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PubMed2006

Holoprosencephaly-like phenotype: clinical and genetic perspectives.

We report 22 patients with normal neuropsychological development and a holoprosencephaly-like (HPE-like) phenotype screened for SHH, SIX3, TGIF, and GLI2. These patients were divided into two groups: (1) 6 patients with SHH and GLI2 mutations and (2) 16 patients with no detectable mutations. We discuss the phenotypic manifestations, evolution of the phenotype, and neuroimaging in the two groups. Conclusions about the HPE-like phenotype include (1) initial appearance as an unusually wide, and very severe unilateral cleft lip-palate in some cases; (2) variability with the expression of minor anomalies in some cases, such as single maxillary central incisor; (3) identifiable mutations in some cases and absence of mutations in others; (4) essentially normal MRI in the most cases (pituitary tumor in two cases and choroid fissure cyst in one case in Group 1; empty sella turcica in one case in Group 2); (5) intelligence within the normal range; and (6) familial aggregation in some instances. Implications include (1) thorough examination of family members for minor anomalies; (2) MRI and developmental assessment for the proband; and (3) molecular analysis.

Abnormalities, Multiple↗
PubMed1986

Organization and chromosomal distribution of a novel repetitive DNA component from Muntiacus muntjak vaginalis with a repeat length of more than 40 kb.

The organization and chromosomal distribution of the repetitive DNA component IB from Muntiacus muntjak vaginalis (MMV) was investigated. DNA fragments of component IB were cloned in cosmids and their structure analysed using restriction nucleases and blot-hybridization experiments. Two cosmids were found to be practically identical by restriction enzyme mapping. The repeat unit of component IB DNA is more than 40 kb and contains the 11 and 18 kb Bam HI fragments, which have previously been shown to cross-hybridize with MMV satellite IA. In addition, the repeat unit contains long stretches of DNA sequences which are unique to component IB. In situ hybridization experiments showed that component IB has the properties characteristic of long interspersed repetitive DNA rather than tandemly repeated satellite DNA. Consistent with this conclusion, only a minor fraction of component IB is located on the X chromosome as demonstrated by the analysis of somatic cell hybrids. This is in marked contrast to satellite IA that is specific for the X chromosome. These results have interesting implications for the evolution of the component I DNA family of the MMV genome.

Animals↗
PubMed1998

Phylogenetic analyses of the matrix and non-structural genes of equine influenza viruses.

Matrix (M) and nonstructural (NS) genes of thirteen equine H3N8 and H7N7 influenza viruses were sequenced and analyzed from an evolutionary point of view. The M and NS genes of H3N8 viruses isolated between 1989 and 1993 evolved into two minor branch clusters, including isolates from Europe and the American continent, respectively. It was noteworthy to reveal that the nucleotide sequences of the M and NS genes of an earlier American strain showed highest homology to those of recent European viruses. "Frozen evolution" was observed in the M and NS genes of A/eq/LaPlata/1/88. It was also evident that the NS gene of an H7N7 virus from 1977 was very similar to that of a 1979-H3N8 virus, while the M gene was closest phylogenetically to that of the earliest H7N7 virus isolated in 1956. Furthermore, the M2 protein of A/eq/Newmarket/1/77 virus contained a carboxyl terminal deletion of three amino acids. The evolutionary rates of the M and NS genes of H3N8 equine influenza viruses were estimated to be 5.4 x 10(-4) and 5.1 x 10(-4) substitutions per site per year, respectively, which were slower than those of human viruses.

Amino Acid Sequence↗
PubMed2006

[Evaluation and treatment of kidney penetrating wounds].

Penetrating lesions of the kidney are less frequent than closed wounds. However, their incidence has increased these past decades, in relation with the augmentation of urban violence. The main causes of penetrating wounds are knives and firearms, with a related rate of renal lesions more important in the second case. The treatment of renal traumas has evolved these past years. Previously, surgical investigations were systematically indicated in most cases, which was associated with an elevated number of nephrectomies. Today, the development of new diagnostic imaging techniques available in most emergency units allows in certain cases the replacement of therapy by a strict follow-up of the patient, the objective being to preserve the kidney. The principal diagnostic investigation is CT scanning with injection of a contrast product, which is useful to adequately classify renal lesions and to make decision regarding the best first-line therapeutic management. In case of penetrating lesion, the first step is the evaluation of the haemodynamic condition of the patient. In case of haemodynamic instability, immediate surgical investigation is necessary. Conversely, if the patient is stable, CT with delayed imaging must be carried out. For grade I and II renal lesions, therapeutic abstention is recommended. Grade III and IV lesions associated with other intraperitoneal lesions that require emergency laparotomy must be surgically investigated and in these cases, reconstructive surgery or nephrectomy must be considered. Most grade IV lesions associated with a lesion of the renal hilus and grade V lesions must be referred to surgery. Minor renal lesions may not be treated; such cases necessitate a follow-up of the patient that should include successive assessments of the haemoglobin and the haematocrite, together with CT and ultrasonographic investigations aimed at the follow-up of lesion evolution and detection of potential urinomas or prolonged bleedings. The progressive decrease of the haematocrite and arteriovenous fistulae must be treated first by an embolization. Untreated patients with persistent urinary fistulae will undergo, if necessary, ureteral catheterization and percutaneous drainage of the urinoma.

Algorithms↗
PubMedDate not supplied

The crossmatch. A brief historical perspective.

First described in 1907, the crossmatch has been in a constant state of modification since that time. Major milestones in the evolution of the test include demonstration of the relative importance of red blood cell typing and of the matching test, development of rapid techniques for the test, advent of high protein, antiglobulin and enzyme techniques, and resolution of issues related to the minor crossmatch and the need for complement in the test.

Animals↗
PubMed2004

Recent origin and phylogenetic utility of divergent ITS putative pseudogenes: a case study from Naucleeae (Rubiaceae).

The internal transcribed spacer (ITS) of nuclear ribosomal DNA has been widely used by systematists for reconstructing phylogenies of closely related taxa. Although the occurrence of ITS putative pseudogenes is well documented for many groups of animals and plants, the potential utility of these pseudogenes in phylogenetic analyses has often been underestimated or even ignored in part because of deletions that make unambiguous alignment difficult. In addition, long branches often can lead to spurious relationships, particularly in parsimony analyses. We have discovered unusually high levels of ITS polymorphism (up to 30%, 40%, and 14%, respectively) in three tropical tree species of the coffee family (Rubiaceae), Adinauclea fagifolia, Haldina cordifolia, and Mitragyna rubrostipulata. Both secondary structure stability and patterns of nucleotide substitutions in a highly conserved region (5.8S gene) were used for distinguishing presumed functional sequences from putative pseudogenes. The combination of both criteria was the most powerful approach. The sequences from A. fagifolia appear to be a mix of functional genes and highly distinct putative pseudogenes, whereas those from H. cordifolia and M. rubrostipulata were identified as putative pseudogenes. We explored the potential utility of the identified putative pseudogenes in the phylogenetic analyses of Naucleeae sensu lato. Both Bayesian and parsimony trees identified the same monophyletic groups and indicated that the polymorphisms do not transcend species boundaries, implying that they do not predate the divergence of these three species. The resulting trees are similar to those produced by previous analyses of chloroplast genes. In contrast to results of previous studies therefore, divergent putative pseudogenes can be useful for phylogenetic analyses, especially when no sequences of their functional counterparts are available. Our studies clearly show that ITS polymorphism may not necessarily mislead phylogenetic inference. Despite using many different PCR conditions (different primers, higher denaturing temperatures, and absence or presence of DMSO and BSA-TMACl), we recovered only a few functional ITS copies from A. fagifolia and none from H. cordifolia and M. rubrostipulata, which suggests that PCR selection is occurring and/or the presumed functional alleles are located at minor loci (with few ribosomal DNA copies).

Base Composition↗
PubMed1984

The neuropathology of kernicterus in the premature neonate: diagnostic problems.

Yellow staining of central nervous system (CNS) nuclei occurs in the brains of some neonates, despite low levels of serum bilirubin. Two conditions appear to be important in the evolution of this form of kernicterus: prematurity and asphyxia. In a seven year retrospective study of a large neonatal autopsy population, 102 cases had kernicterus as indicated by selective macroscopic yellow staining and microscopic damage within specific CNS nuclei. Neuropathological study disclosed minor variations and numerous similarities in the manifestations of kernicterus in the asphyctic premature neonate with low levels of serum bilirubin, as compared to kernicterus in the full-term neonate with high levels of serum bilirubin. Acidosis, hypoxia, hyperoxia, hypothermia and sepsis have been considered significant risk factors, but recent comparative clinical studies have not defined predictive indices. Analysis of this disorder is difficult because of the concurrence of other complications of asphyxia and its pathological correlates in premature infants. Diagnostic difficulties are also compounded by variations in the definitions of kernicterus as used by different investigators.

Asphyxia Neonatorum↗
PubMed1990

From women in white to scholarship: the new nurse leaders in Thailand.

The nature of nursing in Thailand has changed dramatically since World War II. The field is now led by a cadre of women who make nursing one of the largest occupational concentrations of women who hold doctoral degrees in the country. In this article reflections of these nurses on their profession, on their reasons for entering it, and on their contributions to it's development are discussed. The findings are derived from a survey of 16 nurses with doctoral degrees and from participant observation. The women and their parents who guided their choice of a career were attracted to nursing by ideals of social service and family obligations. They were also attracted to nursing by its cultural definition as a female career and by the pragmatics of university entrance examinations. Most of the informants attributed their career success to hard work, family support, a strong sense of responsibility and commitment, self-sacrifice for the common good, and a calm demeanor. A minority of informants stressed new values of scholarship and management skills such as long-range planning and independent thinking. The emergence of these new values suggests that nursing in Thailand is on the verge of a new stage in its rapid evolution.

Adult↗
PubMed1999

Evolution of remission as the new standard in the treatment of depression.

Epidemiologic and clinical data support the goal of treating depressed patients to wellness or full remission. Many patients improve but fail to achieve full remission with antidepressant treatment and continue to have residual symptoms, which cause distress and dysfunction. These residual symptoms may meet criteria for subsyndromal and minor depression. Patients who have these milder syndromes after treatment have a greater risk of relapse and recurrence than do those who remain symptom-free. Clinical trials of antidepressants have shown lower rates of remission than of responses that fall short of remission, although some dual-acting antidepressants (e.g., serotonin-norepinephrine reuptake inhibitors) may have higher remission rates than other agents. Treatment with such robust dual-acting antidepressants may result in higher rates of remission and fewer residual symptoms than treatment with selective serotonin reuptake inhibitors.

Antidepressive Agents↗
PubMed1982

Minor early embryonic chick hemoglobin M. Amino acid sequences of the epsilon and alpha D chains.

Erythrocytes of the early chick embryo contain four hemoglobins, two major and two minor. In this paper, we present amino acid sequences for the beta-like and alpha-like chains of HbM, the least abundant of the four early chick hemoglobins. The complete amino acid sequence of the beta-like chain of HbM is identical with that of the epsilon chain of HbE, the other minor early embryonic hemoglobin in the domestic chicken. Analysis of the alpha-like chain of HbM (92 of 141 residues) reveals a globin sequence closely related to the minor adult alpha D chain. Comparison of our sequence data with the nucleotide sequence of the alpha D globin gene suggests that a single gene encodes both the embryonic and adult alpha D globin polypeptides. We discuss the structure, possible function, and evolution of the HbM globin chains.

Amino Acid Sequence↗
PubMed1978

[Phlebectasia of the internal jugular vein post injury (author's transl)].

The authors present the case of a 14 year-old girl having the cervical deformity developed on the background of influenza and sore throat and was caused by an apparently minor sports injury, with vertebrocervical lesion and rupture of the inner wall of the jugular vein. The painful onset symptomatology, initially attributed to exacerbation of the anginous process and cervical adenitis, evolved towards phonation, deglutition, nervous and final respiratory disturbances. The progressive evolution and gravity of the clinical picture imposed craniocervical surgery, with exclusion of the lateral intramastoid sinus and resection of the extensive ectatic cervicoprevertebral pouch. The authors discuss the mechanism of the vascular lesion, the clinical picture, evolution, diagnosis and therapy, which totaly differed from classical descriptions of phlebectasia of the jugular vein.

Adolescent↗
PubMed1996

Rapid evolution of a coadapted gene complex: evidence from the Segregation Distorter (SD) system of meiotic drive in Drosophila melanogaster.

Segregation Distorter (SD) is a system of meiotic drive found in natural populations of Drosophila melanogaster. Males heterozygous for an SD second chromosome and a normal homologue (SD+) produce predominantly SD-bearing sperm. The coadapted gene complex responsible for this transmission advantage spans the second chromosome centromere, consisting of three major and several minor interacting loci. To investigate the evolutionary history of this system, we surveyed levels of polymorphism and divergence at six genes that together encompass this pericentromeric region and span seven map units. Interestingly, there was no discernible divergence between SD and SD+ chromosomes for any of these molecular markers. Furthermore, SD chromosomes harbored much less polymorphism than did SD+ chromosomes. The results suggest that the SD-system evolved recently, swept to appreciable frequencies worldwide, and carried with it the entire second chromosome centromeric region (roughly 10% of the genome). Despite its well-documented genetic complexity, this coadapted system appears to have evolved on a time scale that is much shorter than can be gauged using nucleotide substitution data. Finally, the large genomic region hitchhiking with SD indicates that a multilocus, epistatically selected system could affect the levels of DNA polymorphism observed in regions of reduced recombination.

Adaptation, Physiological↗
PubMed1995

Clonal evolution of an immunoblastic type non-Hodgkin's lymphoma with der(6)t(1;6)(q11;p11) as its primary cytogenetic abnormality.

Recurrent pleural effusions from a 45-year-old man who was diagnosed as having non-Hodgkin's lymphoma of immunoblastic type were studied cytogenetically. The majority of the metaphases were tetraploid, but there were also lymphoma cells observed with pseudodiploid chromosome constitutions. Cytogenetic analysis by G-banding revealed the existence of at least two cell populations. The karyotype of the minor pseudodiploid clone, which exhibited partial trisomy of 1q11qter and monosomy of 6p11pter as sole abnormalities, was 46,XY,der(6)t(1;6)(q11;p11). The karyotype of the major clone was 92,XXYY,-1,der(6)t(1;6)(q11;p11)x2, +9. The ancestral diploid clone, carrier of the balanced translocation involving chromosomes 1 and 6, was not observed even in the first pleural effusion harvest. The high proportion of tetraploid cells in the recurrent effusions was an indication that these cells were favorably selected in the environment of the somatic cavity. Our cytogenetic findings suggest that partial trisomy of 1q may be a crucial secondary chromosomal abnormality in highly malignant non-Hodgkin's lymphoma. This genetic imbalance was predetermined from the primary abnormality and may be responsible for further tumor progression, as suggested from the clonal evolution in this particular case and, therefore, may be associated with the aggressive biologic behavior of malignant cells.

Chromosome Aberrations↗
PubMed1988

The genomic DNA organisation and evolution of a retrovirus-transmissible family of mouse (VL30) genetic elements.

The sequence organisation of endogenous VL30 elements in the mouse genome was investigated by using a cloned representative of a retrovirus-transmissible VL30 cDNA. The majority of dispersed VL30 sequences could be assigned to a proviral-like structure 5.2-5.3 kbp long and bounded by long terminal repeats (LTRs). The existence of a hierarchy of evolutionarily conserved elements was rather limited and sequence heterogeneity between different elements was randomly distributed. However, the retrovirus-transmissible class of VL30 element was found to represent a distinct minority subgroup distinguishable by restriction sites and size (4.6-4.9 kbp long). Analysis of sequence conservation showed that VL30 elements display a more rapid turnover than endogenous murine leukaemia virus-related proviral sequences, and that VL30 LTRs show the most limited evolutionary distribution. Although discrete subsets of VL30 unique sequence were conserved in different rodents, the location of conserved regions was found to be variable, arguing against the presence of a functionally conserved protein coding region. These observations support the hypothesis that high frequency recombination, probably occurring during reverse transcription and the accompanying processes of duplicative transposition and amplification, have been a major determinant in the mode of evolution of the VL30 gene family.

Animals↗
PubMed1997

Molecular evolution of hemoglobins of Antarctic fishes (Notothenioidei).

Amino acid sequences of alpha- and beta-chains of human hemoglobin and of hemoglobins of coelacanth and 24 teleost fish species, including 11 antarctic and two temperate Notothenioidei, were analyzed using maximum parsimony. Trees were derived for the alpha- and beta-chains separately and for tandemly arranged sequences, using the human and coelacanth sequences as outgroups in all analyses. The topologies of the trees of the alpha- and beta-chains are highly congruent and indicate a specific pattern of gene duplications and gene expression of teleost hemoglobins which has not yet been investigated into more detail. The Notothenioid fish generally contain a single major hemoglobin and often a second minor component. The alpha- and beta-chains of the major components form a monophyletic group in all investigated trees, with the nonantarctic Pseudaphritis as their sister taxon. The minor chains also are a monophyletic group and form an unresolved cluster with the major chains and the hemoglobins of tuna and red gurnard. The Notothenioid families Nototheniidae and Bathydraconidae appear to be paraphyletic.

Adaptation, Physiological↗
PubMed2002

Evolution of human immunodeficiency virus type 1 populations after resumption of therapy following treatment interruption and shift in resistance genotype.

Conventional genotyping of human immunodeficiency virus type 1 often reveals a shift from a drug-resistant genotype to a wild-type genotype after treatment interruption. A real-time polymerase chain reaction-based technique was used to detect minority resistant populations in 13 patients who showed genotype reversion after interruption of treatment for 3 months. Sixty-two percent of patients in whom the V82A and L90M protease mutations were no longer detectable by conventional genotyping still harbored minority resistant variants, in proportions ranging from 0.1% to 21%. None of the patients with these minority resistant variants who received a protease-inhibitor regimen on resumption of therapy had a response to treatment. However, population sequencing and clonal analysis of plasma samples obtained 1-2 months after resumption of treatment revealed the presence of wild-type virus during the initial decline in plasma virus load, which indicates that minority resistant variants were not rapidly selected.

Amino Acid Sequence↗
PubMed1987

Spontaneous in vitro evolution of lytic specificity of cytotoxic T lymphocyte clones isolated from murine intestinal epithelium.

Three long-term clonally derived cytotoxic lines have been established from isolates of murine intraepithelial lymphocytes (IEL). All three lines were selected for with antigen and represent two allospecific cytotoxic T lymphocyte (CTL) clones and a major histocompatibility complex (MHC)-restricted clone specific for a murine minor histocompatibility antigen. On long-term in vitro culture, IEL clones gradually lost antigen-specific lytic activity and simultaneously acquired the capacity to lyse natural killer (NK)-sensitive target cells which, in some cases, required high-level lymphokine activation. Of interest was the finding that, despite changes in lytic specificity, IEL clones remained strictly antigen-dependent for proliferation. A murine CTL clone of splenic origin, which was propagated under culture conditions identical to those used for IEL, did not exhibit changes in lytic specificity, suggesting that acquired changes in IEL function cannot be attributed solely to the influence of in vitro culture. Phenotypic analyses of IEL clones with altered lytic specificity revealed that all lines remained Thy-1+, Lyt-2+, L3T4-, with or without lytic activation by lymphokines. The expression of CT-1, a murine CTL activation antigen, and asialo GM1, a murine NK cell marker, were variable on IEL clones, and their presence did not correlate with the changes in lytic behavior. Collectively, these findings provide evidence, at the clonal level, that at least some NK activity present in isolates of murine IEL may originate from antigen-specific CTL. The data also indicate that, on binding antigen, different signals are conveyed to T cells, resulting in proliferation or target cell lysis.

Animals↗
PubMed1993

The combined management of cerebral arteriovenous malformations. Experience with 100 cases and review of the literature.

A series of 100 patients treated for a cerebral arteriovenous malformation (AVM) is presented. Patients were admitted between 1985 and April 1992. Two groups are considered: the first group including 52 patients treated before the availability of radiosurgery (1985-1988), and the second group including 48 patients treated after the availability of radiosurgery (1989-1992). AVM's were classified in five grades according to the Spetzler's Grading System. Three techniques of treatment were used: surgical resection, intravascular embolization (with cyanoacrylate), and radiosurgery (linear accelerator). These three techniques were used either alone or in association, giving four types of management: surgical resection alone, embolization and resection, embolization alone, and radiosurgery (alone, or after embolization, or after surgical resection). From 1989 on, the availability of radiosurgery was responsible for the decrease of the "embolization and resection" group, which until then was predominantly used as well for low-grade (I, II, III) as for high-grade AVM's (IV, V). Overall, for the low-grade AVM's, the treatment of choice was surgical resection (79% of cases), with pre-operative embolization in one-half of these cases; the other low-grade AVM's were irradiated, with various combinations. For the high-grade AVM's, the treatment of choice was intravascular embolization (95% of cases), either alone, or followed by resection (45%) or radiosurgery (9%). Results were evaluated in terms of deterioration following treatment, in five groups: no deterioration (59%), minor deterioration (20%), long-lasting deficit (10%), major deterioration (5%), and death (6%). Overall, results improved after 1989: favourable outcome (no deterioration and minor deterioration) increased from 67% to 90%. Results were not related to the patients' age. More favourable results were obtained for low-grade AVM's (93%) than for high-grade AVM's (60%). For the low-grade AVM's the evolution from 1989 on (favourable outcomes increasing from 89% to 96%) occurred with the lowering of the mortality rate. For the high-grade AVM's, the evolution from 1989 onwards (favourable outcome increasing from 46% to 78%) occurred with the decrease of the cases with deficits. The angiographic results were strongly related to the management: 95% of complete eradication after surgical resection and 5% only after embolization alone. Concerning the results in irradiated cases, the follow-up is not long enough. The review of the neurosurgical literature since 1972 demonstrates progressive modifications in the therapeutic attitude as regards AVM's. The surgical management which was predominantly used at the beginning gave way progressively to a combined management, with a combination of embolization, surgery, and lately radiosurgery.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗