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K S Berman

Publications and source records attributed to K S Berman.

8 recordsLinked to original sources
PubMed2001

kin-18, a C. elegans protein kinase involved in feeding.

TAO1 and TAO2 are recently described protein kinases whose initial characterization has placed them at the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) kinase kinase (MEKK) level of stress-responsive MAPK pathways. Because their physiological roles have not been identified, we sought to study their C. elegans homolog to learn more about their functions. kin-18 encodes a previously uncharacterized protein in C. elegans whose catalytic domain shares over 60% identity with TAO1 and TAO2. We demonstrate that KIN-18 is a protein of 120 kDa whose promoter is active in the pharynx and intestine of C. elegans. To learn more about TAO/KIN-18 function, we studied how expression of constitutively active forms of TAO1 or KIN-18 would affect the physiology of intact worms. Strains of C. elegans expressing active forms of TAO1 or KIN-18 exhibit altered pharyngeal electrophysiology as measured by electropharyngeogram. These worms grow more slowly and lay fewer eggs, phenotypes that could result from reduced feeding. We have also identified a C. elegans gene that encodes a protein kinase similar to mammalian MAPK/ERK Kinase (MEK) 4 whose promoter is active in the pharynx. It is phosphorylated by TAO1 in vitro and physically interacts with TAO1.

Amino Acid Sequence↗
PubMed1999

Internal fixation of phalangeal fractures using titanium miniplates.

Although widely utilized in the treatment of metacarpal fractures, plate fixation in phalangeal fractures remains controversial. Increased potential for infection, breakage, and added soft-tissue trauma leading to increased joint stiffness have been cited as important negative factors. A retrospective analysis of titanium plate fixation of phalangeal fractures over a 7-year period is presented. From 1991 to 1998, 16 fractures (13 men, 3 women; age range, 19-70 years) were managed with plate fixation using the Profyle titanium plating system as the primary modality of treatment. All plates were seated dorsally using an extensor tendon-splitting approach. The average follow-up period after surgery was 5 months (range, 3-28 months). Fracture patterns varied: 31% (5 of 16) were open fractures and 69% (11 of 16) were closed. Complications occurred in 25% of patients (4 of 16) and consisted of pain or other trigger that required removal of hardware, flexion contracture at the proximal interphalangeal joint, and extensor lag. There were no instances of hardware failure, infection, or malunion. The quality of recovery of joint motion was assessed using the Total Active Flexion Scale: nine digits were graded excellent, another six were categorized as good, and only one digit was judged as poor. A review of the current literature is presented along with suggested guidelines for the application of miniplate fixation for fractures of the phalanges.

Adult↗
PubMed1998

Isolation of TAO1, a protein kinase that activates MEKs in stress-activated protein kinase cascades.

Several components of the budding yeast pheromone-response pathway are conserved in mammalian mitogen-activated protein (MAP) kinase pathways. Thus, we used degenerate oligonucleotides derived from the sequence of the Saccharomyces cerevisiae protein kinase Ste20p to amplify related sequences from the rat. One of these sequences was used to clone a rat Ste20p homolog, which we called TAO1 for its one thousand and one amino acids. Northern analysis shows TAO1 is highly expressed in brain, as is a homolog TAO2. Recombinant TAO1 was expressed and purified from Sf9 cells. In vitro, it activated MAP/extracellular signal-regulated protein kinase (ERK) kinases (MEKs) 3, 4, and 6 of the stress-responsive MAP kinase pathways, but not MEK1 or 2 of the classical MAP kinase pathway. TAO1 activated MEK3 but not MEK4 or MEK6 in transfected cells. MEK3 coimmunoprecipitated with TAO1 when they were expressed in 293 cells. In addition, immunoreactive MEK3 endogenous to Sf9 cells copurified with TAO1 produced from a recombinant baculovirus. The activation of and binding to MEK3 by TAO1 implicates TAO1 in the regulation of the p38-containing stress-responsive MAP kinase pathway.

Amino Acid Sequence↗
PubMed1985

Effects of needle shape on the integrity of the vascular endothelium.

Lesions generated by the passage of micro-needles through vessel walls are of concern because any lesion may significantly alter hemodynamics of an anastomosis. To study this problem, three different needles were tested on the exposed carotid arteries of 30 rats: the 100 mu taper point, the 100 mu cutting point, and the 75 mu taper point. Trauma generated by the penetration of needles was tested first as the needle and its attached suture was passed through the vessel, then the suture was left in place. One hour after penetration, the arteries were prepared for scanning electron microscopy. Differences between the 100 mu taper point and the 75 mu taper point were significant in terms of size and extent of lesions. An arc of endothelial cells surrounding the wounds showed flattening, tissue destruction and clotting. To minimize endothelial trauma, taper point needles are superior to cutting needles. The 100 mu cutting needle caused damage to the vessel wall in tissue cutting on needle penetration, causing a slit-like incision, and in aggregation of platelets at the puncture site.

Animals↗