Mono-allelic KCNB2 variants lead to a neurodevelopmental syndrome caused by altered channel inactivation

Ion channels mediate voltage fluxes or action potentials that are central to the functioning of excitable cells such as neurons. The KCNB family of voltage-gated potassium channels (Kv) consists of two members (KCNB1 and KCNB2) encoded by KCNB1 and KCNB2, respectively. These channels are major contributors to delayed rectifier potassium currents arising from the neuronal soma which modulate overall excitability of neurons. In this study, we identified several mono-allelic pathogenic missense variants in KCNB2, in individuals with a neurodevelopmental syndrome with epilepsy and autism in some individuals. Recurrent dysmorphisms included a broad forehead, synophrys, and digital anomalies. Additionally, we selected three variants where genetic transmission has not been assessed, from two epilepsy studies, for inclusion in our experiments. We characterized channel properties of these variants by expressing them in oocytes of Xenopus laevis and conducting cut-open oocyte voltage clamp electrophysiology. Our datasets indicate no significant change in absolute conductance and conductance-voltage relationships of most disease variants as compared to wild type (WT), when expressed either alone or co-expressed with WT-KCNB2. However, variants c.1141A>G (p.Thr381Ala) and c.641C>T (p.Thr214Met) show complete abrogation of currents when expressed alone with the former exhibiting a left shift in activation midpoint when expressed alone or with WT-KCNB2. The variants we studied, nevertheless, show collective features of increased inactivation shifted to hyperpolarized potentials. We suggest that the effects of the variants on channel inactivation result in hyper-excitability of neurons, which contributes to disease manifestations.

POU3F3-related disorder: Defining the phenotype and expanding the molecular spectrum

POU3F3 variants cause developmental delay, behavioral problems, hypotonia and dysmorphic features. We investigated the phenotypic and genetic landscape, and genotype-phenotype correlations in individuals with POU3F3-related disorders. We recruited unpublished individuals with POU3F3 variants through international collaborations and obtained updated clinical data on previously published individuals. Trio exome sequencing or single exome sequencing followed by segregation analysis were performed in the novel cohort. Functional effects of missense variants were investigated with 3D protein modeling. We included 28 individuals (5 previously published) from 26 families carrying POU3F3 variants; 23 de novo and one inherited from an affected parent. Median age at study inclusion was 7.4 years. All had developmental delay mainly affecting speech, behavioral difficulties, psychiatric comorbidities and dysmorphisms. Additional features included gastrointestinal comorbidities, hearing loss, ophthalmological anomalies, epilepsy, sleep disturbances and joint hypermobility. Autism, hearing and eye comorbidities, dysmorphisms were more common in individuals with truncating variants, whereas epilepsy was only associated with missense variants. In silico structural modeling predicted that all (likely) pathogenic variants destabilize the DNA-binding region of POU3F3. Our study refined the phenotypic and genetic landscape of POU3F3-related disorders, it reports the functional properties of the identified pathogenic variants, and delineates some genotype-phenotype correlations.

Insurance denials and diagnostic rates in a pediatric genomic research cohort

PURPOSE

This study aimed to assess the amount and types of clinical genetic testing denied by insurance and the rate of diagnostic and candidate genetic findings identified through research in patients who faced insurance denials.

METHODS

Analysis consisted of review of insurance denials in 801 patients enrolled in a pediatric genomic research repository with either no previous genetic testing or previous negative genetic testing result identified through cross-referencing with insurance prior-authorizations in patient medical records. Patients and denials were also categorized by type of insurance coverage. Diagnostic findings and candidate genetic findings in these groups were determined through review of our internal variant database and patient charts.

RESULTS

Of the 801 patients analyzed, 147 had insurance prior-authorization denials on record (18.3%). Exome sequencing and microarray were the most frequently denied genetic tests. Private insurance was significantly more likely to deny testing than public insurance (odds ratio = 2.03 [95% CI = 1.38-2.99] P = .0003). Of the 147 patients with insurance denials, 53.7% had at least 1 diagnostic or candidate finding and 10.9% specifically had a clinically diagnostic finding. Fifty percent of patients with clinically diagnostic results had immediate medical management changes (5.4% of all patients experiencing denials).

CONCLUSION

Many patients face a major barrier to genetic testing in the form of lack of insurance coverage. A number of these patients have clinically diagnostic findings with medical management implications that would not have been identified without access to research testing. These findings support re-evaluation of insurance carriers' coverage policies.

Genomic answers for children: Dynamic analyses of >1000 pediatric rare disease genomes

PURPOSE

This study aimed to provide comprehensive diagnostic and candidate analyses in a pediatric rare disease cohort through the Genomic Answers for Kids program.

METHODS

Extensive analyses of 960 families with suspected genetic disorders included short-read exome sequencing and short-read genome sequencing (srGS); PacBio HiFi long-read genome sequencing (HiFi-GS); variant calling for single nucleotide variants (SNV), structural variant (SV), and repeat variants; and machine-learning variant prioritization. Structured phenotypes, prioritized variants, and pedigrees were stored in PhenoTips database, with data sharing through controlled access the database of Genotypes and Phenotypes.

RESULTS

Diagnostic rates ranged from 11% in patients with prior negative genetic testing to 34.5% in naive patients. Incorporating SVs from genome sequencing added up to 13% of new diagnoses in previously unsolved cases. HiFi-GS yielded increased discovery rate with >4-fold more rare coding SVs compared with srGS. Variants and genes of unknown significance remain the most common finding (58% of nondiagnostic cases).

CONCLUSION

Computational prioritization is efficient for diagnostic SNVs. Thorough identification of non-SNVs remains challenging and is partly mitigated using HiFi-GS sequencing. Importantly, community research is supported by sharing real-time data to accelerate gene validation and by providing HiFi variant (SNV/SV) resources from >1000 human alleles to facilitate implementation of new sequencing platforms for rare disease diagnoses.

22q11.2 duplications: Expanding the clinical presentation

22q11.2 duplication syndrome has a frequency of ~1/700 in the intellectual disability population. Despite this frequency, there is limited information on the variable clinical presentation. Although the phenotype and incidence of congenital anomalies are well described for 22q11.2 deletion syndrome, they are not as well understood for individuals with 22q11.2 duplication syndrome. This study is a single-center, retrospective review of patients diagnosed with 22q11.2 duplication syndrome designed to categorize the variable phenotype seen in these individuals. The data suggest that the incidence of congenital anomalies may be higher than previously reported for this syndrome. Affected individuals are at increased risk for a variety of problems including gastrointestinal complications, endocrine dysfunction, ophthalmologic abnormalities, palatal anomalies, congenital heart disease, musculoskeletal differences, and neurologic abnormalities. Individuals with 22q11.2 duplication syndrome would benefit from care coordinated by a multidisciplinary team and managed according to the 22q11.2 deletion syndrome guidelines.

Warmblood fragile foal syndrome type 1 mutation (PLOD1 c.2032G>A) is not associated with catastrophic breakdown and has a low allele frequency in the Thoroughbred breed

Background

Catastrophic fractures are among the most common cause of fatalities in racehorses. Several factors, including genetics, likely contribute to increased risk for fatal injuries. A variant in the procollagen‐lysine, 2‐oxoglutarate 5‐dioxygenase1 gene (PLOD1 c.2032G>A) was shown to cause Warmblood fragile foal syndrome type 1 (WFFS), a fatal recessive defect of the connective tissue. Screening of multiple horse breeds identified the presence of the WFFS allele in the Thoroughbred. PLOD1 is involved in cross‐linking of collagen fibrils and thus could potentially increase the risk of catastrophic breakdown.

Objectives

Estimate the frequency of the WFFS allele (PLOD1 c.2032G>A) and determine if it is a risk factor for catastrophic breakdown in the Thoroughbred.

Study design

Case–control genetic study.

Methods

Genomic DNA from hair and/or tissue samples was genotyped for the WFFS allele. Fisher’s Exact tests were performed to compare allele and carrier frequencies between the case cohort (catastrophic breakdown, n = 22) and several cohorts with no record of injury (n = 138 raced/trained at same track and season and n = 185 older than 7 years and raced during same season), nonracers (n = 92), and a random sample without consideration for racing history (n = 279).

Results

The frequency of the PLOD1 c.2032G>A variant in the Thoroughbred breed is low (1.2%). Seventeen of 716 Thoroughbreds tested were carriers (2.4%) and no WFFS homozygotes were detected. Only one catastrophic breakdown case carried the WFFS allele. No statistically significant difference in allele or carrier frequency was identified between case and control cohorts (P>0.05 in all comparisons performed).

Main limitations

This study evaluated cases from one single track.

Conclusions

This study demonstrated that the PLOD1 c.2032G>A associated with WFFS is present at very low frequency in Thoroughbreds and is not a genetic risk factor for catastrophic breakdown.

Estimated frequency of the canine hyperuricosuria mutation in different dog breeds

BACKGROUND

Hyperuricosuria is a condition that predisposes dogs to urate urolithiasis. A mutation that causes canine hyperuricosuria was previously identified in 3 unrelated dog breeds. The occurrence of the mutation in additional breeds was not determined.

HYPOTHESIS/OBJECTIVES

Identify additional breeds that have the hyperuricosuria mutation and estimate the mutant allele frequency in those breeds.

ANIMALS

Three thousand five hundred and thirty dogs from 127 different breeds were screened for the hyperuricosuria mutation.

METHODS

DNA samples were genotyped by pyrosequencing and allele-specific polymerase chain reaction methods.

RESULTS

Mutant allele frequencies that range from 0.001 to 0.15 were identified in the American Staffordshire Terrier, Australian Shepherd, German Shepherd Dog, Giant Schnauzer, Parson (Jack) Russell Terrier, Labrador Retriever, Large Munsterlander, Pomeranian, South African Boerboel, and Weimaraner breeds.

CONCLUSIONS AND CLINICAL IMPORTANCE

The hyperuricosuria mutation has been identified in several unrelated dog breeds. The mutant allele frequencies vary among breeds and can be used to determine an appropriate breeding plan for each breed. A DNA test is available and may be used by breeders to decrease the mutant allele frequency in breeds that carry the mutation. In addition, veterinarians may use the test as a diagnostic tool to identify the cause of urate urolithiasis.

Analysis of genetic variation in 28 dog breed populations with 100 microsatellite markers

Dog breeds were created by man choosing for select phenotypic traits such as size, shape, coat color, conformation, and behavior. Rigorous phenotypic selection likely resulted in a loss of genetic information. The present study extends previous dog population observations by assessing the genotypic variation within and across 28 breeds representing the seven recognized breed groups of the American Kennel Club (AKC). One hundred autosomal microsatellite markers distributed across the canine genome were used to examine variation within breeds. Resulting breed-specific allele frequencies were then used in an attempt to elucidate phylogeny and genetic distances between breeds. While the set of autosomal microsatellites was useful in describing genetic variation within breeds, establishing the genetic relatedness between breeds was less conclusive. A more accurate determination of breed phylogeny will likely require the use of single-nucleotide polymorphisms (SNPs).

PCR multiplexed microsatellite panels to expedite canine genetic disease linkage analysis

Modern dog breeds possess large numbers of genetic diseases for which there are currently few candidate genes or diagnostic tests. Linkage of a microsatellite marker to a disease phenotype is often the only available tool to aid in the development of screening tests for disease carriers. Detection of linkage to a specific disease phenotype requires screening of large numbers of markers across known affected and unaffected animals. To establish high throughput genome scanning this study placed 100 canine microsatellite markers, arranged by fragment size and fluorescent dye label, into 12 PCR multiplexed panels. The highest degree of multiplexing was 11 markers per panel while the lowest was five markers per panel; each panel was run in one gel lane on automated DNA sequencers. Selection of the markers was based upon chromosomal or linkage group locations, degree of polymorphism, PCR multiplex compatibility and ease of interpretation. The marker set has an average spacing of 22.25 centiMorgan (cM). Marker polymorphism was evaluated across 28 American Kennel Club (AKC) recognized breeds. The utility of buccal swab vs. blood samples was also validated in this study as all template DNA was derived from swabs obtained and submitted by participating dog breeders and owners. The PCR multiplexed microsatellite panels and sampling method described in this report will provide investigators with a cost effective and expedient means of pursuing linkage studies of specific canine genetic diseases.

Making dollars out of DNA. The first major patent in biotechnology and the commercialization of molecular biology, 1974-1980

In 1973-1974 Stanley N. Cohen of Stanford and Herbert W. Boyer of the University of California, San Francisco, developed a laboratory process for joining and replicating DNA from different species. In 1974 Stanford and UC applied for a patent on the recombinant DNA process; the U.S. Patent Office granted it in 1980. This essay describes how the patenting procedure was shaped by the concurrent recombinant DNA controversy, tension over the commercialization of academic biology, governmental deliberations over the regulation of genetic engineering research, and national expectations for high technology as a boost to the American economy. The essay concludes with a discussion of the patent as a turning point in the commercialization of molecular biology and a harbinger of the social and ethical issues associated with biotechnology today.

Effect of standard total knee arthroplasty surgical dissection on human patellar blood flow in vivo: an investigation using laser Doppler flowmetry

We examined the in vivo alterations of human patellar bone blood flow that occur with surgical dissection of the extensor mechanism during total knee arthroplasty. A laser doppler probe was used to measure central patellar blood flow at baseline after quadriceps tenotomy, after partial fat pad excision, after lateral release, and after completion of the lateral release with superolateral geniculate sacrifice. The initial quadriceps tenotomy and medial arthrotomy decreased patellar vascularity to 60.4% of baseline. Fat pad resection initiated another 10.4% decline. The lateral release resulted in a patellar vascularity that was 43.6% of baseline. Finally, the loss of superolateral geniculate inflow reduced the patellar flow to 30.61% of baseline.

Results of surgery for spinal stenosis adjacent to previous lumbar fusion

The literature provides little data to guide surgical management of spinal stenosis adjacent to previous lumbar fusion. Thirty-three consecutive patients who had surgical decompression for spinal stenosis at the lumbar segments adjacent to a previous lumbar fusion were studied. The mean interval between fusion and the adjacent segment surgery was 94 months. Of the 33 patients, 26 were followed for 3-14 years (mean: 5 years) after adjacent segment surgery and were clinically evaluated and independently completed an outcome questionnaire. Of the 26 patients, 15 rated their outcome as completely satisfactory, 6 were neutral toward the surgery, and 5 considered their surgery a failure. The surgery was generally effective at improving or relieving lower extremity neurogenic claudication. The strongest independent predictive factor of patient dissatisfaction was ongoing postoperative low back pain (r = 0.7, p = 0.001). A higher back pain score at follow-up was associated with continued narcotic use (p = 0.001) and decreased ability to perform activities of daily living (p = 0.05). Six patients required further lumbar surgery during the follow-up period. This study provides the longest published follow-up data of surgical results for symptomatic spinal stenosis adjacent to a previously asymptomatic lumbar fusion.

Translaminar lumbar epidural endoscopy: technique and clinical results

To provide baseline outcome data for a new lumbar microinvasive diskectomy done with standard arthroscopic instrumentation, we retrospectively reviewed the cases of 190 patients. All patients were assessed by a modified MacNab outcome classification with a minimum of a 2-year follow-up. All complications of this procedure were reported as well. No previous outcome data are available for this procedure, since it has been done primarily at one center, by the same surgeon, using his previously reported techniques. Results were good or excellent in 175 patients and fair or poor in 15. Complications were not severe and were easily remedied. This success rate is comparable to rates reported for other minimally invasive operations on the lumbar spine. This new technique of minimally invasive lumbar spine surgery provides minimal morbidity and a long-term outcome comparable to that of other standard procedures. The added benefits of using standard arthroscopic instrumentation are discussed.

Failed anterior cervical discectomy and arthrodesis. Analysis and treatment of thirty-five patients

Thirty-five patients were managed operatively after failure of an anterior cervical discectomy and arthrodesis. Failure was classified as the absence of fusion without deformity but with neck pain or radiculopathy, or both; the absence of fusion after anterior or posterior dislodgment of the graft; or kyphosis due to collapse of the graft or to an unrecognized posterior soft-tissue injury. Twenty-three patients had failure of the arthrodesis without deformity (with neck pain only, neck and arm pain, radiculopathy, or myelopathy). Four patients had dislodgment of the graft; in two of them the graft migrated anteriorly after a multilevel Robinson arthrodesis, and in two it migrated posteriorly after a Cloward arthrodesis. Eight patients had a failure because of a kyphotic deformity. Five of them had had a Cloward arthrodesis; one, a discectomy; and two, a Robinson arthrodesis. Six had received allograft bone. Operative treatment of the pseudarthrosis consisted of repeat resection of the disc space in the area of the failed arthrodesis followed by repeat anterior Robinson arthrodesis with decompression of the nerve root if the patient had radiculopathy. It consisted of anterior corpectomy or vertebral-body resection and strut-grafting with reduction of the deformity if the patient had migration of the graft and kyphosis. The reoperations were performed four months to fourteen years (average, thirty-two months) after the initial operation. The duration of follow-up after the second operation averaged forty-four months (range, twenty-four to 216 months). The result was excellent for twenty-nine patients, good for one, fair for four, and poor for one. We concluded that, in patients who have persistent symptoms after an anterior cervical arthrodesis, an excellent result can be achieved with repeat anterior decompression and autogenous bone-grafting.

Translaminar lumbar epidural endoscopy: anatomy, technique, and indications

This article describes a new technique to achieve access to the epidural space via a direct posterior portal. This minimally invasive technique allows treatment of disc protrusions and extrusions with full visualization and minimal dissection of the paraspinal musculature. Hemostasis, visualization, and triangulation is performed with standard arthroscopic instrumentation. The anatomy of, indications for, and advantages of this techniques are described.

Shared phenotypic expression of osteoblasts and chondrocytes in fracture callus

Endochondral ossification in fracture healing of rats at 4, 8, 11, 14, and 21 days was analyzed using immunological and molecular probes for markers of the chondrocyte and osteoblast phenotype. These markers were osteocalcin, type I and type II collagen, including the probes homologous to the alternatively spliced forms of alpha 1 type II collagen, type IIA and type IIB. Histologic examination was performed on serial sections of the same tissue blocks to correlate cellular morphology with the immunohistochemical and in situ hybridization findings. At the junction of the cartilaginous and osseous tissue, an overlap of phenotype and morphology was noted. At the 8-day time point, the cells with chondrocyte morphology expressed intracellular message for osteocalcin and type I collagen. Immunohistochemical analysis of these cells also demonstrated intracellular osteocalcin. However, high levels of the type IIA collagen mRNA, which has previously been associated with less differentiated mesenchymal precursor cells, were expressed in both chondrocytes and osteoblasts. At the later time point (21 days) there was a substantial decrease in the number of cells displaying shared phenotypic characteristics. In situ hybridization and immunohistochemistry have permitted identification of an overlapping or shared phenotype in osteoblasts and chondroblasts in fracture callus. The findings raise important questions regarding the possible plasticity of mesenchymal cell phenotypes within the dynamic environment of fracture healing. Additional examination of these issues will further define factors involved in origin, differentiation, and maturation of bone and cartilage cells.

Atrophy of the proximal part of the femur after total hip arthroplasty without cement. A quantitative comparison of cobalt-chromium and titanium femoral stems with use of dual x-ray absorptiometry

The purpose of this study was to compare the density of periprosthetic bone about titanium and cobalt-chromium stems that had been inserted without cement. The analysis was done, three to four years after a total hip arthroplasty, in a retrospectively matched cohort of thirty patients. Fifteen patients had a stem that was collarless, proximally coated, and made of titanium; the other fifteen had a stem of similar design that was made of cobalt-chromium. The criteria for selection in the study included an excellent clinical and radiographic result and separately calculated modified Harris and Mayo hip scores of more than 94 points. All stems had radiographic evidence of osseous ingrowth. A comparison of the bone-mineral density about the two different types of stem with dual-energy x-ray absorptiometry revealed a significant difference only along the calcar of the femur. There was no significant difference about the remaining, preponderant portion of the proximal part of the femur. Our data suggest that the difference in the modulus of elasticity between the two types of stem had little effect on the loss of bone-mineral density in most of the proximal part of the femur after arthroplasty without cement.

The fate of anterior vertebral bone grafts in patients irradiated for neoplasm

Perioperative irradiation is often used with anterior decompression and vertebral interbody fusion for the treatment of spinal neoplasms, yet little is known regarding the healing potential of these grafts. This review of 25 patients with neoplasm who had anterior vertebrectomy, bone strut insertion, and perioperative irradiation was performed to look specifically for evidence of radiographic fusion as determined by plain radiographs, tomograms, or computed tomography reconstruction. Four of 25 patients (16%) were judged to have a pseudarthrosis. All four pseudarthrosis patients but only four of 21 fusion patients had 4000 cg or more of irradiation, a statistically significant difference. There was a trend for lumbar lesions to have a higher risk for nonunion. Concomitant posterior stabilization did not necessarily prevent pseudarthrosis. Two iliac strut grafts with a pseudoarthrosis developed late fracture and one went on to collapse into kyphosis. The pseudarthrosis rate of anterior vertebral strut grafts in the face of irradiation for tumor is relatively high, and late graft fracture can occur if pseudarthrosis develops. Probable risk factors include irradiation greater than 4000 cg and lumbar lesions. Posterior stabilization to protect the graft may be warranted in the highest-risk patients.

A collarless cobalt-chrome femoral component in uncemented total hip arthroplasty. Five- to eight-year follow-up

We implanted 57 uncemented cobalt-chrome porous-coated collarless femoral components into 51 patients (mean age 49 years). At review, five to eight years postoperatively, good or excellent results were recorded in 70% by the Mayo Clinic hip evaluation and in 84% by the Harris hip score. Revision for aseptic loosening of the femoral stem was necessary in only one hip. Thigh pain diminished with time and was present in only two hips at the time of review. Endosteal bone formation was seen at the junction of the smooth and the porous segments of the stem in 94% of hips and in 60% it continued after three years. In 90% of hips, proximal femoral atrophy did not progress after three years. Discontinuous radiolucent lines were seen around 30% of stems, most commonly in zones I, IV and VII. They were not progressive in 94% and their presence did not correlate with the clinical outcome.

Nonradioactive in situ hybridization using digoxigenin-labeled oligonucleotides. Applications to musculoskeletal tissues

We have optimized a technique for in situ localization of specific mRNAs using digoxigenin-11-dUTP-labeled oligonucleotide probes. DNA probes were synthesized for type I and type II collagen as well as transforming growth factor-beta 1 and 2 (TGF beta 1 and TGF beta 2). Control experiments, such as competitive inhibition, nonsense sequence hybridization, and RNAse digestion all indicated that the technique was highly sensitive and specific. In sections of growth plate, type II collagen mRNA was predominantly expressed in the lower proliferative and upper hypertrophic zone, whereas chondrocytes in articular cartilage stained equally. These techniques then were applied to sections cut from archival pathology specimens of musculoskeletal tissues. Primitive chondrocytes in a chondrosarcoma expressed type I and type II collagen mRNA, but did not stain with the nonsense probe. Sections from an osteosarcoma, an aneurysmal bone cyst, and a neurofibroma also were investigated. The ability to use chemically synthesized oligonucleotide probes, the high resolution, and the short development times possible with this in situ procedure makes this technique appealing for applied research into the gene expression of normal and pathologic cellular events.

The role of computerized tomography in the diagnosis of an occult femoral neck fracture associated with an ipsilateral femoral shaft fracture: case report

We report a nondisplaced femoral neck and head fracture diagnosed acutely by CT scanning. This case illustrates the potential benefits of an acute femoral neck/head CT scan in obtunded polytrauma patients with high-energy femoral shaft fractures.

Oliguria in patients with normal renal function

Oliguria is common in critically ill patients and may result from prerenal, renal, and postrenal causes. Oliguria also frequently develops in patients with normal concentrations of blood urea nitrogen and creatinine. Most of these patients do not develop renal failure. The authors prospectively studied 100 patients admitted to the ICU to determine the etiology of oliguria in these patients. Eighteen patients (18%) developed oliguria (less than 0.33 ml.kg-1.h-1 X 2 h). Seven and eleven patients were felt on clinical assessment to be hypovolemic or normovolemic, respectively. Compared with the hypovolemic patients, the normovolemic oliguric patients had significantly lower serum osmolalities (278 +/- 3 vs. 290 +/- 5 mOsm/kg H2O) and serum sodium concentrations (138 +/- 3 vs. 132 +/- 1 mEq/l). In addition, normovolemic patients had significantly higher urine sodium concentrations (83 +/- 12 vs. 13 +/- 2 mEq/l), fractional excretion of sodium (1.14 +/- 0.2 vs. 0.15 +/- 0.03), and renal failure indices (1.5 +/- 0.3 vs. 0.21 +/- 0.04). ADH concentrations in six hypovolemic and six normovolemic patients were increased in both groups but not significantly different. The hypovolemic patients increased their urine output from 17 +/- 2 ml/h to greater than 0.5 ml.kg-1.h-1 following a 500-ml bolus of normal saline. The normovolemic oliguric patients remained oliguric following the saline bolus (13 +/- 2 to 19 +/- 3 ml/h). The authors conclude that oliguria is common in critically ill patients and results from renal hypoperfusion and ADH excess.(ABSTRACT TRUNCATED AT 250 WORDS)

Racial identification from the midfacial skeleton with special reference to American Indians and whites

Successful approaches to race determination of unidentified human remains have been developed by anatomists and physical anthropologists, but few quantitative methods are available for distinguishing American Indian crania from those of whites. The leading method in use today is particularly ineffective in its placement of American Indian skulls from the western regions of the United States. Recent development and testing of a new metric method suggests a much more effective technique. The method involves six breadth and projection measurements of the midfacial skeleton, the calculation of three indices, and a simple direct reading of results. The method has the additional advantage of use in the autopsy room with minimal dissection of soft tissue required. Based upon a less extensive test of East Asian and Arctic Mongoloid crania, the method appears to be even more effective in separating them from the sharp featured whites. Larger samples of American blacks and Polynesians are presently under study and these also appear to separate quite readily from whites using the same or similar sectioning values.

Effect of prenatal alcohol exposure on consumption of alcohol and alcohol-induced sleep time in mice

An animal model was used to examine the effect of maternal alcohol administration on behaviors in the offspring which might predispose to alcoholism. Pregnant C3H mice were administered a liquid diet containing 28% ethanol-derived calories (EDC) from Gestation-Day 8 until parturition. Control animals were either pair-fed an isocaloric 0% EDC diet or received standard lab chow and water throughout pregnancy. Offspring were tested for sleep time following a challenge dose of 3.5 or 4.5 g/kg ethanol at 25 or 110 days of age or for consumption of 10% w/v ethanol in a two-bottle choice situation. The results demonstrated that prenatal exposure to alcohol did not affect alcohol-induced sleep time at either testing age or dose and that waking blood alcohol levels were similar across groups. Voluntary alcohol consumption, however, was higher in mice exposed to alcohol in utero during the initial week of testing but intake decreased to near control levels by the third week. Whether other alcohol-related behaviors are altered by prenatal alcohol exposure remains to be examined.

Decreased ethanol consumption as a function of pregnancy and lactation in C57BL mice

The effects of pregnancy and lactation on alcohol consumption were examined in the C57BL mouse. Pregnant mice were given a two-bottle choice between water and 10% w/v alcohol solution from Day 5 of pregnancy, through two weeks of lactation, and an additional four weeks following the removal of nursing pups. Alcohol consumption was expressed in terms of g absolute ethanol per kg body weight and as an alcohol preference ratio (ml alcohol/ml total fluid). Alcohol consumption (g ethanol per kg body weight) fell below control values during pregnancy and lactation but increased to control levels during postlactation. Similarly, alcohol preference ratio was found to decline during pregnancy, and to further decrease during lactation, a trend that was reversed during postlactation. The results support the findings of decreased alcohol consumption during pregnancy in alcoholic as well as nonalcoholic women.