Health care workers' ability and willingness to report to duty during catastrophic disasters.

Catastrophic disasters create surge capacity needs for health care systems. This is especially true in the urban setting because the high population density and reliance on complex urban infrastructures (e.g., mass transit systems and high rise buildings) could adversely affect the ability to meet surge capacity needs. To better understand responsiveness in this setting, we conducted a survey of health care workers (HCWs) (N =6,428) from 47 health care facilities in New York City and the surrounding metropolitan region to determine their ability and willingness to report to work during various catastrophic events. A range of facility types and sizes were represented in the sample. Results indicate that HCWs were most able to report to work for a mass casualty incident (MCI) (83%), environmental disaster (81%), and chemical event (71%) and least able to report during a smallpox epidemic (69%), radiological event (64%), sudden acute respiratory distress syndrome (SARS) outbreak (64%), or severe snow storm (49%). In terms of willingness, HCWs were most willing to report during a snow storm (80%), MCI (86%), and environmental disaster (84%) and least willing during a SARS outbreak (48%), radiological event (57%), smallpox epidemic (61%), and chemical event (68%). Barriers to ability included transportation problems, child care, eldercare, and pet care obligations. Barriers to willingness included fear and concern for family and self and personal health problems. The findings were consistent for all types of facilities. Importantly, many of the barriers identified are amenable to interventions.

Primary reversed gastric tube reconstruction in long gap esophageal atresia.

BACKGROUND/PURPOSE: Esophageal reconstruction in long-gap esophageal atresia (EA) poses a technical challenge with several surgical options. The purpose of this study was to review the authors' experience with the reversed gastric tube (RGT) in esophageal reconstruction. METHODS: This series describes 7 babies with pure EA treated at 2 centers between 1989 and 2001. Data, gathered by retrospective chart review, included clinical details of the esophageal and associated malformations, technique and timing of repair, early and late complications, and long-term follow-up. Institutional review board (IRB) approval of this study has been obtained. RESULTS: Seven babies were included. Associated malformations were present in 4: trisomy 21 in 2 and imperforate anus in 2. After gastrostomy tube placement, patients were treated with gastrostomy tube feedings and continuous upper pouch suction. Median gap length was 5.5 vertebral segments (range, 3 to 9). RGT with a posterior mediastinal esophagogastric anastomosis was performed at median age of 62 days (range, 38 to 131). There were no anastomotic leaks. Three patients had strictures, one required resection. Exclusive oral nourishment was achieved in 5 patients by 6 months of age. At last follow-up (mean, 4.5 years), 6 patients were receiving oral nutrition exclusively, and all were maintaining growth curves. CONCLUSIONS: In long gap EA, early esophageal reconstruction using an RGT can be performed with minimal morbidity and promising short-term results.

Surgical implications of urachal remnants: Presentation and management.

BACKGROUND/PURPOSE: The abdominal manifestations of urachal remnants often prompt referral to the pediatric general surgeon. The purpose of this study was to evaluate the authors' management of this anomaly. METHODS: The authors performed a retrospective review of patients presenting to their institution with urachal remnants between 1984 and 2001. Clinical and radiographic details of presentation, management, and outcomes are described. RESULTS: Twenty-six patients presented at a median age of 4 years (range, 2 days to 12 years), 16 were boys, and 18 required inpatient care. Eleven (42%) presented with infection, 7 (27%) with clear drainage, 3 (12%) with umbilical polyps/granulation, 3 (12%) with pain, one (4%) with recurrent urinary tract infections, and one (4%) with an asymptomatic punctum. One had an associated anomaly (hypospadias). Urinalysis and urine cultures did not correlate with infection. Ultrasound scan was diagnostic in greater than 90% of cases. Overall, 20 patients underwent primary cyst excision, and 6 underwent incision and drainage (I&D) with delayed excision. Five patients underwent primary excision while infected, and 2 had postoperative complications (wound infection and urine leak). All 6 patients who underwent 2-stage procedure initially presented with infection, and none had complications. CONCLUSIONS: Persistent urachal remnants can present at any age with a variety of clinical manifestations. Ultrasound scan is a reliable diagnostic tool. Additional diagnostic studies generally are not warranted. Simple excision of noninfected lesions is appropriate. In cases of acute infection, initial I&D with delayed cyst excision may be preferable to avoid unnecessary complications.

Evolution and development of teeth.

Teeth as a feeding mechanism in an oral cavity (mouth) are functionally and locationally linked with jaws. In fossils, teeth found in the oral cavity are usually linked with jaws, although mineralised structures with the same histology as teeth are known in fossils before jaws appeared. Denticles in the skin occur in both fossil and extant fish. Pharyngeal denticles also occur in both extant and fossil gnathostomes but in only a few fossil agnathans (thelodonts). Complex structures with dentine and enamel have been described in the earliest jawless vertebrates, conodonts. Such fossils have been used to suggest that teeth and jaws have evolved and developed independently. Our understanding of the developmental biology of mammalian tooth development has increased greatly in the last few years to a point where we now understand some of the basic genetic interactions controlling tooth initiation, morphogenesis and patterning. The aim of this review is to see what this developmental information can reveal about evolution of the dentition.

Developmental genetics and early hominid craniodental evolution.

Although features of the dentition figure prominently in discussions of early hominid phylogeny, remarkably little is known of the developmental basis of the variations in occlusal morphology and dental proportions that are observed among taxa. Recent experiments on tooth development in mice have identified some of the genes involved in dental patterning and the control of tooth specification. These findings provide valuable new insight into dental evolution and underscore the strong developmental links that exist among the teeth and the jaws and cranium. The latter has important implications for cladistic studies that traditionally consider features of the skull independently from the dentition.

Adaptationism and the anthropoid postcranium: selection does not govern the length of the radial neck.

The length of the radial neck has been assumed to vary in living and extinct primates in accordance with its role as a moment arm during flexion by the m. biceps brachii. We here use a simple developmental approach to investigate whether or not this trait does, in fact, vary in such a manner. We find, instead, that virtually all variation in radial neck length is explicable as a simple correlate of overall body size, and that there is no evidence to conclude that selection has separately modified radial neck length in response to differing locomotor patterns. Further implications for the interpretation of mammalian skeletal morphology are briefly discussed.

Subnasal morphological variation in fossil hominids: a reassessment based on new observations and recent developmental findings.

Quantitative and qualitative assessments of subnasal morphology in fossil hominids yield distinct patterns which have been used both to sort robust from nonrobust australopithecine taxa and to distinguish individual species. Recently, new developmental models have been applied to hominoid subnasal morphological variation. These studies require that certain features of the fossil hominid subnasal region, in particular the topography of the nasal cavity entrance and details of vomeral morphology, be reevaluated. This study does so for the robust and nonrobust australopithecines, early Homo (H. habilis/H. rudolfensis), and African H. erectus. Results reaffirm an overall similarity of the nonrobust Australopithecus subnasal morphological pattern with that of the chimpanzee. They further indicate that a vomeral insertion above the nasal surface of the premaxilla should be added to the list of traits characteristic of the robust australopithecine subnasal morphological pattern. Finally, reassessment of subnasal morphology in the early Homo and H. erectus samples from Africa suggest that these two taxa share a similar subnasal morphological pattern. This pattern consists of a smooth nasal cavity entrance, a horizontal nasal sill whose anterior edge is demarcated by a strong nasal crest, and a well-developed horizontal spine at the posterior edge of the nasal sill. Although none of the African fossil Homo specimens preserve a vomer, indirect evidence suggests that it would have inserted above the nasal sill.

Absorption of 2-hydroxy-4-(methylthio)butanoic acid by isolated sheep ruminal and omasal epithelia.

Alimet (Novus Inter., Inc., St. Louis, MO) feed supplement (an 88% aqueous solution of 2-hydroxy-4-(methylthio) butanoic acid; HMB) is a source of L-Met commonly used in nonruminants and ruminants. The absorption of HMB across ovine omasal and ruminal epithelia was evaluated in this study. Ruminal and omasal epithelia were collected from eight lambs (BW = 67.6 kg +/- 9.1) and mounted in parabiotic chambers that were repeatedly sampled throughout a 60-min incubation. The appearance of HMB (using DL-[5-14C]-HMB as a radiolabeled marker) in serosal buffers increased quadratically (P < .004) with time in both tissues. More (P < .001) HMB appeared in the serosal buffers with omasal than with ruminal epithelia. Both tissues responded similarly, and, after 60 min of incubation, the accumulation of HMB within the tissues increased linearly (P < .001) as substrate concentration (.375, .75, 1.5, 3.0, 6.0, and 12.0 mM) increased in mucosal buffers. As the concentration of HMB in the mucosal buffers increased, there was a quadratic (P < .001) increase in the appearance of HMB in the serosal buffer of the omasal epithelium, indicating some saturation of the system. The increase in serosal appearance of HMB was linear (P < .001) with ruminal tissue. The results indicate that there are probably multiple mechanisms involved in the absorption of HMB. Because saturation was observed in the omasum, it is likely that mediated transport accounts for at least a portion of the absorption of HMB in the omasum. Other mechanisms (e.g., diffusion and(or) paracellular absorption) are responsible for the balance of the absorption. Omasal epithelium appears to have a greater capacity for HMB absorption than ruminal epithelium. The enzymes involved in the conversion of HMB to 2-keto-4-(methylthio)butanoic acid were found in ruminal and omasal epithelia, liver and kidney. These results indicate that HMB can be absorbed across ruminal and omasal epithelium and that HMB can be used as a source of L-methionine.

The robust australopithecine face: a morphogenetic perspective.

The robust australopithecines were a side branch of human evolution. They share a number of unique craniodental features that suggest their monophyletic origin. However, virtually all of these traits appear to reflect a singular pattern of nasomaxillary modeling derived from their unusual dental proportions. Therefore, recent cladistic analyses have not resolved the phylogenetic history of these early hominids. Efforts to increase cladistic resolution by defining traits at greater levels of anatomical detail have instead introduced substantial phyletic error.

Risk of sural nerve injury with intramedullary screw fixation of fifth metatarsal fractures: a cadaver study.

The risk of injury to the sural nerve and its branches during operative procedures performed on the lateral foot and ankle is well recognized; however, there have been no anatomic studies demonstrating the proximity of the sural nerve branches to the head of an intramedullary screw used for fixation of fractures of the proximal fifth metatarsal. Dissection of 10 cadaver specimens, after insertion of 4.5-mm screws, demonstrated that the screw head was within 2 mm of the dorsolateral branch of the sural nerve in five specimens and within 3 mm of eight specimens. Irritation of or injury to the nerve during screw insertion may explain the persistence of pain after screw removal in some patients. Furthermore, patients could sustain injury to the sural nerve at the time of screw removal. Careful surgical technique, including the use of drill guides and tissue protectors, may help lessen the risk of sural nerve injury and subsequent neuroma formation.

The Depression-Happiness Scale: test-retest data over two weeks.

The present aim was to examine further the psychometric properties of the Depression-Happiness Scale. Test-retest data over 2 wk. are reported for this scale for a sample of 54 female Northern Irish university students. Stability was fairly high as r = .70, and there was no significant change between Time 1 and Time 2 (M = 49.7 and 50.8, respectively). The data suggest that the Depression-Happiness Scale might be considered a trait measure of happiness rather than a state measure.

Glycyl-L-sarcosine absorption across ovine omasal epithelium during coincubation with other peptide substrates and volatile fatty acids.

To define the interactions between the absorption of glycyl-L-sarcosine (Gly-Sar; .1 mM) and glycine, L-methionylglycine, glycyl-L-leucine, L-carnosine, or L-methionylglycyl-L-methionyl-L-methionine (each at 5 mM), ovine omasal epithelium was collected from eight wethers (average BW=69+/-8.2 kg) and mounted in parabiotic chambers. [1,2]-[14C]Glycyl-L-sarcosine was used as a marker to monitor the presence of Gly-Sar. The Gly-Sar concentration in the omasal epithelium after 60 min of incubation was greatest (P < .05; .0055 nmol/mg dry tissue) when only Gly-Sar was present. Glycine inhibited (P < .05) Gly-Sar movement through the tissue by 20%, and peptide substrates inhibited (P < .05) Gly-Sar movement by 60 to 85%. The appearance of Gly-Sar in serosal buffers increased quadratically (P < .001) with time. Numerically, Gly-Sar appearance in serosal buffers was stimulated by the presence of glycine and peptide substrates. In a second experiment, ovine omasal epithelium was collected from four lambs (average BW=47+/-6.0 kg) to determine the interactions of Gly-Sar absorption (.1 mM) alone or when coincubated with either 10 mM butyric acid, or with a mixture of VFA (50 mM acetic acid, 40 mM propionic acid, and 10 mM butyric acid). The movement of Gly-Sar through the omasal epithelium was greatest (P < .05) when only Gly-Sar was present, and the VFA mixture inhibited (P < .05) Gly-Sar movement by 84%. Results from these studies support the idea that peptides can be absorbed across omasal epithelium and that the process involves mediated as well as nonmediated mechanisms, including possibly paracellular transport.

The influence of splinting on healing tissues.

In addition to immobilizing injured soft tissue to allow healing, splints are used to positively influence collagen remodeling through the application of low-load forces to healing or contracted soft tissue, permitting soft tissue growth and concomitant increased function. When correction of limited passive range of motion due to soft tissue contracture is needed, splinting is an absolute requisite. No other currently available modality is able to hold a constant low-load tension for a prolonged time sufficient to cause tissue growth.

Palatal thickening and facial form in Paranthropus: examination of alternative developmental models.

Paranthropus is distinctive among hominoids in its possession of a greatly thickened hard palate. Although traditionally considered a structural adaptation to counter high-magnitude masticatory stress, alternative developmental models are equally viable. Three models of palatal thickening were evaluated in this study. A mechanical model interprets palatal thickening as a compensatory response to increased instability of the midpalatal suture effected by an anterior placement of the masseteric muscle mass. This model predicts that palatal thickness is correlated with the length of the palate posterior to the masseteric tubercle. Two non-mechanical models consider the thickness of the hard palate to be structurally related to and therefore correlated with either 1) the degree to which the premaxilla overlaps the hard palate in the subnasal region or 2) the height of the posterior facial skeleton. The correlation of craniofacial variables was assessed intraspecifically in ontogenetic series of great ape and human crania. Tests of correlation were performed for each comparison using both residuals calculated from reduced major axis regression of the variable of interest against a measure of cranial size and shape ratios. A significant correlation of palatal thickness with posterior facial height in Pan suggests that the unusually thick hard palate of Paranthropus is directly related to the increased posterior facial height characteristic of this taxon. Further evaluation suggests that extreme palatal thickening in these specimens occurred by virtue of their possession of a nasal septum morphology in which the vomer extends onto the superior and nasal surface of the premaxilla. Such a morphology would have constrained the palatal nasal lamina to maintain the approximate level of the premaxillary nasal lamina throughout the growth process thereby promoting palatal thickening.

Subnasoalveolar anatomy and hominoid phylogeny: evidence from comparative ontogeny.

The present analysis evaluated extant hominoid subnasal morphological variation from an ontogenetic perspective, documenting both qualitative and allometric details of subnasal maturation in Hylobates, great apes and modern humans. With respect to intraspecific variation, results of log-linear modeling procedures indicate that qualitative features of the subnasal region shown previously to discriminate extant taxa (Ward and Kimbel, 1983; McCollum et al., 1993) do not vary appreciably with either age or sex. In terms of quantitative variation, aside from observed changes in the position of the anterior attachment of the nasal septal cartilage relative to the lateral margins of the nasal cavity, the morphology of the subnasal region does not vary appreciably with age. Furthermore, it was found that sexual dimorphism in subnasal form is present only in Pongo and Gorilla and is the result of sexual bimaturism rather than sexual variation in canine size. In considering interspecific variation in subnasal form, there is a propensity among hominoid taxa for the nasal cavity floor to be free of substantial topographic relief. The smoothly continuous nasal floor topography identified in the majority of hominoid taxa appears to be produced by extensive resorption of the anterior nasal cavity floor that accompanies an upward rotation of the anterior maxilla during craniofacial ontogeny. Comparisons of ontogenetic allometric trajectories indicate that relatively little of the variation in hominoid subnasal form can early be attributed to variation in body/cranial size. Instead, variation in craniofacial orientation, vascular anatomy and incisor size and inclination were identified as potential mediators of hominoid subnasoalveolar anatomy. Although results of this analysis confirm that many detail of the orangutan subnasal morphology are derived for this taxon, there is only little conclusive evidence to support recent reports that the morphology displayed by Gorilla is primitive for great apes.