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Biomedical subjects

I Kaplan

Publications and source records attributed to I Kaplan.

At least 73 records · Page 4Linked to original sources
PubMed1994

The kinetics of infection of zucchini squash by cucumber mosaic virus indicate a function for RNA 1 in virus movement.

The differential rate of systemic symptom induction in zucchini squash by the Fny- and Sny-strains of cucumber mosaic virus (CMV) previously was mapped to RNA 1, which encodes a protein (1a) involved in virus replication. Examination of the kinetics of accumulation of the RNAs and the four encoded proteins in the inoculated cotyledons showed that the Fny-CMV-associated products generally appeared earlier than the Sny-CMV-associated products. In the systematically infected leaves, this difference was magnified, with a 2-day delay in the appearance of the Sny-CMV RNAs and encoded proteins. However, both Fny-CMV and Sny-CMV RNAs showed similar kinetics of RNA, 2a, 3a, and coat protein accumulation in protoplasts prepared from zucchini squash cotyledons. These data indicate that the differential rate of systemic symptom development was due to a difference in the rate of movement rather than the rate of replication. This was confirmed by a leaf-detachment assay, which showed a difference in the rate of systemic movement by Fny-CMV vs Sny-CMV, and by leaf-press blot hybridization of the inoculated cotyledons at different days postinoculation, which showed a difference in the rate of cell-to-cell movement by the two strains of CMV. Taken together, these data show that the rates of cell-to-cell and long-distance movement can be regulated by sequences in CMV RNA 1, previously thought to be involved only in virus replication.

Cucumovirus↗
PubMed1994

Predictors of survival after a positive post-irradiation prostate biopsy.

PURPOSE: Considerable debate persists in the urologic oncology literature with regard to the optimum management of patients with a positive post-irradiation prostate biopsy. This analysis characterizes a group of such patients who have had a favorable course without intervention. METHODS AND MATERIALS: Between 1956 and 1991, 116 patients have had a positive prostate biopsy 12 or more months post-irradiation without hormonal intervention or evidence of distant relapse. The population had an age range of 42 to 82 years (median - 61). American Joint Committee on Cancer stages included 1 T1, 70 T2, 44 T3, and 1 T4. Median actuarial survival for the entire population was 14.4 years (range = 2.2-21.5 years) from presentation and 5.2 years from re-biopsy. RESULTS: Fifty-one of the 116 patients developed metastases subsequent to re-biopsy and 65 remain free from distant relapse. Among these 65 patients, 50 remain alive and otherwise well, 11 have died of other causes, and only four have succumbed to their local disease. The best predictor of distant relapse subsequent to re-biopsy was digital rectal exam. Forty-one of the 51 patients later developing metastases had an abnormal digital rectal exam compared to 37 of 65 with sustained distant control (p = .01). CONCLUSION: These data demonstrate that long-term, disease-free (other than re-biopsy) survival is common following a "positive" post-irradiation biopsy without intervention especially among patients with a normal digital rectal exam. Therefore, routine re-biopsy without clinical indications is not a useful practice.

Adenocarcinoma↗
PubMed1994

Flexible waveguides for IR laser radiation and surgery applications.

Flexible plastic waveguides were developed to deliver IR radiation, especially at 10.6 microns, which is the CO2 laser radiation wavelength. The waveguide is made from teflon tube with the inner wall coated with a metal layer and a dielectric overlayer. The internal diameter (ID) is 1.0 mm, length 1.0-1.2 m, and the distal tip decreases moderately to ID approximately 0.6 mm. The distal part on the last 10 centimeters is coated externally with a metal layer. Maximum power that can be delivered at the outlet is approximately 30 W and 10.6 x 10(3) W/cm2. This type of waveguide was used in several medical operations to evaluate its cutting characteristics and the resistances to heat reflection from the tissue while operating in orifices containing liquid substances.

Carbon Dioxide↗
PubMed1994

Rolling belt injuries in children.

The rolling belts on agricultural machinery attract children who unconsciously grab them. The injuries produced include friction burns, injuries to flexor tendons, digital nerves and arteries, skin in zone 2 and fractures. Subtotal or total amputation may occur. We present the results of such injuries to 44 fingers in 16 children aged 1 to 9. The functional results are not satisfactory. In order to grade the results we have devised a classification to this injury. The survival rate for all fingers was 71%, but in the fingers with circulatory problems the survival rate was 50%. On functional assessment seven patients had a good result, seven moderate, and two fair.

Accidents↗
PubMed1994

Calcifying odontogenic cyst associated with odontoma: a possible separate entity (odontocalcifying odontogenic cyst).

The calcifying odontogenic cyst (COC) has been reported to be associated with odontoma in about 24% of cases. Separation of the cases of COC associated with odontoma (COCaO) may lead to a better understanding of the pathogenesis of this lesion. A screen of the literature revealed 52 cases of COCaO. The male to female ratio was 1:1.9, with a mean age of 16 years. The most common location was the maxilla (61.5%). The radiographic appearance of most cases (80.5%) was of a well-defined, mixed radiolucent-radiopaque lesion. Histologically, the lesions usually consisted of a single large cyst (which is similar to simple COC) with tooth-like structures that appear to be an integral part of the lesion, giving the impression of a single lesion. In addition to the unique histologic features, differences in gender and in distribution were found between the cases of COCaO and those of simple COC. COCaO may be regarded as a separate entity and classified as a benign, mixed odontogenic tumor. The term odontocalcifying odontogenic cyst is suggested.

Adolescent↗
PubMed1994

Peripheral osteoma of the mandible: a study of 10 new cases and analysis of the literature.

Ten new cases of peripheral osteoma of the mandible are described. These lesions are uncommon and only 15 other cases have been reported in the English language literature over the past 30 years. There is evidence to suggest that the peripheral osteoma of the mandible is a traumatically induced reactive lesion and that muscle traction plays a role in its initiation. In view of this possibility, the term "parosteal osseous hyperplasia" may be more appropriate for those lesions in which a positive history of trauma preceded the onset.

Adolescent↗
PubMed1994

The CO 2 laser in mastectomy: a ten-year follow-up.

We compared the healing process, postoperative course, and follow-up of patients who underwent modified radical mastectomy in the conventional way with those who underwent a laser procedure. Sixty women, aged 33 to 77 years, who suffered from carcinoma of the breast were randomly divided into two groups: Group 1: surgery was performed using scalpel and electrosurgery; Group 2: surgery was performed with a CO 2 Sharplan laser, skin-to-skin including the axilla dissection; maximal power, 40-60 W. The postoperative course was uneventful in both groups. Wound healing was normal. Sutures were removed on the tenth day. Patients were followed at the Outpatient Clinic for 10 years. The circumference of the arm and forearm was measured at fixed points before surgery and at follow-up. Mammography and liver and bone scans were performed every year. Four Group 1 patients developed swelling and edema of 2 to 3 cm at 6 to 8 months after surgery. Also two patients from subgroup A developed local recurrence. No edema or swelling or local recurrence could be detected in patients operated by laser. Surgery with laser is preferable to the conventional approach.

Adult↗
PubMed1994

Localization of cystatin mRNA in chicken brain by in situ hybridization.

The cystatins are a superfamily of proteins that inhibit the lysosomal cysteine proteinases, cathepsins B, H, and L. Members of this superfamily have been found in all tissues and biological fluids analyzed. Previous studies have shown that chicken cystatin mRNA is abundant in brain tissue. In this study, a definitive localization of chicken cystatin mRNA in chicken brain was determined by in situ hybridization. Chicken cystatin mRNA was heavily concentrated in the secretory epithelial cells of the choroid plexus. The rest of the brain failed to show a hybridization signal above that of the control sense strand probe, even after long exposures. We conclude that chicken cystatin is synthesized predominantly by the specialized secretory epithelial cells of the choroid plexus and secreted into the cerebrospinal fluid (CSF). We postulate that chicken cystatin functions to regulate proteinase activity in the CSF and therefore may function as a protective factor for the cellular elements of the central nervous system.

Animals↗
PubMed1994

Detection of circulating tumor cells in men with localized prostate cancer.

PURPOSE: Using prostate-specific antigen (PSA) mRNA as a marker for prostatic epithelial cells, we have developed a sensitive technique that involves reverse transcription and polymerase chain reaction (RT-PCR) to detect circulating tumor cells in the peripheral blood of men with prostatic carcinoma (CaP). PATIENTS AND METHODS: A sensitive RT-PCR assay was used to evaluate the peripheral blood of 135 men with a history of CaP. Fourteen men with benign prostate disease, many of whom had elevated serum PSA levels, were used as a control group. RESULTS: All patients with benign prostate disease had a negative result in the RT-PCR assay. Of particular interest was a subgroup of 65 patients with clinically localized CaP evaluated before definitive local therapy. Five of these patients had detectable PSA mRNA by RT-PCR, suggesting circulating tumor cells. Within this group, systemic disease was detected by RT-PCR in some men with PSA levels less than 10 ng/mL and clinical stage B disease. Blood from men with hormone-refractory and progressive CaP demonstrated a higher frequency of PSA mRNA detectable by RT-PCR (10 of 20 patients). In contrast, none of seven patients with newly diagnosed metastatic prostate cancer and only one of seven patients with metastatic, hormone-responsive disease had blood that was positive for PSA mRNA by RT-PCR. CONCLUSION: Circulating tumor cells can be detected in the blood of a subset of patients with clinically localized CaP and a larger subset of patients with progressive metastatic disease.

Base Sequence↗
PubMed1994

Radiological findings in jaws and skull of neurofibromatosis type 1 patients.

Maxillary and mandibular lesions in neurofibromatosis Type 1 (NF1) in patients are described. Radiographic manifestations include radiolucent lesions with well-defined, poorly-defined or irregular diffuse borders. Mandibular lesions were not associated with the inferior alveolar nerve as it coursed within the mandible. In three patients the lesions extended considerably into the cranial bones. The necessity for routine radiographic and CT evaluation of NF1 patients is emphasized.

Adolescent↗
PubMed1994

Microleakage of composite resin restorations with various etching times.

Microleakage was assessed in Class V composite resin restorations, placed in extracted noncarious human premolar teeth after the enamel cavosurface margins of the preparations had been etched with phosphoric acid for 5, 15, or 30 seconds. The restored teeth were thermocycled, placed in methylene blue dye, invested, and sectioned. The extent of dye penetration along the tooth-restoration interface in the three etching groups was compared. The group etched for 5 seconds showed the greatest leakage; leakage was statistically significantly greater than that in the groups etched for 15 or 30 seconds. The tooth-restoration interface at the occlusal and gingival margins showed more leakage than did the mesial or distal margins.

Acid Etching, Dental↗
PubMed1994

A review of noncarious dental cervical lesions.

Noncarious dental cervical lesions are categorized as abrasions, attritions, erosions, or abfractions. From these destructive processes, hypersensitive dentin is a common sequela experienced by the dental patient. Cold air and tactile probing are among the stimuli that precipitate this reaction. A complete patient history and clinical evaluation are essential for an accurate diagnosis. Treatment measures for hypersensitive dentin include restoring the lesion with composite resin or glass-ionomer material, the application of dentin bonding agents and/or fluoride, and iontophoresis therapy.

Dentin Sensitivity↗
PubMed1993

Epidermal nevus syndrome with maxillary involvement.

A female patient with epidermal nevus syndrome is reported. There were linear epidermal nevi, hemihyperplasia of the limbs and tongue, macrocephaly, several ophthalmic malformations, and multiple radiolucent lesions in the limbs and sacroiliac region. At age 14 years, she developed a giant cell granuloma of the maxilla.

Abnormalities, Multiple↗
PubMed1993

A preliminary report on the Stone-Kaplan instrumentation for CO 2 laser periodontics. Phase I: periodontal pocket opening surgical procedure.

A preliminary report on the Stone-Kaplan instrumentation for CO 2 laser periodontics is presented describing the instrumentation and introducing the first phase of its clinical usage. The design enables the introduction of a hollow fiber delivered CO 2 laser beam into the depth of a periodontal pocket enabling invasive surgical procedures to be carried out with exacting control of the laser beam as afforded by the design of the instrumentation. This design enables the performance of pocket-opening surgical procedures with ease of performance for the operator enhanced by the "instrument-in-hand" tactile-feedback and blind-visualization phenomena afforded by this unique design. The basic performance for a periodontal pocket opening procedure is presented here.

Carbon Dioxide↗