PubMed Health⌕ Search

Biomedical subjects

K Slater

Publications and source records attributed to K Slater.

17 recordsLinked to original sources
PubMed2002

Iatrogenic bile duct injury: the scourge of laparoscopic cholecystectomy.

BACKGROUND: Laparoscopic cholecystectomy (LC) has become the first-line surgical treatment of calculous gall-bladder disease and the benefits over open cholecystectomy are well known. In the early years of LC, the higher rate of bile duct injuries compared with open cholecystectomy was believed to be due to the 'learning curve' and would dissipate with increased experience. The purpose of the present paper was to review a tertiary referral unit's experience of bile duct injuries induced by LC. METHODS: A retrospective analysis was performed on all patients referred for management of an iatrogenic bile duct injury from 1981 to 2000. For injuries sustained at LC, details of time between LC and recognition of the injury, time from injury to definitive repair, type of injury, use of intraoperative cholangiography (IOC), definitive repair and postoperative outcome were recorded. The type of injury sustained at open cholecystectomy was similarly classified to allow the severity of injury to be compared. RESULTS: There were 131 patients referred for management of an iatrogenic bile duct injury that occurred at open cholecystectomy (n = 62), liver resection (n = 5) and at LC (n = 64). Only 39% of bile duct injuries were recognized at the time of LC. Following conversion to open operation, half the subsequent procedures were considered inappropriate. When the injury was not recognized during LC, 70% of patients developed bile leak/peritonitis, almost half of whom were referred, whereas the rest underwent a variety of operative procedures by the referring surgeon. The remainder developed jaundice or abnormal liver function tests and cholangitis. An IOC was performed in 43% of cases, but failed to identify an injury in two-thirds of patients. The bile duct injuries that occurred at LC were of greater severity than with open cholecystectomy. Following definitive repair, there was one death (1.6%). Ninety-two per cent of patients had an uncomplicated recovery and there was one late stricture requiring surgical revision. CONCLUSIONS: The early prediction that the rate of injury during LC would decline substantially with increased experience has not been fulfilled. Bile duct injury that occurs at LC is of greater severity than with open cholecystectomy. Bile duct injury is recognized during LC in less than half the cases. Evidence is accruing that the use of cholangiography reduces the risk and severity of injury and, when correctly interpreted, increases the chance of recognition of bile duct injury during the procedure. Prevention is the key but, should an injury occur, referral to a specialist in biliary reconstructive surgery is indicated.

Adult↗
PubMed2001

Epidemic typhus meningitis in the southwestern United States.

A patient residing in New Mexico had murine typhus diagnosed. A novel molecular assay was performed at the Centers for Disease Control and Prevention, and Rickettsia prowazekii, the agent of epidemic typhus, was found, rather than R. typhi. To our knowledge, this is the first reported case of epidemic typhus confirmed by means of polymerase chain reaction--based testing of cerebrospinal fluid, and it introduces a novel assay for the molecular diagnosis of both epidemic and murine typhus.

DNA, Bacterial↗
PubMed2001

Cytotoxicity tests for high-throughput drug discovery.

Despite theoretical obstacles associated with performing cell-based assays in high-density formats (microplates with at least 384 wells), it is becoming clear that the pharmaceutical industry is now routinely running cell-based tests in these formats. This work is revealing the weakness of established cytotoxicity end points, specifically in relation to sensitivity and reproducibility. New assay kits based on bioluminescent detection of ATP and ADP are now providing the answer to these problems.

Drug Evaluation, Preclinical↗
PubMed2000

Absenteeism and the impact of a 38-hour week, rostered day off option.

We undertook a comparative analysis of nurses working in two consecutive years: one in a 40-hour standard working week and the other in a 38-hour week with a rostered day off per month, in order to determine whether there was any effect on absenteeism. We found that total absenteeism between the two years fell significantly from 4.58% to 4.36% (chi 2 = 5.09, P = 0.024). Sick leave decreased but not to a significant degree. We conclude that the change to the 38-hour week and 19-day month (rostered day off) arrangements led to a significant reduction in overall absenteeism but not in sick leave. However, the cost in implementing a 19-day month is far in excess of any savings made through absenteeism reductions.

Absenteeism↗
PubMed1999

An investigation into the possibility of transmission of tick-borne pathogens via blood transfusion. Transfusion-Associated Tick-Borne Illness Task Force.

BACKGROUND: Tick-borne illnesses were diagnosed in a group of National Guard members, including some who had donated blood a few days before the onset of symptoms. A voluntary recall of those blood components was issued and a multistate investigation was conducted to determine if transfusion-transmitted illness had occurred. STUDY DESIGN AND METHODS: Donors and recipients were asked to complete questionnaires regarding symptoms and risk factors for infection and to provide blood samples for laboratory analysis. RESULTS: Among National Guard personnel who donated blood, 12 individuals were found to have a confirmed or probable case of Rocky Mountain spotted fever or ehrlichiosis. A total of 320 units (platelets or packed red cells) from 377 donors were transfused into 129 recipients. Although 10 recipients received units from National Guard personnel with confirmed or probable infection, none became ill. CONCLUSION: Transfusion-transmitted illness did not occur. Despite the awareness of the risk for tick-borne diseases and the use of tick-preventive measures, many National Guard personnel reported exposure to ticks. In addition to augmenting current tick-preventive measures, scheduling blood drives before rather than after field exercises could further reduce the potential for transmission of tick-borne pathogens.

Adult↗
PubMed1998

Nested PCR assay for detection of granulocytic ehrlichiae.

A sensitive and specific nested PCR assay was developed for the detection of granulocytic ehrlichiae. The assay amplifies the 16S rRNA gene and was used to examine acute-phase EDTA-blood and serum samples obtained from seven humans with clinical presentations compatible with human granulocytic ehrlichiosis. Five of the seven suspected cases were positive by the PCR assay using DNA extracted from whole blood as the template, compared with a serologic assay that identified only one positive sample. The PCR assay using DNA extracted from the corresponding serum samples as the template identified three positive samples. The sensitivity of the assay on human samples was examined, and the limit of detection was shown to be fewer than 2 copies of the 16S rRNA gene. The application of the assay to nonhuman samples demonstrated products amplified from template DNA extracted from Ixodes scapularis ticks collected in Rhode Island and from EDTA-blood specimens obtained from white-tailed deer in Maryland. All PCR products were sequenced and identified as specific to granulocytic ehrlichiae. A putative variant granulocytic ehrlichia 16S rRNA gene sequence was detected among products amplified from both the ticks and the deer blood specimens.

Animals↗
PubMed1998

Operative reconstruction after transverse rupture of the tendons of both peroneus longus and brevis. Surgical reconstruction by transfer of the flexor digitorum longus tendon.

Rupture of the tendons of both peroneus longus and peroneus brevis results in considerable disability. We have performed transfer of flexor digitorum longus (FDL) to peroneus brevis in two patients with lateral instability of the hindfoot due to chronic transverse tears of both tendons for which end-to-end repair was not possible. Both patients had excellent function when reviewed after eight and six years, respectively, with no symptoms. CT showed a normal appearance of the FDL in both patients, but the peroneal muscles looked abnormal. Transfer of the FDL provides a reliable solution to lateral instability of the hindfoot resulting from loss of function of both peronei.

Ankle↗
PubMed1996

Unusual trigonal-planar copper configuration revealed in the atomic structure of yeast copper-zinc superoxide dismutase.

The three-dimensional structure of yeast copper-zinc superoxide dismutase (CuZnSOD) has been determined in a new crystal form in space group R32 and refined against X-ray diffraction data using difference Fourier and restrained crystallographic refinement techniques. The unexpected result is that the copper ion has moved approximately 1 angstrom from its position in previously reported CuZnSOD models, the copper-imidazolate bridge is broken, and a roughly trigonal planar ligand geometry characteristic of Cu(I) rather than Cu(II) is revealed. Final R values for the two nearly identical room temperature structures are 18.6% for all 19 149 reflections in the 10.0-1.7 angstrom resolution range and 18. 2% for 17 682 reflections (F > 2 sigma) in the 10.0-1.73 angstrom resolution range. A third structure has been determined using X-ray data collected at -180 degrees C. The final R value for this structure is 19.0% (R(free) = 22.9%) for all 24 356 reflections in the 10.0-1.55 angstrom resolution range. Virtually no change in the positions of the ligands to the zinc center is observed in these models. The origin of the broken bridge and altered Cu-ligand geometry is discussed.

Crystallography, X-Ray↗
PubMed1993

Comparative evaluation of the clinical utility of three markers of ethanol intake: the effect of gender.

We evaluated three markers of ethanol intake [whole blood associated acetaldehyde (WBAA), serum beta-hexosaminidase, and gamma-glutamyl transpeptidase (GGT)] in four groups of subjects: teetotalers (n = 104), random insurance applicants or "normals" (n = 1,010), subjects enrolling in an alcohol treatment program or "alcoholics" (n = 31), and subjects attending outpatient drug/alcohol treatment follow-up clinics (n = 128). Significant differences (p < 0.004 for each assay and each comparison) were found in the mean values between teetotalers and normals and normals and alcoholics. Male teetotalers and normals had significantly (p < 0.002) higher levels of WBAA than females of the same group. Male normals had significantly higher levels of GGT than females (p < 0.001). GGT increased with age in the normal population into the fifth decade and decreased thereafter. WBAA was the most sensitive assay with 97% of alcoholics having values above the 99th percentile for the teetotaler population (vs. 66% for serum beta-hexosaminidase and 70% for GGT). None of the alcoholic subjects had values for all three assays below the 99th percentile for teetotalers compared with 21% of those in follow-up and 72% of normals. We conclude that WBAA appears to be the best of the three markers studied and that measurement of multiple markers for ethanol use appears clinically useful and incremental.

Acetaldehyde↗
PubMed1993

In vivo rectal inflammatory mediator changes with radiotherapy to the pelvis.

In vivo changes in the rectal values of eicosanoid inflammatory mediators induced by pelvic radiotherapy were measured to study the pathophysiology of the early radiation bowel reaction. Ten patients having pelvic radiotherapy, aged 57 to 78, had rectal dialysis. Values of the eicosanoids leukotriene B4 (LTB4), thromboxane B2 (TXB2), and prostaglandin E2 (PGE2) were measured before radiotherapy, at the end of radiotherapy, and at least four weeks after radiotherapy. Values of LTB4 rose with radiotherapy from 0.21 ng.ml-1 (median) to 1.14 ng.ml-1 (p = 0.012); PGE2 rose from 0.60 ng.ml-1 to 1.58 ng.ml-1 (p = 0.038), and TXB2 rose from 0.365 ng.ml-1 to 1.6 ng.ml-1 (p = 0.005). The rise in eicosanoid inflammatory mediators may have an important role in the pathophysiology of the early radiation bowel reaction.

Aged↗
PubMed1989

Response of plasma prorenin and active renin to chronic and acute alterations of renin secretion in normal humans. Studies using a direct immunoradiometric assay.

We employed a novel immunoradiometric assay to measure plasma levels of active renin and prorenin in physiologic and pharmacologic studies designed to characterize renin biosynthesis and processing in response to both chronic and acute stimuli of renin secretion in normal human subjects. Stimulation of renin secretion with prolonged dietary sodium restriction or amiloride resulted in marked increases in the plasma levels of prorenin, active renin, and plasma renin activity (PRA); suppression of renin secretion with indomethacin resulted in parallel decreases in prorenin, active renin, and PRA. In contrast, acute stimulation with upright activity or administration of an angiotensin-converting enzyme inhibitor, which increased active renin and PRA from 2- to 15-fold, had no effect on prorenin levels. Based on studies in cultured human juxtaglomerular tumor cells, it has been proposed that prorenin is secreted constitutively whereas active renin is stored in and released from secretory granules through a regulated pathway. Our studies are consistent with such a model: the parallel changes in active renin and prorenin with experimental maneuvers of long duration suggest that both the constitutive and regulated pathways are altered under these conditions. The increase in active renin levels in the absence of a change in prorenin that occurs in response to acute stimuli presumably represents the release of preformed active enzyme that is stored in secretory granules.

Adult↗
PubMed1987

Lactoferrin derived from neutrophils inhibits the mixed lymphocyte reaction.

The effects of the products of phagocytosing neutrophils on lymphocyte transcriptional activity have been investigated using allogeneic mixed lymphocyte cultures (MLC). When MLCs are grown crowded in round-bottomed wells, uptake of tritiated uridine is inhibited by the presence of neutrophil products. Similarly, inhibitory activity is shown by purified lactoferrin. The inhibitory factor released by neutrophils is positively identified as lactoferrin, since its activity is lost in the presence of specific antibody. In addition, inhibitory activity is lost when lactoferrin is removed by a monoclonal antibody (MoAb) column and is recovered with lactoferrin from the column. The active form of lactoferrin carries iron and the apoprotein is inactive. MLCs crowded in round-bottomed wells take up considerably more uridine than when spread in flat-bottomed wells, and it is this enhanced transcriptional activity that is inhibited by neutrophil-derived lactoferrin. Enhanced uridine uptake by crowded cultures is due to factors that can be transferred in the supernatants to promote uridine uptake by spread cultures. Neutrophil lactoferrin inhibits both production and effect of the transferable factor(s).

Dose-Response Relationship, Drug↗
PubMed1985

The effect of surgical gowns made with barrier cloth on bacterial dispersal.

A dispersal chamber (body box) technique has been used to compare bacterial dispersal from the skin of subjects carrying out a stepping test under controlled conditions while wearing four differing garment systems namely: basic underwear, cotton 'blues' (standard pyjama style jacket and trousers for men or dress for women), ankle socks, boots for men and shoes for women, mask and theatre hat; the basic set covered with a cotton gown; the basic set covered by a gown with a front made from GORE-TEX fabric in which an expanded polytetrafluoroethylene membrane is sandwiched between layers of woven or knitted polyester; the basic set covered with a fully enclosed suit of the same fabric. A slit sampler was used to measure the number of bacteria liberated in a downward current of air. Six subjects (three female and three male) were studied. Males liberated more bacteria. Covering the 'blues' with a cotton gown increased the bacterial count; a gown of the new material reduced the increase by 50%, and the suit cut the dispersal to virtually zero. Preliminary work suggests that GORE-TEX garments survive laundering better than cotton, and may be cost-effective, but are not yet as comfortable. Research is presently in progress to improve this aspect.

Bacteria↗
PubMedDate not supplied

Comparative analysis of below-knee prosthetic socket liner materials.

Four materials used in lining prosthetic sockets were compared for their potential usefulness in below-knee applications. Tests carried out included determinations of resistance to compression, resistance to flexural abrasion and coefficients (static and dynamic) of friction. These tests were designed, respectively, to assess changes occurring during end-use brought about by extensive application of compressive or shear force, and to predict the ability to retain contact with the body and socket. Of the four materials in the study (Bock-Lite, Pedilin, polyurethane and silicone), Bock-Lite and silicone had high compression resistance, Bock-Lite had good resistance to flexural abrasion, and polyurethane and silicone had high coefficients of frictional resistance. Thus, Bock-Lite will be the most durable of the four materials but, since it had the lowest frictional coefficient, it may slip in use. Conversely, silicone and polyurethane, which will be retained in position more easily, are easily torn or compressed, so are likely to need replacement more frequently.

Artificial Limbs↗