Unusual juvenile ankle fracture: explanation and surgical repair

Juvenile ankle fractures are reasonably common, comprising approximately 11% of all epiphyseal injuries. They are more common in males and occur most frequently in the age distribution of 11 to 15 years. They characteristically fall into one of the Salter-Harris classification patterns; however, atypical cases do occur that present classification problems and treatment consideration questions. An illustrative case is presented with an explanation, to alert the clinician to these situations and provide a basis for care.     

Biological characteristics of newly diagnosed poor prognosis acute myelogenous leukemia

A pilot study was conducted of the biological characteristics of the leukemia cells of newly diagnosed patients with poor prognosis acute myelogenous leukemia (AML). This study included measurements of the pretherapy proliferative rate of the leukemia cells in vivo, assessment of differentiation in vivo during remission induction therapy, and the level of expression of the fms, myc, and IL1β genes in pretherapy leukemia cells. Short cell cycle times were characteristic of the best prognostic category and were associated with a rapid reduction in marrow leukemia cells in cytosine arabinoside (araC)-sensitive patients. Expression of c-fms was associated with rapid reduction in marrow leukemia cells during araC therapy and with a successful treatment outcome. Expression of the IL1β gene was associated with short remissions. These studies suggest that when compared to newly diagnosed standard prognosis AML, the leukemia of poor prognosis patients is more likely to exhibit long cell cycle times, low levels of fms expression, and is less likely to be associated with myeloid differentiation during remission induction therapy. © 1993 Wiley-Liss, Inc.     

Prognostic significance of blood and marrow findings in acute myelogenous leukemia in remission. A Southeastern Cancer Study Group report

Bone marrow and peripheral blood findings at the time of complete remission were analyzed in 333 patients with acute myelogenous leukemia to determine if any variables were predictive for remission duration and survival. Patients were categorized as to percentage of blasts, promyelocytes, erythroid precursors and lymphocytes in the marrow and hemoglobin concentration, leukocyte and platelet counts, and percentage of granulocytes and blasts in the blood. Additionally, the degree of cellularity in the marrow aspirate and biopsy were analyzed. Patients with less than 1% blasts in the marrow had significantly longer remission durations than those with blasts greater than or equal to 1% (P less than 0.01). Those with hypercellular marrows had significantly shorter remission (P less than 0.05) and survival (P less than 0.01). The transient presence of more than 3% blasts in the blood also was suggestive of a shorter remission duration and survival. The presence of less than 1% blasts in the marrow, normal or decreased biopsy cellularity, and no anemia at the time of remission defined a "good" prognostic group. The quality of remission should be assessed in evaluating the results of therapy and assigning further treatment.     

Shaft osteotomies in hallux valgus reduction

Osteoplasty of the first metatarsal is a form of "plastic surgery" of bone. It is technically demanding and requires a thorough knowledge of anatomy and morphology of bone. Direct dissection techniques are recommended rather than layering, which unnecessarily devascularizes the tissues. Understanding the principles of osteosynthesis and absolute stability is important and will allow the surgeon confidence in knowing that these operative procedures can be performed safely with a high degree of predictability in the correction. These procedures open a new area for consideration in the management of the hallux valgus deformity with intermediate IM angle deformities.     

Integrin expression and osteopontin regulation in human fetal osteoblastic cells mediated by substratum surface characteristics

Integrin-mediated adhesion of anchorage-dependent cells to scaffolds is a critical component of tissue engineering. We investigated integrin expression by the human fetal osteoblastic cell line, hFOB 1.19 (hFOB), as a function of substratum surface wettability. The influence of surface wettability on bone cell phenotype was also examined. Plasma-treated quartz (PTQ) and glass (PTG) (hydrophilic, contact angles of 0 degrees), octadecyltrichlorosilane-treated quartz (STQ) and glass (STG) (hydrophobic, contact angles above about 100 degrees), and tissue culture polystyrene were used for cell culture. hFOB cells cultured on hydrophilic substrata displayed well-developed actin stress fibers relative to cells on hydrophobic substrata. Western blot analysis revealed that hFOB cells cultured on hydrophobic substrata (STQ or STG) express lower levels of alphav and beta3 integrin subunits than do cells on hydrophilic substrata (PTQ or PTG). This effect was more pronounced in cells on STQ than on STG. These variations in integrin expression were lessened by extended culture time. Double- labeled integrin/actin immunofluorescence confirmed Western blot results, that is, cells cultured on PTQ displayed distinct, large plaques of alphav and beta3 subunits and integrin alphavbeta3, as well as their colocalization with actin stress fiber ends, whereas cells on STQ did not display integrin plaques after 24 h and displayed only minimal plaque formation after 3 days. Vinculin, a focal adhesion protein that mediates binding between the integrin and actin cytoskeleton, appeared in Western blots to mimic the variations of alphav and beta3 expression with respect to surface wettability. Interestingly, real-time RT-PCR analysis showed that hFOB cultured on hydrophobic substrata, which have downregulated alphav and beta3 integrin subunits, displayed greater steady state mRNA levels of osteopontin, an extracellular matrix (ECM) protein containing the Arg-Gly-Asp (RGD) integrin recognition sequence, than did cells cultured on hydrophilic substrata. Our results imply that substratum surface wettability regulates integrin-mediated bone cell adhesion and further influences the expression of bone cell-ECM complexes.     

Infection with HIV type 1 group M non-B subtypes in individuals living in New York City

OBJECTIVE: To document infection with HIV type 1 (HIV-1) group M non-B subtypes in individuals living in New York City. DESIGN: From October 1999 through April 2003, HIV-1-seropositive individuals were selected from 3 clinics in New York City based on having risk factors for infection with HIV-1 non-B subtypes. METHODS: HIV-1 RNA was extracted from plasma samples, and partial gag, pol, or env genes were amplified by PCR analysis. The infecting HIV-1 group M subtype was determined based on results of either heteroduplex mobility assay or sequencing and phylogenetic analysis. RESULTS: Ninety-seven subjects were enrolled in the study. Of the 97 subjects, 91 (94%) were selected based on having emigrated from a non-European country, while 6 (6%) were native United States citizens. Subtypes were successfully determined in 53 (55%) of the 97 plasma samples tested. The subtypes in 2 plasma samples were unclassifiable. HIV-1 infections were classified as those due to the following group M subtypes: A (n = 4; 7%), B (n = 12; 22%), C (n = 8; 15%), F (n = 2; 4%), CRF01_AE-like (n = 7; 13%), CRF02_AG-like (n = 19; 34%), an intersubtype recombinant form G/A (n = 1; 2%), and unclassifiable viruses (n = 2; 4%). CONCLUSION: This study reveals infection with a broad variety of HIV-1 group M subtypes mostly in the immigrant population of New York City as well as how several non-B subtypes are being introduced into the United States.     

Acridine orange--RNA histofluorescence of sarcomas and small round cell tumors of childhood.

Forty-nine pediatric malignant neoplasms were stained with acridine orange (AO) fluorochrome to qualitatively evaluate cytoplasmic RNA content. The application of AO as a supplementary stain in surgical pathologic diagnosis is based on the premise that specific neoplastic cell types characteristically and consistently contain few or many cytoplasmic ribosomes. Primitive tumors such as Ewing's sarcoma and primitive neuroectodermal tumors showed negative or low-intensity AO-RNA cytoplasmic staining. Differentiated sarcomas such as rhabdomyosarcomas and lymphomas exhibited moderate to strong AO-RNA cytoplasmic fluorescence. Acridine orange--RNA staining provides an easy, convenient, and inexpensive adjunct in the histopathologic differential diagnosis of sarcomas. It is particularly useful for distinguishing Ewing's sarcomas from other small round cell sarcomas of childhood.     

Time course of hypo-osmotic swellings of human spermatozoa: evidence of ordered transition between swelling subtypes

The hypo-osmotic swelling test (HOST or HOS test) usually takes into consideration the total HOS response value with no emphasis either on the value of the response subtypes or the response evaluation time. This study investigated the time course of HOS responses and analysed their physiological relevance. Raw semen spermatozoa and Percoll washed spermatozoa were used in the experiment. The morphological changes in the sperm tail were monitored by incubating the spermatozoa in the hypo- osmotic solution for 16 different time periods. The HOS reactive spermatozoa and the type of HOS reaction (swelling subtypes) of the samples subjected to different duration of treatment were identified under a phase contrast microscope. Also the fate of individual spermatozoa in a hypo-osmotic environment were monitored for 30 min. In spermatozoa exposed to a hypo-osmotic solution, the motility lasted usually less than 2 min and motility characteristics were uniquely different from that of the spermatozoa under iso-osmotic conditions. The HOS response development was permanent but the motility loss due to hypo-osmotic shock was reversible up to 1 min of incubation. There was an indication of ordered transition among the HOS swelling subtypes apparently initiating with subtype b destined to c, d, e, f and g. Further, the subtypes a and g showed gradual decrease and increase, respectively, while subtype b showed abrupt initial increase and then gradual decrease. Transition from b to g could be direct or via one or more than one subtypes. Ultrastructure based analysis indicated that HOS response subtypes are the apparent reflection of the differences in the cytoskeletal assembly of the sperm tail and thus may be identifying different physiological variants in the sperm population. These results indicate that shorter incubation is essential to document the kinetics of various HOS responses but the conventional HOS test misses these important HOS features because of lengthy incubation. Since the time course of ordered transition of HOS responses will vary more than the total HOS response in semen of different aetiologies, the importance of HOS response subtypes and response evaluation time should be taken into consideration when applying HOS test.