20q13, respectively. Except for one sequence, they did not show mutations leading to a frame shift or a new termination codon. Thus, we cannot exclude that these four HMG1-related DNA sequences represent active genes or can at least be activated e.g. by chromosome rearrangements in tumor cells. So far, the existence of six genes encoding HMG proteins has been described but because of a high frequency of closely related DNA sequences in the human genome it can be assumed that some of them are either pseudogenes or very similar genes.

Study provides new evidence of back belts' effectiveness.

A major new study conducted by the UCLA School of Public Health has bolstered the claim that back support devices reduce low-back injuries. The study involved nearly 36,000 employees at Home Depot stores in California who logged 101 million work hours from 1989 through 1994. The company implemented mandatory wearing of belts in early 1990, and the study's authors reported that the workers' rate of acute low back injuries fell from 30.6 per million hours before implementation to 20.2 per million hours. UCLA Professor of Epidemiology Jess F. Kraus, the study's lead author, told The Wall Street Journal. "The study found a pretty big effect with a simple countermeasure. It is pretty hard to argue that it is a chance phenomenon." Kraus, who is the director of UCLA's Southern California injury Prevention Research Center, began his research by visiting 30 Home Depot stores to see whether employees were wearing the belts consistently. Compliance with the mandatory policy was quite high overall-above 98 percent, as calculated during an unannounced walk-through of all 77 stores in late 1993 and early 1994, according to the study. Back support manufactures hailed the Home Depot study as the largest long-term epidemiological study yet undertaken of the supports. It is proof, they said, that back supports are effective personal protective equipment-a contention at odds with the position of NIOSH the National institute for Occupational Safety and Health. In 1994, NIOSH reviewed the scientific literature and concluded there was not enough evidence to recommend that the supports be worn by uninjured workers. Sales plunged after NIOSH released its findings, according to the manufactures. The UCLA researchers found that low-back injuries declined in workers of both sexes, in younger workers as well as those older than 55, and among those with low levels of lifting as well as those with higher levels. The researchers concluded that mandatory use of back supports significantly reduces acute low-back work injuries. Low-back injuries account for one-fourth of all workers' compensation claims paid by U.S. employers-$11 billion in 1990 alone. NIOSH's ergonomic coordinator, Lawrence Fine, told The Journal, "for many companies this is the largest health and safety issue they are wrestling with." NIOSH has embarked on its own, smaller study of back supports' effectiveness among Wal-Mart workers.

Transcriptional activation of HMGI-C in three pulmonary hamartomas each with a der(14)t(12;14) as the sole cytogenetic abnormality.

Aberrations involving the chromosomal region 12q14-15 are non-random cytogenetic abnormalities in many benign tumors, e.g. pulmonary chondroid hamartomas (PCH). Recently, we identified rearrangements of the HMGI-C gene within the third or fourth intron as the molecular mechanism underlying most of these chromosomal aberrations. Herein we report our FISH and RACE studies on three PCHs each showing a rare variant type of the translocation t(12;14)(q14-15;q24) with presence of two normal chromosomes 12 and a der(14) but missing the der(12). The results revealed that in all three cases the breakpoint is located 5' to HMGI-C, suggesting that besides intragenic rearrangements also transcriptional activation of the gene can initiate tumor growth.

HMGI-C rearrangements as the molecular basis for the majority of pulmonary chondroid hamartomas: a survey of 30 tumors.

Pulmonary chondroid hamartomas (PCH) are benign tumors of the lung characterized by a more or less high degree of mesenchymal metaplasia. In our series we investigated 30 PCH by a combination of cytogenetic and molecular methods. 18 tumors (60%) had cytogenetically detectable aberrations involving either 12q14-15 or 6p21 with a clear predominance of chromosomal abnormalities involving 12q14-15 (15 tumors). As in subgroups of pleomorphic adenomas of the salivary glands, leiomyomas of the uterus, and lipomas with 12q14-15 abnormalities the HMGI-C gene is frequently rearranged we tested PCH with either 12q14-15 abnormalities or normal karyotype by FISH and 3' RACE experiments for rearrangements of HMGI-C. Rearrangements were found in all cases with chromosomal 12q14-15 abnormalities and further six cases with an apparently normal karyotype. By the combination of cytogenetics with molecular techniques the percentage of cases with intragenic rearrangements of HMGI-C or rearrangements of its immediate surrounding was thus increased to 70% (21/30 cases). Considering all types of aberrations within this series 80% (24/30) of all PCH were aberrant. This is the first report on a combined molecular and cytogenetic analysis of a large series of pulmonary chondroid hamartomas indicating that rearrangements of HMGI-C, a member of the high mobility group protein gene family, are the leading molecular events in the genesis of PCH.

Cytogenic and molecular analysis of an aggressive angiomyxoma.

Aggressive angiomyxoma is a rare mesenchymal tumor occurring mainly in the vulvar region extending into the paravaginal and perirectal region. Histologically, this tumor is rich in vascular structures and in collagen fibers and is of myxoid appearance. Cytogenetic and molecular analysis was performed on a case of an aggressive angiomyxoma and revealed clonal karyotypic abnormalities. All 50 metaphases analyzed showed a translocation involving the chromosomal region 12q14-15. Chromosomal aberrations involving the breakpoint region 12q14-15 are frequently seen in a variety of other mesenchymal tumors as uterine leiomyomas, lipomas, hamartomas of the lung, liposarcomas, or hemangiopericytomas. Therefore, this breakpoint region seems to be the most frequent chromosomal abnormality associated with the initiation of human mesenchymal neoplasms. To narrow down the breakpoint region on a molecular level in the cells of the angiomyxoma we performed FISH analysis with different cosmid clones originating from a yeast artificial chromosome and cosmid contig overspanning parts of the region 12q14-15. We were able to narrow down the region to approximately 70-80 kb belonging to an area designated a multiple aberration region, because it also includes the breakpoints of leiomyomas, lipomas, and pleomorphic adenomas with 12q13-15 abnormalities. Our molecular and cytogenic data suggest that angiomyxomas or at least a subset of them molecularly belong to the benign group of mesenchymal tumors showing multiple aberration region involvement.

Molecular characterization of 12q14-15 rearrangements in three pulmonary chondroid hamartomas.

Chromosomal aberrations involving the chromosomal breakpoint region 12q14-15 are frequently seen in a variety of mesenchymal tumors as uterine leiomyomas, lipomas, myxoid liposarcomas, enchondromas, or hemangiopericytomas. Therefore, this breakpoint region seems to be one of the most frequent chromosomal abnormality associated with the initiation of human mesenchymal neoplasms. To narrow down the breakpoint region on a molecular level in cells of three pulmonary chondroid hamartomas with 12q14-15 aberrations, we performed fluorescence in situ hybridization analysis with different cosmid clones originating from a YAC and cosmid contig overspanning parts of the region 12q14-15. We were able to narrow down the breakpoint to a region of 175 kb belonging to an area designated multiple aberration region because it also includes the breakpoints of leiomyomas, lipomas, and pleomorphic adenomas with 12q14-15 abnormalities. Our molecular and cytogenetic data suggest that hamartomas of the lung molecularly belong to the benign group of mesenchymal tumors showing multiple aberration region involvement.

Trisomy 8 and 18 as frequent clonal and single-cell aberrations in 185 primary breast carcinomas.

For cytogenetic investigations short-term cultures of 185 breast carcinomas (135 invasive ductal, 21 invasive lobular, 12 invasive ductal with intraductal components, seven heterogeneous, six intraductal, four invasive ductal and lobular) were prepared. Cytogenetic examinations revealed clonal abnormalities in 39 cases with a predominance of simple numerical chromosome changes, i.e., trisomies of chromosomes 7, 8, and 18. One hundred forty-six tumors did not show clonal abnormalities, but single-cell aberrations other than monosomies occurred in 79 of these tumors. Compared to cells of epithelial hyperplasia of the breast, amniotic fluid cells, and cells from pleomorphic adenomas cultivated using the same medium, the frequency of single-cell trisomies was significantly higher. Trisomy 8 was not only found as a clonal aberration in 10 cases but was also the most frequent non-clonal aberration. Trisomy 7 and 18 were also frequent clonal as well as non-clonal cytogenetic deviations.

Fibroadenoma of the breast showing a translocation (6;14), a ring chromosome and two markers involving parts of chromosome 11.

The cytogenetic findings of a recurrent fibroadenoma of a 25-year-old woman are reported. Of 58 metaphases karyotyped after G-banding, 27 showed an apparently normal karyotype and 31 the karyotype 48,XX,del(6)(q21),r(11)(?) + der(11)x2,der(14)t(6;14)(q21;q32). By fluorescence in situ hybridization studies using a chromosome 11 specific painting probe, we were able to show that the two marker chromosomes and the ring contained chromosome 11 DNA.

Cytogenetic subtyping of 220 salivary gland pleomorphic adenomas: correlation to occurrence, histological subtype, and in vitro cellular behavior.

Based on the hypothesis that three main cytogenetic subtypes of salivary gland pleomorphic adenomas can be distinguished which may also represent different etiologic entities, we investigated whether these subtypes correspond to clinical, histologic, or biologic features of 220 tumors karyotyped (including 117 tumors with detailed clinical history and histologic subtyping). The following results were obtained. As compared with the group of patients showing salivary gland pleomorphic adenomas with an apparently normal karyotype, the patients in the "8q12-group" were significantly younger (51.1 years versus 39.3 years, p < 0.001). The distribution of histologic subtypes also showed highly significant differences between the groups. Whereas the breakpoint in the 8q12 group was always mapped to a single band, no exact localization of the breakpoint in the group of tumors showing chromosome number 12 abnormalities was possible. In most cases, however, the breakpoints were clustered to 12q15. Finally, all tumors with 8q12 breakpoints showed a characteristic in vitro cellular morphology which was also observed in a few tumors with an apparently normal karyotype but in none of the tumors with the 12q13-15 breakpoint.

Expression of SV40 T-antigen in lipoma cells with a chromosomal translocation T(3;12) is not sufficient for direct immortalization.

12q13-15 changes are the most frequent cytogenetic abnormalities in human tumor cells. To test their biological significance we used an assay based on lipoma cells with a limited in vitro lifetime and this type of chromosomal aberration. Lipoma cells with a reciprocal translocation t(3;12)(q28;q14) were transformed by transfection with a plasmid containing the SV40 "early region". The transformed cells showed an altered morphology with loss of contact inhibition, formation of foci, and T-antigen expression. They were immortalized after a growth crisis. The karyotypic patterns before and after the crisis show that the translocation together with expression of SV40 T-antigen is not sufficient for direct immortalization.