Frequency Of Deformities Research Articles

Interaction of Cortisoi and Thyroid Hormone in the Larval Development of Pacific Threadfin

SYNOPSIS. We have conducted three hatchery-scale experiments designed to examine the actions and interactions of cortisoi and thyroid hormones in the development of a larval marine fish. Survival among controls varied significantly between the 3 replicate experiments. The threadfin (Polydactylus sexfilis) consistently responds to 1 hr posthatch immersion in a combination of triiodothyronine and cortisoi (T3 + F) with accelerated gut development and increased survival compared with untreated controls (C). Survival among larvae treated with T, or F separately was significantly improved over controls in one of the three experiments. The frequency of spinal deformities was reduced by cortisoi treatment, alone or in combination with T3. Growth did not vary with treatment, except that variance in larval length was reduced in (T, + F) vs. C in all 3 experiments. A hormoneinduced increase in uniformity could lead to reduced cannibalism, which is a problem in the culture of threadnns. These results suggest interactive hormonal regulation of developmental processes, working within the context of other biological variables.

Chest wall deformities and thoracic scoliosis after costal cartilage graft harvesting.

Donor-site complications, specifically chest wall deformities and thoracic scoliosis, occurring after harvest of costal cartilage grafts are presented and discussed. The cases of 18 patients (12 male and 6 female), who underwent costal cartilage grafts for microtia reconstruction from 1975 to 1993, were reviewed for donor-site complications using radiography and physical examination. Ribs from which costal cartilage had been harvested showed increased inward bowing on radiographs in 16 of 32 donor sites. The frequency of rib deformity in donor sites was 20.0 percent when cartilages were harvested from patients older than 10 years of age, whereas it was 63.6 percent in patients younger than 10 years old. This difference was statistically significant (p = 0.027, Fisher's exact test), although only 32 grafts were performed in 18 cases. The upper ribs demonstrate a higher incidence of deformity than lower ribs. Thoracic scoliosis was found in 4 of 16 cases. The biomechanical impact of these deformities was considered because of respiratory movement of the thorax and injury to the germinal growth center of the ribs. We recommend delaying costal cartilage grafts for as long as possible, leaving the costochondral junction intact to minimize chest wall deformity and thoracic scoliosis.

Hindlimb deformities (ectromelia, ectrodactyly) in free-living anurans from agricultural habitats.

High prevalences of hindlimb deformities were recorded in wild-caught green frogs (Rana clamitans), northern leopard frogs (Rana pipiens), American toads, (Bufo americanus), and bullfrogs (Rana catesbeiana) from agricultural sites exposed to pesticide runoff in the St. Lawrence River Valley of Québec, Canada, between July and September 1992 and 1993. Of 853 metamorphosing anurans examined in 14 farmland habitats, 106 (12%; range 0 to 69%) had severe degrees of ectromelia and ectrodactyly, compared to only two (0.7%; range 0 to 7.7%) of 271 in 12 control sites. However, the variation in the proportion of deformities among sites was too large to conclude that there was a significant difference between control and pesticide-exposed habitats. Clinical signs varied and were characterized by segmental hypoplasia or agenesis of affected limbs. Conspicuous abnormalities interfered with swimming and hopping, and likely constituted a survival handicap. Because of circumstances and the frequency of these malformations in nine distinct habitats, and in three different species from one of our study sites, we propose a teratogenic action of exogenous factors. Despite the fact that many biotic and abiotic agents are potentially harmful to limb development, agricultural contaminants were suspected as primary aggressors. Thus, clinical examination and frequency of deformities in anurans might be an economical screening tool to assess ecosystem health and the presence of environmental contaminants.

The influence of alcohol consumption on the risk of vertebral deformity

The influence of alcohol consumption on the risk of osteoporosis is not well established. The aim of this study was to determine the relationship between frequency of alcohol consumption and the risk of vertebral deformity across different European populations. A population survey method was used. Men and women aged 50 years and over were recruited from population-based sampling frames in 36 centres from 19 European countries. Subjects were invited to attend by letter of invitation for an interviewer-administered questionnaire and lateral spinal radiographs. Vertebral deformity was defined morphometrically using the McCloskey-Kanis method. Data from 14237 individuals were available for this analysis. Alcohol consumption was compared between the 809 men and 884 women with vertebral deformity and the 5905 men and 6639 women without vertebral deformity. The frequency of alcohol intake was greater in men than women. Overall, there was no detectable association between frequency of alcohol intake and vertebral deformity in either men or women. Stratification by age showed that women 65 years and over who took alcohol on more than 5 days per week had a reduced risk of vertebral deformity compared with those taking alcohol less than once per week. This protection was most obvious after adjusting for age, centre, body mass index, smoking, current level of physical activity and previous fractures (odds ratio [OR] = 0.65; 95% confidence intervals [CI] = 0.43, 0.99). There was a smaller and non-significant protective effect amongst men aged 65 years and over and this was most apparent amongst moderately frequent drinkers (1-4 days per week) (OR = 0.81; 95% CI = 0.62, 1.08). There was no association between the occurrence of vertebral deformity and frequency of alcohol consumption in younger men and women. Overall, the effects of the frequency of alcohol consumption on vertebral deformity were modest. In older women, regular consumption on more than 5 days per week is associated with a reduced risk. Further, prospective data are required to confirm these findings. It is also necessary to investigate, in terms of amount of alcohol consumed, at what level the benefits of regular intake are obviated by the increased risks from alcohol excess.

A follow-up study of congenital non-progressive myopathies

To determine the development and prognosis of patients with the moderate congenital form of congenital non-progressive myopathies (CNM), we investigated 55 patients with CNM by questionnaires. This patient group included 18 with nemaline myopathy, 11 with central core disease, 3 with myotubular myopathy, 15 with congenital fiber type disproportion and 3 with minicore disease. As to motor development, almost all patients had learned to walk alone by 3 years of age, averaging 2 2/12 years. Central nervous system involvement including mental retardation was seen in 24% of the patients, predominantly in patients with myotubular myopathy. The level of mental retardation was not related to the severity of muscle weakness. Patients with central core disease had a higher frequency of skeletal deformities. CNM were not necessarily benign in their prognosis as previously thought, but sometimes showed progressive deterioration leading to death. In 16% of patients, progressive deterioration in muscle strength and respiratory function became manifest after once the patient became ambulant. Even in the benign congenital form, seven of 55 patients died from respiratory or cardiac failures by 20 years of age. Therefore evaluation of cardiopulmonary function at regular intervals is important in the continuing care of patients with CNM.

Chironomid larval deformity frequencies, mortality, and diversity in heavy-metal contaminated sediments of a Canadian riverine wetland

Sediment sampling at point source locations in the Niagara River watershed revealed an area in a Class One Provincially Significant Riverine Wetland that was located near the discharge of a stainless steel company. The site had unusually high concentrations of heavy metals and oily wastes in its sediments. The impacts of these oil and heavy metal contaminated sediments on an invertebrate population of midge (chironomid) larvae was assessed using both lab and field techniques. The midge larvae were the dominant invertebrates in this section of the river. Twenty-six percent of the chironomids from sites located 10 to 800 m downstream of the stainless steel company's point source were deformed. A lab study was carried out to determine what percentage of the observed deformities could be attributed to the heavy metal content of the sediments and what percentage was due to the organic fraction. Sediments collected near the point source were tested and found to be acutely toxic. Sediments collected 60 m downstream of the point source were teratogenic. The frequency of mentum deformities for chironomids reared in clean sediments (control aquaria) was only 2.2%. A similar deformity frequency (2.2%) was observed at the clean sediment reference site in the Welland River watershed. Of the 97 chironomids removed from the de-oiled heavy metal contaminated sediments in the test aquarium, 10.3% displayed deformities. This is believed to be one of the few times that chironomid deformities were induced in a controlled lab study in which heavy metal concentrations similar to those found in the field were used.

The effect of 210Pb and stable lead on the induction of menta deformities in chironomus tentans larvae and on their growth and survival

AbstractTo determine whether menta deformities in chironomid larvae collected from Port Hope Harbour, Ontario, were the result of exposure to ionizing radiation or to heavy metals in the sediment, Chironomus tentans larvae were exposed in the laboratory to concentrations of 210Pb and stable lead representative of contaminant levels in the harbour. Exposure to 100, 1,000, and 2,000 Bq 210Pb g−1 dry sediment had no effect on larval survival, growth, or frequency of deformities. Likewise, exposure to 0.5 and 5.0 mg lead g−1 dry sediment had no effect on the larvae, but exposure to 35.0 mg lead g−1 dry sediment (the maximum levels observed in Port Hope Harbour) resulted in 100% mortality of the larvae. These results indicate that the observed mouthpart deformities in chironomid larvae of Port Hope Harbour are not the result of radiation exposure. They also indicate that heavy metals (lead) may be having an impact on the Port Hope Harbour population. Deformities were observed in all treatments and were confined mainly to the median tooth, with cleft or forked median teeth being the most common deformity. Restriction of the deformities to the median tooth is consistent with an inherited genetic effect, and we consider them to be natural abnormalities. These natural abnormalities must be considered when using chironomid mouthpart deformities as an index of environmental degradation.

Deformities in the menta of chironomid larvae from the Experimental Lakes Area, Ontario

Chironomus spp. larvae in Experimental Lakes Area Lake 382, which received experimental additions of cadmium, were exposed to cadmium concentrations up to approximately 200 ng∙L−1 in water and to about 4 μg∙g−1 in dry sediment, resulting in body burdens of about 3.5 μg∙(g dry weight)−1. Mentum deformities in Chironomus spp. larvae in Lake 382 and five reference lakes ranged from 0 to 16%, which was within the range reported for other contaminated lakes (2 to 83%). The frequency of deformities in Lake 382 was not detectably different either in larvae collected between 1989 and 1992, or in those from reference lakes. Incidence of deformities was higher in four of the five reference lakes than in Lake 382. The constancy of the deformities (confined mainly to the median tooth, commonly with cleft or forked median teeth) is consistent with an inherited genetic effect; therefore, we consider the deformities to be natural abnormalities. We conclude that the low cadmium levels added to Lake 382 did not induce mentum deformities and that background levels of deformities are high (up to 16%) in Experimental Lakes Area lakes. The common occurrence of natural abnormalities must be considered when using chironomid mouthpart deformities as an index of environmental degradation.

Central nervous system imaging in Crouzon's syndrome.

Although the need to prevent the secondary effects of craniosynostosis on the central nervous system is fundamental to the practice of craniofacial surgery, the detailed structural anatomy of the central nervous system in the syndromal craniosynostoses has become the subject of recent interest. A clinical and radiographic review of a population of 59 patients with Crouzon's syndrome determined the frequency of central nervous system deformities. Twelve percent of patients had evidence of decreased mental function. Ventriculomegaly on computed tomographic scan was present in 51% and found to be of three grades: mild, moderate, and severe (hydrocephalus). This was nonprogressive in 7 of the 11 patients with follow-up computed tomographic scans. Ten patients underwent surgical release to increase intracranial space; however, 6 of these patients showed no progression in ventricular size. Nonventricular anomalies were found less frequently (14%). Central nervous system findings show fewer nonventricular anomalies than in Apert's syndrome patients, with a corresponding higher mental function. The principal anomaly of ventriculomegaly is not directly related to suture defect and may represent a primary brain abnormality. Recommendations are made for the assessment and management of patients with Crouzon's syndrome with reference to these areas.

Use of benthic invertebrate community structure and the sediment quality triad to evaluate metal-contaminated sediment in the upper clark fork river, montana

The upper Clark Fork River, above Flathead River, is contaminated with large amounts of As, Cd, Cu, Pb, Mn, and Zn ores from past mining activities. The contaminated area extends from the Butte and Anaconda area to at least 230 km downstream to Milltown Reservoir. Both the upper Clark Fork River and Milltown Reservoir have been designated as U.S. Environmental Protection Agency Superfund sites because of metal-contaminated bottom sediments. We evaluated the impacts of past mining activities on the Clark Fork River ecosystem using benthic invertebrate community assessment, residue chemistry, and toxicity testing. Oligochaeta and Chironomidae generally accounted for over 90% of the benthic invertebrate community in the soft sediment depositional areas. Taxa of Oligochaeta and Chironomidae were predominantly pollution tolerant. Higher numbers of Chironomidae genera were present at stations with higher concentrations of metals in sediment identified as toxic by the amphipod Hyalella azteca in 28-d exposures. Frequency of mouthpart deformities in genera of Chironomidae was low and did not correspond to concentrations of metals in sediment. Total abundance of organisms/m2 did not correspond to concentrations of metals in the sediment samples. Chemical analyses, laboratory toxicity tests, and benthic community evaluations all provide evidence of metal-induced degradation to aquatic communities in both the reservoir and the river. Using a weight-of-evidence approach-the Sediment Quality Triad - provided good concurrence among measures of benthic community structure, sediment chemistry, and laboratory toxicity.

Use of chironomid deformities to assess environmental degradation in the Yamaska River, Quebec

The frequency of morphological deformities in chironomid larvae was used to assess environmental degradation at 12 sites in the Yamaska River, Quebec, that were known to be either impacted by agriculture or urban centres, or were relatively clean and used as reference sites. A total of 2273 chironomid larvae were examined for deformities. The overall frequency of deformities at polluted sites was 2.7%, whereas no deformities were observed at the reference sites. The highest incidence of deformities was found downstream of two urban centres, site 9 at Acton Vale (5.1% deformed) and site 12 at Ste Hyacinthe (5.3% deformed). The frequency of deformities at the agricultural sites ranged from 0.8 to 2.5% and was comparable to sites receiving municipal sewage effluent. The occurrence of higher frequencies of deformities downstream of urban centres indicates that the frequency of deformities increases with environmental degradation.

USE OF BENTHIC INVERTEBRATE COMMUNITY STRUCTURE AND THE SEDIMENT QUALITY TRIAD TO EVALUATE METAL-CONTAMINATED SEDIMENT IN THE UPPER CLARK FORK RIVER, MONTANA

The upper Clark Fork River, above Flathead River, is contaminated with large amounts of As, Cd, Cu, Pb, Mn, and Zn ores from past mining activities. The contaminated area extends from the Butte and Anaconda area to at least 230 km downstream to Milltown Reservoir. Both the upper Clark Fork River and Milltown Reservoir have been designated as U.S. Environmental Protection Agency Superfund sites because of metal-contaminated bottom sediments. We evaluated the impacts of past mining activities on the Clark Fork River ecosystem using benthic invertebrate community assessment, residue chemistry, and toxicity testing. Oligochaeta and Chironomidae generally accounted for over 90% of the benthic invertebrate community in the soft sediment depositional areas. Taxa of Oligochaeta and Chironomidae were predominantly pollution tolerant. Higher numbers of Chironomidae genera were present at stations with higher concentrations of metals in sediment identified as toxic by the amphipod Hyalella azteca in 28-d exposures. Frequency of mouthpart deformities in genera of Chironomidae was low and did not correspond to concentrations of metals in sediment. Total abundance of organisms/m2 did not correspond to concentrations of metals in the sediment samples. Chemical analyses, laboratory toxicity tests, and benthic community evaluations all provide evidence of metal-induced degradation to aquatic communities in both the reservoir and the river. Using a weight-of-evidence approach-the Sediment Quality Triad - provided good concurrence among measures of benthic community structure, sediment chemistry, and laboratory toxicity.

Teratogenic Effects of Selenium in Natural Populations of Fresh Water Fish

The prevalence of abnormalities and associated tissue selenium residues were assessed for the fish population of Belews Lake, North Carolina, and two reference lakes in 1975, 1978, 1982, and 1992. Teratagenic defects identified included lordosis, kyphosis, scoliosis, and head, mouth, and fin deformities. Many fish exhibited multiple malformations and some were grossly deformed and distorted in appearance. Other abnormalities observed were edema, exopthalmus, and cataracts. Whole-body tissue residues of selenium in the fishes of Belews Lake were up to 130 times those in the reference lakes and the incidence of abnormalities was same 7 to 70 times greater. Teratogenic defects increased as selenium levels rose between 1975 and 1982 and fell with declining selenium levels between 1982 and 1992 as selenium inputs into Belews Lake were curtailed. The relationship between selenium residues and prevalence of malformations approximated an exponential function ( R 2 = 0.881, P < 0.01; cubic model) for centrarchids over the range of 1-80 μg/g dry wt selenium and 0-70% deformities. This relationship could be useful in evaluating the role of teratogenic effects in warm-water fish populations suspected of having selenium-related reproductive failure. Unique conditions may have existed in Belews Lake which led to the high frequency and persistence of deformities in juvenile and adult fish. In other, less-contaminated locations competition and predation may eliminate malformed individuals in all but the larval life stage. Teratogenesis could be an important, but easily overlooked phenomenon contributing to fishery reproductive failure in selenium-contaminated aquatic habitats.

Using Mentum Deformities of Chironomus Larvae to Evaluate the Effects of Toxicity and Organic Loading in Streams

The percentage of deformities in Chironomus menta was compared with both an independent measure of stream water quality and predictions of instream toxicity. Simple organic loading caused small (nonsignificant) increases in the frequency of deformities, whereas toxic conditions caused large increases in both the number and types of deformities.

Deformities of Aquatic Larval Midges (Chironomidae: Diptera) in the Sediments of the Buffalo River, New York

We conducted an extensive survey of the benthic macroinvertebrate fauna of the heavily polluted Buffalo River (New York) Area of Concern (AOC), with specific emphasis on assessment of morphological deformities of aquatic larval midges (Chironomidae: Diptera). Sediments were sampled on seven occasions during 1990 - 1991, from as many as 20 sites. Abnormal mouthparts (menta) were most frequent among larvae of the genus Chironomus, occurring in 29.0% of all specimens in the Buffalo River (n = 755), and 22.4% in the adjacent Ship Canal (n = 98). Individual sites in the downstream section of the river yielded even higher deformity frequencies; 36.9% (n = 84), 48.1% (n = 27), and 66.7% (n = 9). The frequencies of abnormalities in this genus at all sites within the AOC were well above levels normally observed (0 - 3%) at non-industrial sites. Additionally, abnormal mouthparts (ligulae) were seen in 3.1% of larvae of the genus Procladius (n = 1,677). While individual downstream samples of Procladius were occasionally as much as 15.4% abnormal (n = 26), this genus was much less prone to morphological deformities than Chironomus. Abnormal menta were also noted in the genera Polypedilum, Cryptochironomus, and Dicrotendipes, but were infrequent. Community parameters such as richness and diversity of the chironomid fauna, and the prevalence of oligochaetes, provide further evidence of decreased environmental quality within the downstream reaches of the Buffalo River. The data presented here provide one biologically relevant measure against which to gauge the effectiveness of pollution abatement strategies within the AOC.

Life Cycle Patterns, Density, and Frequency of Deformities in Chironomus Larvae (Diptera: Chironomidae) over a Contaminated Sediment Gradient

Along a gradient of contamination in Lake Vossemeer (where contaminated sediments from the River Rhine are deposited out), Chironomus cf. plumosus larvae occurred at lower population densities and with higher frequencies of deformities as the contamination levels increased. At the least polluted sites, the frequency of larval deformities was elevated only slightly compared with reference levels. At these sites, C. cf. plumosus had a bivoltine life cycle and overwintered in the fourth larval instar stage. At moderately contaminated sites, the percentage of prepupal larvae was significantly lower in spring and the development of pupae delayed by 2 wk. At heavily contaminated sites, larval densities were strongly reduced and no pupae were observed at all. Under such conditions, population density seems to be a suitable additional indicator of toxic stress. The frequency of deformed larvae was higher from November to April than from July to October. Maximum frequencies were observed during emergence of the overwintering generation, suggesting that the period between February and April may be the most suitable period for the assessment of this parameter.

Evidence of Teratogens in Sediments of the Niagara River Watershed as Reflected by Chironomid (Diptera: Chironomidae) Deformities

Chironomids from two locations in an IJC “Area of Concern” in the Niagara River watershed and from one site in Lake Huron were sampled and classified as either normal or abnormal based on their menta (“teeth”) deformities. The two Niagara River sites were the King's Bridge reference site and the Kane Dock coal tar contaminated area. The latter site was immediately downstream of an abrasives company located about 800 m downstream of the King's Bridge reference site. Among the 739 chironomids sampled from the King's Bridge reference site, 3.1% (23) possessed menta with deformities. This deformity frequency was similar to the 2.8% deformity frequency observed in a clean water site in Lake Huron. Chironomids removed from the coal tar contaminated site displayed a deformity frequency of 14%. The dominant invertebrate in the coal tar (PAH) contaminated sediments was the midge ( Chironomus anthracinus), a non-biting fly larva referred to as a blood worm. Thus there was a significantly higher frequency of menta deformities downstream of the abrasives manufacturer's discharge than at the King's Bridge reference site (Student's “t” test, P < 0.05). The chironomids at the contaminated site were themselves contaminated with elevated levels of fifteen different PAHs. The PAH levels in the bodies of the deformed chironomids were higher than the levels in the undeformed chironomids collected at the same site. When over 200 chironomids with an average deformity frequency of 7.7% were taken from the PAH contaminated site and placed in clean (PAH uncontaminated) sediments taken from the King's Bridge Park reference site, the resulting F 1 generation displayed a mentum deformity frequency of 4%. These rearing experiments indicated that few, if any, of the observed C. anthracinus menta deformities were passed on to the next generation.

The Spine in Diastrophic Dysplasia

Diastrophic dysplasia is an autosomal recessive disorder of the skeleton, characterized by disproportionate short stature, generalized joint deformities, club feet, deformed ear pinnae, and, frequently, spinal deformity and cleft palate. Diastrophic dysplasia is more common in Finland than elsewhere. We studied 101 patients with an age range from newborns to 79 years to find out the frequency and type of spinal deformities, the early signs of progressive cases, and to follow the natural history of the disease. In the follow-up study, 17 patients were under 10 years, 21 under 21 years, and 63 over 21 years of age. One-third of the patients had cervical kyphosis; in the most severe case the kyphosis was 180 degrees and led to quadriplegia during anesthesia. In three patients, cervical kyphosis resolved spontaneously before the age of 5 years. The overall frequency of scoliosis was 37%; 49% in women and 22% in men. Only 13 patients had curves greater than 50 degrees; these curves constituted distinct rotation at the apex from the early evolution of the curve. The early signs of severe curves were detectable at the age of 2 to 4 years. Only two patients were operated on because of scoliosis; one with fusion in situ and the other instrumented with the pediatric Cotrel-Dubousset instrumentation. Three patients had a brace, which did not prevent the progression of the curve. Symptoms referring to a narrow spinal canal were registered in four patients, two of which were operated on; a lumbar posterior decompressive procedure was made at adult age.

Indexing Deformities in Ligulae and Antennae of Procladius Larvae (Diptera: Chironomidae): Application to Contaminant-Stressed Environments

The severity of deformities in the ligulae and antennae of Procladius is indexed and both indices are expanded to include population and community indices and a general index of Chironomid Community Response. These biological indices are compared with Indices of Contamination derived from chemical data from the St. Lawrence River, Port Hope Harbour, Southern Indian Lake – Notigi Reservoir, Tobin Lake, and Last Mountain Lake. Biological and chemical indices both identified Lac St. Louis Site 4 on the St. Lawrence River as the most highly contaminated site and the Wupaw Bay site in the Southern Indian Lake – Notigi Reservoir as the least contaminated of the 23 sites studied. The increase in frequency and severity of deformities in spring and summer data from the Rat Lake basin suggests that larvae are sensitive to increased mercury availability resulting from the greater activity of mercury-methylating bacteria in warmer summer waters.

Split-Thickness Skin Grafting of the Myelomeningocele Defect

The appropriate method and timing of the management of the myelomeningocele defect have prompted considerable discussion. Use of split-thickness skin grafts acutely has accomplished wound closure with low morbidity and mortality. This study was designed to address the question of long-term suitability of the technique of split-thickness skin grafting of the myelomeningocele patient. The incidence of late and/or severe skin ulceration and the presence of gibbus deformity were correlated with the method of skin closure. Long-term follow-up revealed a higher incidence of chronic skin ulceration in the split-thickness skin graft group as compared with the primary closure group. All skin breakdowns appeared in the presence of a gibbus deformity, and gibbus deformity was more prevalent in the split-thickness skin graft group. The incidence of skin ulceration and gibbus deformity was site-dependent. A thoracic or thoracolumbar myelomeningocele repair with split-thickness skin graft was significantly more likely to be complicated by skin problems than the defect in the lumbar, lumbosacral, or sacral region. This relationship was secondary to the frequency of gibbus deformity in the more cephalad defects than defects caudad. A treatment plan is outlined that is based on the primary variable of the location of the myelomeningocele and secondarily by defect size.