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M Klein

Publications and source records attributed to M Klein.

At least 55 records · Page 3Linked to original sources
PubMed2001

Polymicrobial polyarticular septic arthritis: a rare clinical entity.

Polymicrobial polyarticular septic arthritis is a rare clinical entity, with only a few cases having been reported to date. We report a case due to Streptococcus pyogenes and Staphylococcus aureus in an IVDU, complicated by fatal streptococcal toxic-shock syndrome, and review the current literature. We conclude that whenever polymicrobial polyarticular septic arthritis is diagnosed, a high index of suspicion should be maintained for the detection of locally destructive infectious processes as well as systemic complications, and that a high mortality rate should be expected.

Adult↗
PubMed2001

Energy metabolism of cocks and broiler chickens fed on diets with different carbohydrate sources.

Energy balances of cocks and chickens were measured using the nitrogen-carbon-balance method. In Experiment 1 twelve adult White Leghorn cocks were fed alternately on a basal ration or on a supplemental ration composed of 75% basal diet and 25% carbohydrate source as a supplement. In Experiment 2 six groups of 12 male broiler chickens were fed successively on two diets each with different carbohydrate sources (40% of DM) and on two energy levels. The investigated carbohydrate sources were glucose, fructose, sucrose, maize starch, raw and steamed potato starch, dried sugar beet pulp, tapioca, wheat, maize, rye and barley. In both experiments the energy digestibility of the diets with raw potato starch, beet pulp and barley was significantly lower compared to the other diets. Digestibility of those ranged from 88 to 81%. By simple linear regression no significant differences in efficiency of utilisation of ME of the diets between the carbohydrate sources sugars, starches and cereal grains could be proved. The corresponding MEm values agreed very close among the diets (411 to 429 kJ.kg BW-0.75.d-1).

Animal Nutritional Physiological Phenomena↗
PubMed2001

The use of external radioactive markers in scintimammography.

In Tc-99m MIBI scintimammography, the exact localization of foci of increased tracer uptake or the exact anatomic correlation of palpated breast masses with a scintigraphic finding is difficult. The authors describe three patients with known or possible malignant breast lesions for whom the use of external radioactive markers successfully helped to provide this information, thus improving the diagnostic accuracy and guiding decision-making in the patients' treatment.

Adult↗
PubMed2001

Tc-99m mercaptoacetyltriglycine clearance: comparison of camera-assisted methods.

PURPOSE: To compare the accuracy of three camera-assisted methods for the measurement of Tc-99m mercaptoacetyltriglycine (MAG3) clearance. MATERIALS AND METHODS: MAG3 renal scintigraphy was performed in 21 adults with different degrees of renal function. Posterior views were obtained that included the heart and the kidneys in the camera field of view. The syringe for injection was imaged before and after injection. Blood samples were drawn 24 and 43 minutes after injection and plasma radioactivity was measured. Three camera-assisted techniques to measure MAG3 clearance were tested: 1) Biexponential fitting of the left ventricular curve, normalized to plasma activity at 24 minutes; 2) calculation of clearance by relating the integral of the plasma curve (normalized to plasma activity) to the kidney activity using the Rutland-Patlak space method; and 3) a regression equation measuring clearance from the percentage of the injected dose accumulating in the kidneys during the 1- to 2.5-minute period. The camera-assisted clearances were compared with the single-sample MAG3 clearances calculated using the Russell equation. Linear regression analysis was used to measure the correlation between the camera-based methods and the single-sample techniques. RESULTS: Correlation with r > 0.900 was found for all three techniques. The difference in correlation coefficients between the three methods was not significant; however, the regression line of method 3 was significantly closer to the line of identity (P = 0.005). CONCLUSION: Method 3 most closely fits the line of identity and is probably the most practical because no blood sample is needed.

Adult↗
PubMed2001

Toward a catalog of human genes and proteins: sequencing and analysis of 500 novel complete protein coding human cDNAs.

With the complete human genomic sequence being unraveled, the focus will shift to gene identification and to the functional analysis of gene products. The generation of a set of cDNAs, both sequences and physical clones, which contains the complete and noninterrupted protein coding regions of all human genes will provide the indispensable tools for the systematic and comprehensive analysis of protein function to eventually understand the molecular basis of man. Here we report the sequencing and analysis of 500 novel human cDNAs containing the complete protein coding frame. Assignment to functional categories was possible for 52% (259) of the encoded proteins, the remaining fraction having no similarities with known proteins. By aligning the cDNA sequences with the sequences of the finished chromosomes 21 and 22 we identified a number of genes that either had been completely missed in the analysis of the genomic sequences or had been wrongly predicted. Three of these genes appear to be present in several copies. We conclude that full-length cDNA sequencing continues to be crucial also for the accurate identification of genes. The set of 500 novel cDNAs, and another 1000 full-coding cDNAs of known transcripts we have identified, adds up to cDNA representations covering 2%--5 % of all human genes. We thus substantially contribute to the generation of a gene catalog, consisting of both full-coding cDNA sequences and clones, which should be made freely available and will become an invaluable tool for detailed functional studies.

3' Untranslated Regions↗
PubMed2001

Multiple lateral transfers of dissimilatory sulfite reductase genes between major lineages of sulfate-reducing prokaryotes.

A large fragment of the dissimilatory sulfite reductase genes (dsrAB) was PCR amplified and fully sequenced from 30 reference strains representing all recognized lineages of sulfate-reducing bacteria. In addition, the sequence of the dsrAB gene homologs of the sulfite reducer Desulfitobacterium dehalogenans was determined. In contrast to previous reports, comparative analysis of all available DsrAB sequences produced a tree topology partially inconsistent with the corresponding 16S rRNA phylogeny. For example, the DsrAB sequences of several Desulfotomaculum species (low G+C gram-positive division) and two members of the genus Thermodesulfobacterium (a separate bacterial division) were monophyletic with delta-proteobacterial DsrAB sequences. The most parsimonious interpretation of these data is that dsrAB genes from ancestors of as-yet-unrecognized sulfate reducers within the delta-Proteobacteria were laterally transferred across divisions. A number of insertions and deletions in the DsrAB alignment independently support these inferred lateral acquisitions of dsrAB genes. Evidence for a dsrAB lateral gene transfer event also was found within the delta-Proteobacteria, affecting Desulfobacula toluolica. The root of the dsr tree was inferred to be within the Thermodesulfovibrio lineage by paralogous rooting of the alpha and beta subunits. This rooting suggests that the dsrAB genes in Archaeoglobus species also are the result of an ancient lateral transfer from a bacterial donor. Although these findings complicate the use of dsrAB genes to infer phylogenetic relationships among sulfate reducers in molecular diversity studies, they establish a framework to resolve the origins and diversification of this ancient respiratory lifestyle among organisms mediating a key step in the biogeochemical cycling of sulfur.

Amino Acid Sequence↗
PubMed2001

Induction of neutralizing antibodies and gag-specific cellular immune responses to an R5 primary isolate of human immunodeficiency virus type 1 in rhesus macaques.

The ability to generate antibodies that cross-neutralize diverse primary isolates is an important goal for human immunodeficiency virus type 1 (HIV-1) vaccine development. Most of the candidate HIV-1 vaccines tested in humans and nonhuman primates have failed in this regard. Past efforts have focused almost entirely on the envelope glycoproteins of a small number of T-cell line-adapted strains of the virus as immunogens. Here we assessed the immunogenicity of noninfectious virus-like particles (VLP) consisting of Gag, Pro (protease), and Env from R5 primary isolate HIV-1(Bx08). Immunogens were delivered to rhesus macaques in the form of either purified VLP, recombinant DNA and canarypox (ALVAC) vectors engineered to express VLP, or a combination of these products. Seroconversion to Gag and Pro was detected in all of the immunized animals. Antibodies that could neutralize HIV-1(Bx08) were detected in animals that received (i) coinoculations with DNA(Bx08) and VLP(Bx08), (ii) DNA(Bx08) followed by ALVAC(Bx08) boosting, and (iii) VLP(Bx08) alone. The neutralizing antibodies were highly strain specific despite the fact that they did not appear to be directed to linear epitopes in the V3 loop. Virus-specific cellular immune responses also were generated, as judged by the presence of Gag-specific gamma interferon (IFN-gamma)-producing cells. These cellular immune responses required the inclusion of DNA(Bx08) in the immunization modality, since few or no IFN-gamma-producing cells were detected in animals that received either VLP(Bx08) or ALVAC(Bx08) alone. The results demonstrate the feasibility of generating neutralizing antibodies and cellular immune responses that target an R5 primary HIV-1 isolate by vaccination in primates.

Animals↗
PubMed2001

Changes in fatal and near-fatal asthma in an urban area of South Africa from 1980-1997.

Over the past two decades, changes in the health services designed to improve access to and quality of asthma care have occurred in South Africa. The aim of this study was to investigate the incidence of fatal and near-fatal asthma (NFA) from 1980-1997 in an urban part of South Africa. A retrospective analysis of fatal asthma and NFA in the Cape Town City Council area was performed. Mortality data were obtained from death notification records. Data on NFA were obtained from the records of patients admitted for asthma to intensive care units (ICUs) at major academic hospitals serving the area. There were 1,506 deaths (mean age 56 yrs) from asthma reported; 39 and 3% occurred in people under 55 and 15 yrs, respectively. Average annual asthma mortality rate (8.1 +/- 1.9 per 100,000 population) was highest amongst people of mixed race (10.1 +/- 2.0), followed by Blacks (6.8 +/- 3.1) and Whites (5.0 +/- 1.9, p<0.001). Asthma mortality declined by 0.28 deaths per 100,000 population per year; rates decreased in all ethnic groups. Most deaths (72.3%) were outside a health facility and a higher number of deaths occurred on weekends (223 deaths x day(-1)) than weekdays (207 deaths x day(-1), p=0.014). Paediatric asthma ICU admissions declined by 1.81 children yr(-1). The annual number of adults admitted to ICU for asthma, and the proportion requiring intermittent positive pressure ventilation did not change. These results indicate that the incidence of fatal and near-fatal asthma in this area has declined over the period and this may reflect improved asthma management. However, the relatively high asthma mortality rate in people of mixed race and the predominance of deaths outside health facilities and on weekends suggest problems with access to care.

Adolescent↗
PubMed2001

Increased expression of the vascular endothelial growth factor is a pejorative prognosis marker in papillary thyroid carcinoma.

Vascular endothelial growth factor (VEGF) is a potent stimulator of endothelial cell proliferation. It has been implicated in tumor growth of human thyroid carcinomas. Using the VEGF immunohistochemistry staining score, we correlated the level of VEGF expression with the metastatic spread of 19 cases of thyroid papillary carcinoma. The VEGF immunostaining score, ranging from 0-9, was determined as the multiplication of a percentage of labeled thyrocytes score (0, no labeling; 1, <30%; 2, 31--60%; 3, >61% of labeled thyrocytes) and an intensity score (0, no staining; 1, weak; 2, mild; 3, strong staining). The mean score +/- SD was 5.74 +/- 2.59 for all carcinomas. The mean score for metastatic papillary carcinoma was 8.25 +/- 1.13 vs. 3.91 +/- 1.5 for nonmetastatic papillary cancers (P < 0.001). By discriminant analysis, we found a threshold value of 6.0, with a sensitivity of 100% and a specificity of 87.5%. There were no statistical differences between metastatic and nonmetastatic carcinomas when age, tumor size, or thyroglobulin levels were considered. The VEGF immunostaining score seems to be a helpful marker for metastasis spread in differentiated thyroid cancers. An increased production of VEGF could assess an aggressive disease and be the hallmark of a trend to produce metastasis. We propose the VEGF immunostaining score as a marker for the prognosis in differentiated thyroid cancers. A value of 6 or more, should be considered as at high risk for metastasis threat, prompting the physician to institute a tight follow up of the patient.

Adolescent↗
PubMed2001

Lectin binding patterns of uterine glands in mares with chronic endometrial degeneration.

OBJECTIVE: To evaluate changes of glycoconjugate in uterine glands of endometrial tissues obtained from mares. ANIMALS: adult mares. PROCEDURE: Uterine biopsy samples were collected during the breeding season and analyzed histologically for signs of chronic endometrial degeneration. Stage of the estrous cycle was established, using clinical examination and determination of hormonal status. Uterine tissue samples were analyzed, using lectin histochemical and immunohistochemical techniques (estrogen and progesterone receptors). Connective tissues were stained to determine alterations of ground substance in periglandular fibrosis. RESULTS: Of 50 mares, 30 (60%) were classified as normal or having modest alterations, and 20 (40%) were classified as having moderate or severe endometrial degeneration. In normal equine endometrium, several lectins (Helix pomatia agglutinin, Lotus tetragonolobus agglutinin, Ricinus communis I agglutinin, Ulex europaeus agglutinin, and wheat germ agglutinin) bound to glycoconjugates of the luminal epithelium and openings of uterine glands. Lectin binding patterns of cystic dilated glands or fibrotic glands in endometrial samples were remarkably strong, whereas normal surrounding cells remained unstained. Lotus tetragonolobus lectin was not suitable for detecting endometrial alterations. Connective tissues stained with Alcian blue and results of Hale colloidal-iron binding revealed acidic ground substance in periglandular fibrosis. Estrogen and progesterone receptors were evenly distributed in healthy and affected endometrial samples. CONCLUSIONS AND CLINICAL RELEVANCE: Glycoconjugate patterns of uterine glands were altered in mares with chronic endometrial degeneration. Therefore, uterine secretions are likely to be altered. These changes are not induced by changes in content of estrogen and progesterone receptors in endometrial tissues.

Animals↗
PubMed2001

Aetiology and outcome of pneumonia in human immunodeficiency virus-infected children hospitalized in South Africa.

UNLABELLED: To determine the aetiology and outcome of pneumonia in human immunodeficiency virus (HIV)-infected children, we prospectively investigated 250 children hospitalized with pneumonia who were known or clinically suspected to be HIV-positive, or who required intensive care support in Cape Town, South Africa. Blood culture, induced sputum or bronchoalveolar lavage, nasopharyngeal aspirate and gastric lavage were performed. Of the total, 151 children (60.4%) were HIV-infected. Pneumocystis carinii pneumonia (PCP), occurring in 19 (7.6%) children (15 HIV-positive), was the AIDS-defining infection in 20.3%. The incidence and type of bacteraemia (14.3%) were similar in HIV-positive and HIV-negative patients; S. pneumoniae (5%) and S. aureus (2%) were the predominant isolates. Sputum or BAL cultures yielded bacteria in 145 of 243 (60%) specimens; viruses were cultured in 37 (15.2%). Bacterial prevalence (including M. tuberculosis in 8%) and anti-microbial resistance did not differ by HIV status except for S. aureus which was more common in HIV-infected children. Thirty-one (20%) HIV-positive and 8 (8%) HIV-negative children died [RR 1.16 (95% CI 1.05-1.28), p=0.008]; using multiple logistic regression, PCP was the only risk factor for mortality (p = 0.03). CONCLUSION: In South Africa, PCP is an important AIDS-defining infection in children; bacterial pathogens occur commonly and with a similar prevalence in HIV-positive and HIV-negative children hospitalized for pneumonia. HIV-infected children with pneumonia have a worse outcome than HIV-negative patients.

Female↗
PubMed2001

Bolus high dose interleukin-2 for the treatment of malignant melanoma.

BACKGROUND: High dose interleukin-2 therapy, administered in bolus, is considered to be a reasonable treatment option in a selected group of patients with metastatic malignant melanoma. OBJECTIVES: To present our experience using this mode of therapy in 21 patients with metastatic melanoma. MATERIALS AND METHODS: The 21 patients in our study group comprised 13 men and 8 women with a mean age of 46 years (range 29-63). Their metastatic disease was present in all extracranial sites, dermal and sub-dermal metastases being the most common (15 patients had at least one site, in addition to other locations of metastases). Patients with intracranial disease were excluded due to the poor effectivity of IL-2 at this site. Treatment comprised a course of 2 weeks of therapy with a 1 week rest interval between. Radiological and physical evaluation was performed 6-8 weeks after the first course. If a response was achieved a second course of therapy was given. Patients received up to 14 planned doses of IL-2 in each week, 720,000 IU/kg of IL-2 per dose i.v. in 15 minutes. All treatments were given in the surgical ward, and only one patient was hospitalized in the intensive care unit. RESULTS: Of the 21 patients, one had a complete response that has lasted for 17 months and 5 patients had a partial response (range 3 months to 3 years). One patient died during treatment, and one patient who refused further treatment because of no response died a few days after completion of treatment. Prior to therapy three of the responders had received autologous vaccines with good immunological response (P = 0.115). Toxic side effects were significant, but they were treated successfully with no residual damage. CONCLUSIONS: High dose IL-2 can be administered safely in a surgical department. The response rates achieved in this series justify the use of high dose IL-2 in a selected group of patients. To improve response rates, a combination of autologous vaccines prior to high dose IL-2 may be recommended.

Adult↗
PubMed2001

Computer-guided surgery utilizing a computer-milled surgical template.

The primary objective of implant placement is to support prosthetic restorations that return patients to proper oral form, function, and aesthetics. Since correct implant placement can be a technique-sensitive process, it is performed in conjunction with various diagnostic and guidance procedures. For accurate diagnosis, radiographic templates, computed tomography scans, and surgical simulation software are unparalleled. This article demonstrates the manner by which computer-guided surgery and computer-milled surgical templates can enable precise implant placement for the entire implant team.

Alveolar Process↗
PubMed2001

Blood product use during routine open heart surgery: the impact of the centrifugal pump.

A prospective randomized study was done including 1,000 patients undergoing routine open heart surgery. Patients were randomly assigned to either a roller pump or a BioMedicus centrifugal pump with identical extracorporeal circuits. There were no significant differences between study groups. Actual blood products transfused and predicted transfusion requirements (using Cardiac RiskMaster) were examined as was chest tube drainage (CTD). The predicted transfusion requirement was 885 of 1,000 patients. Transfusions were required by 472 of 1,000. Risk factors as significant predictors of increased CTD and use of blood products were emergency surgery status, increased cross-clamp time, and higher predicted risk of mortality. The only significant predictor of decreased CTD was the use of a centrifugal pump. Predictors of increased length of stay were myocardial infarction, preoperative urea, age, and massive transfusion. Data provide evidence that use of the centrifugal pump improves patient outcomes by decreasing CTD and decreasing the requirements for transfusion, which results in a shorter hospital stay.

Blood Transfusion↗
PubMed2001

[Sentinel lymph node biopsy in breast cancer: a validation study and preliminary results].

INTRODUCTION: Sentinel lymph node biopsy (SLNB) has been recently proven to be an accurate staging method for breast cancer, replacing axillary lymph node dissection (ALND) in selected cases. We present our initial experience and the process of introduction and implementation of SLNB in a University Hospital setting. MATERIAL AND METHODS: 46 SLNB were performed in 42 consecutive female patients with invasive breast cancer. Treatment included 0.4mCi-2mCi of Tc-99m rhenium colloid injected either 2 hours before surgery (0.4 mCi) or the night before surgery (2 mCi). Four milliliters of Patent Blue V were injected peritumoral 10 minutes prior to skin incision in all patients. Following SLNB all women underwent subsequent ALND. Sentinel nodes were processed both with multiple (10-15) H&E sections and immunohistochemistry with cytokeratin antibodies stain. RESULTS: Blue dye, isotope or the combination of both identified 43/46 (93%) of the sentinel lymph nodes. ALND was performed only unilaterally in 4 patients with bilateral breast cancer bringing the total evaluable SLNB to 39. In the 39 patients in whom the sentinel node was successfully identified and underwent ALND, the SLNB was true positive (TP) in 17/39 (44%) true negative (TN) in 20/39 (51%) and false negative in 2/39 [(5%), both T2 lesions] with overall accuracy of 95%. In the last 10 cases all sentinel nodes were successfully identified with 70% TP and 30% TN. CONCLUSIONS: Experience with at least 30-40 consecutive cases for safe implementation of SLNB in clinical practice. Specific training and dedication is required for the entire team involved, including surgeons, nuclear medicine physicians and technicians and pathologists.

Adult↗
PubMed2001

Impact of a first-year primary care experience on residency choice.

We designed a retrospective cohort study of first-year medical students to assess the impact of a community-based primary care course, Introduction to Primary Care (IPC), on residency choice. In the group that took IPC (n=282), 48.2% entered generalist residencies (internal medicine, pediatrics, family medicine, or medicine/pediatrics), compared to 38.2% in the group that wanted IPC (n=398) and 39.6% in the group that did not want IPC (n=245). Controlling for gender, students who took IPC had a 40% higher odds of selecting a generalist residency than those who wanted to take IPC (odds ratio [OR], 1.42; 95% confidence interval [CI], 1.04 to 1.95). There was no difference between those who wanted IPC and those who did not (OR, 1.08; CI, 0.78 to 1.52). The community-based primary care experience was positively associated with students' selection of generalist residencies.

Adult↗