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Biomedical subjects

M C Jones

Publications and source records attributed to M C Jones.

At least 127 records · Page 7Linked to original sources
PubMed1987

Effect of presence or absence of the opposite sex on egg production and semen quality of breeder turkeys.

The effect of the presence or absence of the opposite sex on egg production and semen quality of breeder turkeys was evaluated. Ninety-six female and 36 male Medium White turkeys were used in this study. Two males were released, individually, into each of eight pens of females for 15 min each day, 5 days/wk. Two males in each of four pens of females were physically isolated in wire-enclosed cages in full view of the females. Males assigned to the remaining four pens of females were placed in isolated pens so they were physically, visually, and vocally separated from the females. Egg production was significantly higher for females under natural mating conditions than for females visually exposed to males in holding pens or for females completely isolated from males. Females visually exposed to, but not in contact with males, laid more eggs than those completely isolated from males during the 13th through the 18th week of production. Semen volume and semen concentration was significantly lower, and the percentage normal sperm was higher for males mating naturally than for those maintained in the presence of or completely isolated from females. Semen concentration was highest in isolated males.

Animals↗
PubMed1986

Isolated and syndromic cryptophthalmos.

The association between cryptophthalmos and multiple congenital malformations has been well documented over the last century. Numerous authors have described cases as the cryptophthalmos syndrome, but recently reports of cases without cryptophthalmos have led several authors to use the eponymic designation Fraser syndrome. We have seen seven cases of cryptophthalmos syndrome, including three sib pairs. All presented with cryptophthalmos and bilateral renal agenesis in addition to other characteristic associated malformations. A literature review showed 124 cases in which 27 demonstrated isolated cryptophthalmos, while 97 showed a pattern of multiple congenital malformations. We selected four major and eight minor criteria which enabled us to classify 86 of those cases as having cryptophthalmos syndrome with 11 remaining unclassified. Cryptophthalmos demonstrates equal sex distribution, occurrence in sibs, consanguinity in families with more than one affected child, and lack of vertical transmission--strongly suggesting autosomal recessive inheritance. Isolated cryptophthalmos or cryptophthalmos sequence was sporadic in 16 cases and familial in 11. The familial cases occurred in three families and demonstrated vertical transmission. The pathogenesis of this syndrome is unknown. There are similarities to animal models of maternal vitamin A deprivation and defects in programmed cell death. Cryptophthalmos syndrome should be considered in the differential diagnosis of cases with multiple congenital malformations, especially when they are associated with renal agenesis, even in the absence of cryptophthalmos.

Abnormalities, Multiple↗
PubMed1986

Multiple intestinal atresia and amyoplasia congenita in four unrelated infants: a new association.

Four unrelated infants with multiple segments of nonduodenal intestinal atresia and amyoplasia congenita are described. The extreme rarity of each of these conditions as a single entity indicates that their concurrent incidence in four separate unrelated patients is of significance with respect to pathogenesis. The nature of the relationship between the two conditions is unknown.

Arthrogryposis↗
PubMed1986

Unilateral epicanthal fold: diagnostic significance.

The dysmorphologic evaluations of 56 children with torticollis and plagiocephaly were reviewed. Half of the children were referred because of the cranial asymmetry, and the remainder because of other structural defects or developmental delay. A unilateral epicanthal fold was present in 22 of 54 fully documented cases (41%). In 78% of these, the fold was ipsilateral to the area of occipital flatness. Because most infants are examined in an en face position, the presence of a unilateral epicanthal fold should prompt further investigation for a readily treatable torticollis.

Child, Preschool↗
PubMed1986

Vascular steal: the pathogenetic mechanism producing sirenomelia and associated defects of the viscera and soft tissues.

Dissection of the abdominal vasculature in 11 cases of sirenomelia has demonstrated a pattern of vascular abnormalities that explains the defects usually found in this condition. The common feature is the presence of a single large artery, arising from high in the abdominal cavity, which assumes the function of the umbilical arteries and diverts nutrients from the caudal end of the embryo distal to the level of its origin. The steal vessel derives from the vitelline artery complex, an early embryonic vascular network that supplies the yolk sac. Arteries below the level of this steal vessel are underdeveloped and tissues dependent upon them for nutrient supply fail to develop, are malformed, or arrest in some incomplete stage. In contrast to the prevailing view that sirenomelia arises by posterior fusion of the two developing lower limbs, these studies suggest that the single lower extremity in sirenomelia arises from failure of the lower limb bud field to be cleaved into two lateral masses by an intervening allantois.

Abnormalities, Multiple↗
PubMed1985

An autosomal dominant syndrome of characteristic facial appearance, preauricular pits, fifth finger clinodactyly, and tetralogy of Fallot.

This report describes six relatives with a syndrome of mild prenatal-onset growth deficiency, an altered craniofacial appearance, preauricular pits, and clinodactyly of the fifth finger; three had tetralogy of Fallot. The clinical impact of this condition appears to be related to the severity of the cardiac defect. Autosomal dominant inheritance is implied by the occurrence of the disorder in three successive generations with documented male-to-male transmission. Recognition of this syndrome is important in counseling families regarding recurrence risk for tetralogy of Fallot.

Abnormalities, Multiple↗
PubMed1985

Synthesis and neuroleptic activity of 3-(1-substituted-4-piperidinyl)-1,2-benzisoxazoles.

The synthesis of a series of 3-(1-substituted-4-piperidinyl)-1,2-benzisoxazoles is described. The neuroleptic activity of the series was evaluated by utilizing the climbing mice assay and inhibition of [3H]spiroperidol binding. Structure-activity relationships were studied by variation of the substituent on the benzisoxazole ring with concomitant variation of four different 1-piperidinyl substituents. Maximum neuroleptic activity was realized when there was a 6-fluoro substituent on the benzisoxazole ring. The 1-piperidinyl substituent appeared less significant, although in most cases, the (1,3-dihydro-2-oxo-2H-benzimidazol-1-yl)propyl group imparted maximum potency. The most potent compound in both assays was 6-fluoro-3-[1-[3-(1,3-dihydro-2-oxo-2H-benzimidazol-1-yl) propyl]-4-piperidinyl]-1,2-benzisoxazole (11b).

Animals↗
PubMed1984

Germinoma of the pineal body with syncytiotrophoblastic giant cells.

Almost all types of germ cell tumors are known to occur in the third ventricle-pineal region. In this paper we report the case of a 16-year-old boy having a particular subtype of germinoma of the pineal body in which scattered syncytiotrophoblastic cells positive for human chorionic gonadotropin were found. This tumor is considered the central nervous system counterpart of seminoma with syncytiotrophoblastic giant cells and dysgerminoma with syncytiotrophoblastic giant cells.

Adolescent↗
PubMed1983

Duplication (17p) in a child with an isodicentric (17p) chromosome.

We present a child with multiple structural defects due to duplication of the short arm and a small portion of the long arm of chromosome 17. Three children with similar cytogenetic abnormalities have been reported previously. The karyotype contained an isodicentric chromosome derived from chromosome 17. A clue to the mechanism that produced the isochromosome was retained in the genome in the form of a part of the chromosome 17 long arm which was attached to the short arm of a chromosome 10.

Abnormalities, Multiple↗
PubMed1982

Possible mesodermal origin for axial dysraphic disorders.

We report four patients who provide clinical evidence supporting the hypothesis that axial dysraphic states may result from a primary disturbance in the chordoaxial mesoderm. One infant had complete craniorachischisis, an omphalocele, and ambiguous genitalia. A second infant had anencephaly and an omphalocele. The third had iniencephaly. The fourth had cervical vertebral fusion defects, an occipital menigocele, and a laterality malformation sequence. Alteration in the development of structures derived from the chordoaxial mesoderm could explain all of the structure defects observed in the four patients. This hypothesis accounts for the nature of the defects seen in association with dysraphic disorders and for the genetic relationship observed between neural tube defects and vertebral anomalies.

Abnormalities, Multiple↗