PubMed Health⌕ Search

Biomedical subjects

M Gonzales

Publications and source records attributed to M Gonzales.

At least 19 recordsLinked to original sources
PubMed1998

Prenatal diagnosis by FISH of a 22q11 deletion in two families.

We report on prenatal diagnosis by FISH of a sporadic 22q11 deletion associated with DiGeorge syndrome (DGS) in two fetuses after an obstetric ultrasonographic examination detected cardiac anomalies, an interrupted aortic arch in case 1 and tetralogy of Fallot in case 2. The parents decided to terminate the pregnancies. At necropsy, fetal examination showed characteristic facial dysmorphism associated with congenital malformations, confirming full DGS in both fetuses. In addition to the 22q11 deletion, trisomy X was found in the second fetus and a reciprocal balanced translocation t(11;22) (q23;q11) was found in the clinically normal father of case 1. These findings highlight the importance of performing traditional cytogenetic analysis and FISH in pregnancies with a high risk of having a deletion.

Abortion, Induced↗
PubMed1997

Effect of azadirachtin A on the fine structure of the midgut of Rhodnius prolixus.

Rhodnius prolixus fed with azadirachtin A showed significant changes in the ultrastructural organization of the epithelial cells of the stomach and the intestine. Changes included (a) clustering of the microvilli, (b) disorganization of the extracellular membrane layers, (c) modifications in the array of spherocytes, and (d) disorganization of the basal portion of the epithelial cells. We suggest that these changes interfere significantly with the intestinal environment, making it unsuitable for survival and multiplication of the protozoan Trypanosoma cruzi.

Animals↗
PubMed1997

Different proximal and distal rearrangements of chromosome 7q associated with holoprosencephaly.

Four new cases of holoprosencephaly are described in fetuses exhibiting abnormal karyotypes with different distal and proximal rearrangements of the long arm of chromosome 7. Three of them showed terminal deletions of chromosome 7q, confirming the importance of the 7q36 region in holoprosencephaly. The karyotype of the fourth fetus showed an apparently balanced de novo translocation, t(7;13) (q21.2;q33), without any visible loss of the distal part of chromosome 7q. The involvement of new genes, different from the human Sonic Hedgehog gene (hShh) responsible for holoprosencephaly, or a positional effect are discussed.

Amniocentesis↗
PubMed1997

Gamma-hydroxybutyrate: an emerging drug of abuse that causes physical dependence.

Gamma-hydroxybutyrate (GHB) is a compound found in mammalian brain which meets many criteria of a neurotransmitter. GHB has been investigated as a tool for inducing absence (petit mal) seizures, for use as an anesthetic, and for treatment of narcolepsy, alcohol dependence and opiate dependence. Since 1990 GHB has been abused in the United States for euphoric, sedative and anabolic effects. Coma and seizures have been reported following abuse of GHB, but dependence liability has received little attention. The neuropharmacology, potential therapeutic uses and acute adverse effects of GHB are reviewed, followed by a case series of eight people using GHB. Adverse effects of GHB may include prolonged abuse, seizure activity and a withdrawal syndrome. This withdrawal syndrome includes insomnia, anxiety and tremor; withdrawal symptoms resolve in 3-12 days. GHB has the potential to cause a significant incidence of abuse and adverse effects. Prolonged use of high doses may lead to a withdrawal syndrome, which resolves without sequelae. Educational efforts should address the narrow therapeutic index, possible physical dependence and dangers of combining GHB with other drugs of abuse.

Adult↗
PubMed1997

Collaborative study of mosaic tetrasomy 12p or Pallister-Killian syndrome (nineteen fetuses or children).

The difficulties in the diagnosis of Pallister-Killian syndrome are illustrated in this study of nineteen fetuses and children. Diagnosis based on clinical appearance alone is often difficult due to the broad spectrum of clinical anomalies not specific to this syndrome. Due to mosaicism, it is altogether necessary to examine several tissues for the presence of tetrasomy 12p, including circulating lymphocytes in which mosaicism can be as low as 1-3%, amniocytes, chorionic cells and skin fibro-blasts in which mosaicism ranges from 6-100%. When highly suspected on ultrasound examination, the diagnosis recommends prenatal cytogenetic studies because survivors are severely mentally retarded. All the cases are sporadic with only a single preliminary report of recurrence. The cytogenetic diagnosis is therefore helpful in order to reassure family members in regard to genetic counseling.

Abnormalities, Multiple↗
PubMed1997

Patterns of physician use of angiotensin converting enzyme inhibitors in the inpatient treatment of congestive heart failure.

Randomized clinical trails have demonstrated that angiotensin-converting enzyme (ACE) inhibitors reduce mortality, improve symptoms, and decrease hospitalization rates in congestive heart failure (CHF) patients with impaired left ventricular systolic function. Guidelines from the Agency for Healthcare Policy and Research (AHCPR) endorse the use of ACE inhibitors in eligible CHF patients and note their underutilization in practice. Randomly selected records of 1,212 Medicare CHF patients in Louisiana, discharged between July 1993 and October 1993, were reviewed. Abstracted data were used to characterize practice patterns and pertinent clinical factors influencing current ACE inhibitor utilization by practicing physicians in eligible Medicare CHF patients admitted to acute care hospitals. A total of 1,133 patients admitted were discharged alive; mean age was 77.6 years (64% female; 68% white). One third of the patients (34%) were already receiving ACE inhibitors on admission; of these, 85% were discharged on ACE inhibitors. The remaining 66% of patients were not on an ACE inhibitor on admission; only 35% of these are documented to have been placed on an ACE inhibitor(s) at discharge. Overall, a significantly large number of CHF patient charts (48%) lacked documentation of LV systolic function assessments. On multivariate logistic regression modeling, the following key clinical variables were positively related to the prescription of ACE inhibitors: low ejection fraction, dyspnea and orthopnea, normal creatinine levels, high diastolic blood pressure, cardiomegaly, and increasing age. Among patients with low ejection fraction, factors contributing to not being discharged on ACE inhibitors included: high creatinine levels, history of myocardial infarction or ischemic heart disease, renal failure, and being African American. This study documents the underutilization of ACE inhibitors in patients with impaired left ventricular systolic function. Results suggest the need for increased physician-based educational efforts concerning the use of ACE inhibitors in CHF patients, and also for increasing left ventricular systolic function assessments and documentation of findings in patient charts.

Aged↗
PubMed1996

Lethal familial fetal akinesia sequence (FAS) with distinct neuropathological pattern: type III lissencephaly syndrome.

We report on a distinct pattern of primary central nervous system (CNS) degeneration affecting neuronal survival in the brain and spinal cord in 5 fetuses with fetal akinesia sequence (FAS). This neuropathological pattern is characteristic of a lethal entity that we propose calling type III lissencephaly syndrome. Parental consanguinity and the recurrence in sibs support a genetic cause. The mechanism of neuronal death is not yet understood; abnormal apoptosis and/or deficiency in neurotropic factors may be considered possible causes.

Abnormalities, Multiple↗
PubMed1996

Refined mapping of a gene for split hand-split foot malformation (SHFM3) on chromosome 10q25.

Split hand-split foot malformation (SHFM) is a genetically heterogeneous limb developmental defect characterised by the absence of digital rays and syndactyly of the remaining digits. Three disease loci have recently been mapped to chromosomes 7q21 (SHFM1), Xq26 (SHFM2), and 10q25 respectively (SHFM3). We report the mapping of SHFM3 to chromosome 10q25 in two large SHFM families of French ancestry (Zmax for the combined families = 6.62 at theta = 0 for marker AFM249wc5 at locus D10S222). Two recombinant events reduced the critical region to a 9 cM interval (D10S1709-D10S1663) encompassing several candidate genes including a paired box gene PAX2 (Zmax = 5.35 at theta = 0). The fibroblast growth factor 8 (FGF 8), the retinol binding protein (RBP4), the zinc finger protein (ZNF32), and the homeobox genes HMX2 and HOX11 are also good candidates by both their position and their function.

Chromosome Mapping↗
PubMed1994

Prenatal diagnosis of tuberous sclerosis. Use of magnetic resonance imaging and its implications for prognosis.

Tuberous sclerosis (TS) is an autosomal dominant disorder with a high rate of de novo mutation. The real difficulty is to ascertain the diagnosis and to give the neurological prognosis in each case. Prenatal diagnosis of TS is generally based on ultrasonographic signs of multiple cardiac tumours, i.e. rhabdomyomas. Recent progress in magnetic resonance imaging (MRI) enables the diagnosis in a large proportion of cases based on typical brain lesions. It may have a role in the prenatal management of TS, although MRI images seem to underestimate the anatomical findings. Two cases in which TS was diagnosed prenatally are presented with reference to the value of MRI in the prenatal management and comparison with anatomical findings.

Female↗
PubMed1993

Diffuse Lewy body disease with immediate post-partum onset.

A previously healthy 27 years-old woman developed psychotic depression and parkinsonism shortly after delivery of her first child. Her neuropsychiatric symptoms progressed to dementia and she died 5 years after onset. Diffuse Lewy body disease was found at autopsy. This case is unusual because of the early age of onset and the abrupt development of symptoms following pregnancy.

Adult↗
PubMed1993

Proteolysis of Saccharomyces cerevisiae RNase H1 in E coli.

Expression of S cerevisiae RNase H1 in E coli leads to the formation of a proteolytic product with a molecular mass of 30 kDa that is derived from the 39-kDa full length protein. The 30-kDa form retains RNase H1 activity, as determined by renaturation gel assay. The amount of proteolysis observed depends on the procedure used in preparing the cell extracts for protein analysis. The cleavage site on the amino acid sequence of the 39-kDa RNase H1 was determined by N-terminal sequence analysis of the 30-kDa proteolytic form. The cut occurs between two arginines located at the amino terminus region of the protein. The pattern of proteolysis was examined for both the wild-type RNase H1 and a mutant RNase H1 that was constructed in this work. In the mutant the second arginine of the cleavage site was changed to a lysine. Comparisons of the expression of the wild-type and altered protein in two different E coli strains demonstrate that the protease responsible for the degradation has a specificity very similar to that of the OmpT protease. However, the proteolysis observed in an OmpT background in extracts, prepared by boiling the cells in SDS containing buffer, indicates that the protease may, unlike OH108.

Amino Acid Sequence↗
PubMed1993

Primary central nervous system tumours in Australia: a profile of clinical practice from the Australian Brain Tumour Register.

An epidemiological survey of all primary central nervous system tumours in Australia was commenced in 1986. Cases was reported by the treating physician to the Australian Brain Tumour Register, located at the Victorian Cancer Registry. Ninety-three per cent of tumours were histologically confirmed and 69% were reviewed by an independent pathology panel. During the initial 3 years of the survey a total of 4577 brain tumours and 266 primary spinal cord tumours were reported to the Register. The age standardized rates for malignant tumours of the central nervous system, sum to 5.0/100,000 males and 3.4/100,000 females. Twenty-eight per cent of gliomas were biopsied only. Radiotherapy was administered to 57% of cerebral gliomas and 2% of these tumours were treated with adjuvant chemotherapy. Forty per cent of meningiomas were considered to have had a complete tumour resection.

Age Factors↗
PubMed1992

Restrictive dermopathy, a lethal form of arthrogryposis multiplex with skin and bone dysplasias: three new cases and review of the literature.

Restrictive dermopathy is a rare, lethal autosomal recessive syndrome. We report on 3 unrelated affected stillborn infants of consanguineous parents. Clinical findings include a tight, thin, translucent, taut skin, which tears spontaneously in flexion creases, arthrogryposis multiplex congenita (including the temporomandibular joint), enlarged fontanelles, typical face and dysplasia of clavicles and long bones. Histologic abnormalities include hyperplastic, abnormally keratinized epidermis, reduced tonofilaments, thin, compact dermis with hypoplasia of the elastic fibres, and abnormal subcutaneous fat. Fifteen previous cases are reviewed.

Abnormalities, Multiple↗
PubMed1992

Congenital hypothalamic hamartoma syndrome: nosological discussion and minimum diagnostic criteria of a possibly familial form.

We report on congenital hypothalamic hamartomas, discovered at autopsy in 3 unrelated fetuses. In the first 2 patients, the tumor was associated with skeletal dysplasia only. In the third patient, it was part of a non-random congenital malformation association, suggestive of Meckel syndrome. In one family, a previous boy died soon after birth with similar craniofacial and skeletal abnormalities. As far as we know, the association between isolated skeletal dysplasia and congenital hypothalamic hamartomas has not yet been documented in the literature. Nevertheless, a spectrum of skeletal abnormalities has been described in association with congenital hypothalamic "hamartoblastoma" and a constellation of variable visceral malformations under the eponym of "Pallister-Hall syndrome" (PHS). A detailed analysis of the PHS reported cases shows that only skeletal dysplasia and oro-facial abnormalities are present constantly. They show similarities with those found in our first 2 cases. These findings prompt us to consider skeletal dysplasia and oro-facial abnormalities as common denominator and minimum criteria required to define a nosologically distinct, possibly familial entity, which we suggest calling "congenital hypothalamic hamartoma syndrome" (CHHS).

Bone Diseases, Developmental↗
PubMed1992

Arterial supply of the acetabulum in the fetus: application to periacetabular surgery in childhood.

The need to perform triple osteotomies of the pelvis passing very close to the articular surface leads to the isolation of bony fragments whose vascularisation may be precarious. To assess the risks of such surgery, we undertook an anatomic study of the vascularisation of the acetabulum in the fetus. 53 specimens were injected to study the vessels to the acetabulum and their distribution within the osteocartilaginous specimen. The acetabular a., a branch of the obturator a., gives a central pedicle distributed to the acetabular fossa, the triradiate cartilage and ending in the three primary bony components. The superior gluteal, inferior gluteal, internal pudendal and obturator aa. form a periacetabular vascular circle. The abundant vascularity of the acetabulum makes massive necrosis improbable in the child. However, there is a zone of precarious anastomosis at the anterior portion of the acetabulum.

Acetabulum↗