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S Hammond

Publications and source records attributed to S Hammond.

50 records · Page 3Linked to original sources

Histochemistry of sulfhydryls in acute myocardial infarction.

To study the changes in sulfhydryl and disulfide distribution in myocardial infarction we applied the fluorescent sulfhydryl reagent, monobromobimane to sections of myocardium from patients dying of infarction of 24 h to 7 days duration. Staining for both sulfhydryls and for disulfide after reduction of slides blocked with N-Ethyl maleimide showed that sulfhydryls were decreased in the infarcted areas. Disulfides were increased in the periphery of infarction but cells undergoing cytolysis showed loss of disulfide staining as well as sulfhydryl staining. The causes and implication of these changes are discussed.

Bridged Bicyclo Compounds↗

The combined use of selective deuteration and double resonance experiments in assigning the 1H resonances of valine and tyrosine residues of dihydrofolate reductase.

Selective deuteration is a general solution to the resolution problem which limits the application of double resonance experiments to the assignment of the 1H NMR spectra of proteins. Spin-decoupling and NOE experiments have been carried out on Lactobacillus casei dihydrofolate reductase and on selectively deuterated derivatives of the enzyme containing either [gamma-2H6]Val or [alpha, delta 2, epsilon 1-2H3]His, [alpha, delta 1, delta 2, epsilon 1, epsilon 2, zeta-2H6]Phe, [alpha, delta 1, epsilon 3, zeta 2, zeta 3, eta 2-2H6]Trp and [alpha, epsilon 1, epsilon 2-2H3]Tyr. When combined with ring-current shift calculations based on the crystal structure of the enzyme, these experiments allow us to assign 1H resonances of Val 61, Val 115, Tyr 46 and Tyr 68.

Deuterium↗

Experimental evaluation of Harrington rod fixation supplemented with sublaminar wires in stabilizing thoracolumbar fracture-dislocations.

Segments of the spinal column of calves were instrumented with Harrington rods with and without sublaminar wires. Grossly unstable lesions were created by resecting a 2-cm segment from the central spinal segment. Testing on an Instron tester documented the improvement in stability provided by the sublaminar wires in this grossly unstable experimental fracture. Improved stability was seen in resisting axial loading, lateral bending, and forward flexion loading. Rotational stability was particularly improved.

Animals↗

Pediatric pedestrian versus motor vehicle patterns of injury: debunking the myth.

INTRODUCTION: Mechanism of injury has been widely used to enhance the ability of EMS providers to recognize predictable injury patterns. One such pattern, referred to as "Waddell's triad," identifies a triad of injuries associated with pedestrian/motor vehicle collision (MVC), including trauma to the head, abdomen, and lower extremities. We questioned this choice as a common injury pattern for this mechanism. METHODS: A retrospective chart review of 4444 pediatric trauma patients admitted to a regional pediatric trauma center between 1992 and 1996. The source of this information was the medical center's trauma registry. RESULTS: Four-hundred-sixty-five patients suffered a pedestrian/MVC and were included in the study; 231 suffered head injury, and 78 experienced a combination of head and leg injury. Only 11 patients (2.4%) suffered the predicted "triad" of head, leg, and abdominal injury as a result of pedestrian/MVCs. Two of these children suffered minor head injury, and only one patient (0.2%) suffered injury as originally described by Waddell. CONCLUSION: Although the concept of Waddell's triad is logical, and a high index of suspicion should be maintained, the incidence of this predictable injury pattern is low. Educational emphasis should be placed on other aspects of mechanism of pedestrian injury.

Abdominal Injuries↗

The DNA sequence and comparative analysis of human chromosome 20.

The finished sequence of human chromosome 20 comprises 59,187,298 base pairs (bp) and represents 99.4% of the euchromatic DNA. A single contig of 26 megabases (Mb) spans the entire short arm, and five contigs separated by gaps totalling 320 kb span the long arm of this metacentric chromosome. An additional 234,339 bp of sequence has been determined within the pericentromeric region of the long arm. We annotated 727 genes and 168 pseudogenes in the sequence. About 64% of these genes have a 5' and a 3' untranslated region and a complete open reading frame. Comparative analysis of the sequence of chromosome 20 to whole-genome shotgun-sequence data of two other vertebrates, the mouse Mus musculus and the puffer fish Tetraodon nigroviridis, provides an independent measure of the efficiency of gene annotation, and indicates that this analysis may account for more than 95% of all coding exons and almost all genes.

Animals↗

Spiritual and religious components of patient care in the neonatal intensive care unit: sacred themes in a secular setting.

OBJECTIVE: We hypothesized that spiritual distress was a common, unrecognized theme for neonatal intensive care unit (NICU) care providers. STUDY DESIGN: An anonymous questionnaire form assigned to a data table in a relational database was designed. RESULTS: Surveys were completed by 66% of NICU staff. All respondents viewed a family's spiritual and religious concerns as having a place in patient care. Eighty-three percent reported praying for babies privately. Asked what theological sense they made of suffering of NICU babies, 2% replied that children do not suffer in the NICU. Regarding psychological suffering of families, the majority felt God could prevent this, with parents differing (p = 0.039) from nonparents. CONCLUSION: There exists a strong undercurrent of spirituality and religiosity in the study NICU. These data document actual religious and spiritual attitudes and practices and support a need for pastoral resources for both families and care providers. NICU care providers approach difficulties of their work potentially within a religious and spiritual rather than a uniquely secular framework.

Adult↗

Statistical analysis of fine needle aspiration cytology of the breast. A review of 678 cases plus 4,265 cases from the literature.

Between 1979 and 1984, 678 breast fine needle aspiration (FNA) cytologic specimens were received in our laboratory; tissue follow-up was available for 159 cases (23%). The diagnoses rendered in cases with subsequent tissue study were benign (41%), insufficient (10.5%), atypical and/or suspicious for carcinoma (10.5%) and malignant (38%). Using the tissue diagnosis as the standard, there were four false-negative cytologic results and one false-positive result. Considering only cases with a definitive diagnosis of benign or malignant, the sensitivity of cytologic interpretation for diagnosing malignancy on adequate material was 94% while the specificity was 98%; the overall efficiency of the test was thus 96%. The predictive values were 98% for a positive test and 94% for a negative test. Of the total number of submitted cases, a correct and definitive diagnosis was rendered 76% of the time. Calculation of similar statistics from six other series in which the FNA cytologic diagnoses were compared with the histologic diagnoses yielded data almost identical to our findings. The high degree of uniformity in the data indicates that these statistical parameters can be used as standards for evaluating the efficiency of breast FNA cytology.

Academic Medical Centers↗