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K Katz

Publications and source records attributed to K Katz.

At least 37 records · Page 2Linked to original sources
PubMed1998

Weight-bearing patterns on the knees of preterm infants.

In this study we present a method of monitoring the forces under the knees of preterm infants lying in the prone position. Dual force sensing resistor transducers, connected to optically-isolated amplifiers, were used to monitor the forces. A thermistor airflow sensor was used for the parallel monitoring of the respiratory signal. The measurements were made on ten preterm infants. The average forces were 0.51 and 0.50 N for the left and right knees, respectively. In the frequency domain, the basic harmonic of the force traces was 1.27 Hz approximately, corresponding to the respiratory rhythm. Additional, smaller harmonics, were detected in the force traces at 2.54 and 3.81 Hz. A rather notable power signal could also be seen around 0.1 Hz. The results obtained indicate that the system developed is highly sensitive for providing data on the amplitudes, periods and sequences of oscillations and symmetry of load bearing in preterm infants. Knowledge of the normal and abnormal reaction force patterns may assist in the early diagnosis of abnormal neurodevelopment.

Humans↗
PubMed1997

The effect of the treatment of hypothyroidism and hyperthyroidism on plasma lipids and apolipoproteins AI, AII and E.

OBJECTIVE: Although lipid abnormalities are well described in hypothyroidism, effects on apolipoproteins are less well understood. The aim of this study was to examine the effects of thyroid dysfunction on plasma lipids and apolipoproteins. DESIGN: A prospective study of lipids and apolipoproteins before and after treatment of hypothyroidism and hyperthyroidism. PATIENTS: Eighteen patients with hypothyroidism and 5 patients with hyperthyroidism were included. MEASUREMENTS: Plasma cholesterol, triglycerides, HDL cholesterol, apo AI, apo AII, and apo E were measured before and after treatment of the thyroid abnormality. RESULTS: Total and HDL cholesterol, apo AI and apo E decreased with treatment of hypothyroidism, while triglycerides and apo AII levels were unchanged. The total/HDL cholesterol and LDL/HDL cholesterol ratios also decreased with treatment of hypothyroidism. In contrast, treatment of hyperthyroidism was associated with an increase in total and HDL cholesterol, and apo AI. Triglycerides, apo AII and Apo E were unchanged by treatment of hyperthyroidism. The total/HDL cholesterol and the LDL/HDL cholesterol ratios increased with treatment of hyperthyroidism. CONCLUSIONS: Hypothyroidism and hyperthyroidism have opposite effects on plasma lipids and apolipoproteins. In hypothyroidism, total and HDL cholesterol, total/HDL cholesterol ratio, apo AI and apo E are elevated. The increase in apo AI without a concomitant increase in apo AII suggests selective elevation of HDL2. In contrast, hyperthyroidism is associated with decreased total and HDL cholesterol, total/HDL cholesterol ratio, and apo AI levels. These effects are reversible with treatment of the underlying thyroid disorder.

Adult↗
PubMed1997

Adolescents' access to reproductive health and family planning services in Dakar (Senegal).

This paper analyses the issue of adolescents' access to family planning services and information on reproductive health. The data used in this paper are a part of a broader study conducted in 1995 in Dakar (Senegal) by the Committee for Studies on Women, Family and Environment in Africa (COSWFEVA/CEFFEVA) and Family Health International. The findings present information on adolescents' perceptions of premarital sexual activity and contraceptive use and the different types of barriers to access to family planning, using data obtained primarily from focus group discussions with adolescents 16 to 20 years old and a mystery client study. In this approach, 12 of the adolescents participating in the focus group discussions visited clinics as clients and requested contraceptive methods or information. The results indicate that adolescents did not approve of premarital sexual relations, were less likely to approve of contraceptive use by adolescents than by married men and women, and felt embarrassed to go to the services. They were also disappointed by the providers' reception and response to their needs. The content of the counselling offered by the providers was moralistic, encouraging girls to abstain from having sexual intercourse until marriage. The discussions of the findings related adolescents' and providers' attitudes to the socio-cultural context in which adolescent sexuality takes place. In this context, sexuality is closely linked to marriage and childbearing, which affects the impact of classical programs on adolescent health. Alternative solutions such as the life skills development approach could be promoted in order to reach both in-school and out-of-school adolescents.

Adolescent↗
PubMed1996

Clinical outcomes of two early postpartum IUD insertion programs in Africa.

Postpartum IUD insertion programs are new to Africa and few have been carefully evaluated. Also, data on the clinical outcomes of postpartum IUD insertions using the Copper T 380A IUD are sparse. Therefore, we conducted a study to evaluate introductory postpartum IUD programs using the Copper T 380A IUD in Kenya and Mali. Postpartum IUD acceptors in Kenya (n = 224) and Mali (n = 110) were interviewed at baseline and at 1, 3, amd 6 months after delivery. We compared expulsion, medical removal, and discontinuation rates by insertion characteristics in each country. Six-month cumulative expulsion rates were lower for immediate insertions (those within 10 minutes of placental delivery) than for late insertions (generally between 10 minutes and 72 hours after placental delivery) in both Kenya (0.01 vs 0.05) and Mali (0.15 vs 0.27). Medical removals occurred in 1% and 7% of Kenyan and Malian acceptors, respectively, while pelvic infections were rare in both countries (< or = 2%). Differences in 6-month cumulative discontinuation rates between immediate and late insertions were not significant in either Kenya (0.05 vs 0.07) or in Mali (0.24 vs 0.32). This study suggests that postpartum IUD insertions can be performed safely with acceptable expulsion rates in African settings. Previous studies of other IUDs showed that expulsion rates are lower for immediate insertions compared with late postpartum insertions. This study suggests that these findings can be extended to the Copper T 380A IUD.

Adult↗
PubMed1996

Effective treatment of painful bone crises in type I gaucher's disease with high dose prednisolone.

In type I Gaucher's disease, episodes of severe disabling bone pain, the so called bone crises, may be resistant to all analgesics, including narcotics. The demonstration of subperiosteal oedema on magnetic resonance imaging (MRI) led to an attempt to use steroids to relieve the oedema and thereby the pain. On eight occasions, five patients with documented bone crises received conventional dose steroids (20 mg/m2/day) with considerable shortening of the attacks. On six occasions five further patients received high dose methylprednisolone (30 mg/kg intravenously or 1 g/m2 orally daily for two days), which was followed by oral prednisone for three to five days on the last four occasions. In this later group, pain relief was evident within several hours. Three treatments were given on an ambulatory basis. The MRI scan of one of these patients showed no subperiosteal fluid collection five days after high dose steroids had been started, and on subsequent x ray examination, there was no periosteal elevation. This treatment should be considered in cases of Gaucher's disease with bone crises.

Adolescent↗
PubMed1996

The natural history of osteonecrosis of the femoral head in children and adolescents who have Gaucher disease.

We reviewed the cases of eight patients (thirteen hips) with Gaucher disease who had had osteonecrosis of the femoral head and had been managed with bed rest and non-weight-bearing with crutches only in the symptomatic stage of the bone crisis. The mean age of the patients at the onset of the first crisis in each hip was ten years (range, six to fourteen years). The mean age at the most recent follow-up examination for the six living patients (ten hips) was twenty-three years (range, nineteen to thirty-three years). The Mose rating was good for one hip, fair for two, and poor for seven. Despite the over-all unfavorable radiographic ratings, the six patients were asymptomatic and did not need assistance with daily activities. There is no known treatment that effectively prevents the development of deformities of the femoral head. Thus, we recommend symptomatic management for osteonecrosis of the femoral head in Gaucher disease with bed rest and analgesics followed by non-weight-bearing on the involved limb, if it makes the patient more comfortable, during the symptomatic stage of bone crisis.

Adolescent↗
PubMed1996

Acceptability and discontinuation of Depo-Provera, IUCD and combined pill in Kenya.

This paper reports on a prospective study conducted between June 1990 and June 1992 to determine method acceptability, user satisfaction and continuation rates for three highly effective and reversible contraceptive methods currently available in Kenya: the CuT 380A (IUCD), the injectable, Depo-Provera and the low-dose oral contraceptive pill, Microgynon. A non-randomised sample of volunteer participants was used. One thousand and seventy-six users were followed up for a period of one year or up to the time of discontinuation of the method, whichever came earlier. Analysis revealed method specific differences in users' characteristics. The OC users were younger and had fewer children than the IUCD or Depo-Provera users. The Depo-Provera users were older, and had the largest family sizes. Many OC users (almost 40%) were single, while almost three-quarters of IUCD and Depo-Provera users were married. IUCD users were also more educated compared to OC and Depo-Provera users. Survival analysis was used to calculate cumulative life table discontinuation rates by method for the 12 month period. Discontinuation rates were highest for OC users (80%) and lowest for IUCD users (20%) and intermediate for Depo-Provera users (39%). Ninety percent of OC and Depo-Provera users and 86% of IUCD users said they were satisfied with their respective methods. While OCs are among the most popular family planning methods in Kenya, they are also one of the most problematic, while IUCD has the fewest compliance problems. Service providers need to address the issue of high discontinuation rates among the young OC users.

Adolescent↗
PubMed1995

Prognostic factors for survival in patients with metastatic renal cancer treated with biological response modifiers.

PURPOSE: Clinical characteristics prognostic of survival in patients with metastatic renal cell carcinoma treated with biological response modifiers are poorly understood. Understanding these prognostic features may help with better stratification of patients in clinical trials and define further appropriate treatment for each prognostic subgroup. MATERIALS AND METHODS: A retrospective study of 84 patients with recurrent or metastatic renal cancer was conducted to identify prognostic factors for survival in patients who received biological response modifiers (alpha-interferon, beta-interferon, gamma-interferon and interleukin-2). RESULTS: Univariate analysis identified Eastern Cooperative Oncology Group (ECOG) performance status (1 versus 0, p < 0.001), bone metastasis (p = 0.008), recent weight loss (greater than 10% of total body weight versus no loss, p = 0.028), history of nephrectomy (no versus yes, p = 0.025), recurrence at the renal bed (p = 0.043) and sarcomatoid histology (yes versus no, p < 0.001) as important prognostic indicators. Multivariate analysis of prognostic factors in this patient population indicated that ECOG performance status, sarcomatoid histology and bone metastasis were most significant, while other factors were less significant (p > 0.05) after adjusting for ECOG performance status and sarcomatoid histology. Based on the total positive number of 5 risk factors defined previously the study population separates into 3 risk groups, with a median survival from the low to high risk groups of 14.4, 10.9 and 1.3 months, respectively. Prognostic scores based only on ECOG performance status, sarcomatoid histology and bone metastasis allowed for stratification of our patients into 3 distinct groups with median survivals of 18.6, 8.4 and 3.8 months, which were also predictive of survival (p < 0.05). CONCLUSIONS: Risk factors of ECOG performance status, sarcomatoid histology, bone metastasis, history of nephrectomy, recent weight loss and recurrence at the renal bed are predictive of survival in patients treated with biological response modifiers. In addition to previous findings of prognostic factors in renal cancer patients treated with chemotherapy, we identified sarcomatoid histology as an important risk factor in patients treated with biological response modifiers.

Bone Neoplasms↗
PubMed1994

The pattern of bone disease in transfusion-dependent thalassemia major patients.

Twenty-eight patients with thalassemia major were treated with frequent blood transfusions for 10-25 years. Eleven (39%) had radiographic signs of osteoporosis, and four (14%) presented with fractures. Keeping hemoglobin level above 9.0 g/dl reduced osteoporosis and the incidence of fractures but did not prevent them. Osteonecrosis of the femoral head and distal femur, not previously reported, was noted in two patients.

Adolescent↗
PubMed1994

Aminohydroxy propylidene bisphosphonate (APD) treatment improves the clinical skeletal manifestations of Gaucher's disease.

OBJECTIVE: To evaluate the long-term effects and safety of aminohydroxy propylidene bisphosphonate (APD) treatment on the frequency and severity of the clinical skeletal manifestations of Gaucher's disease. METHODOLOGY: Five adolescents who suffered from recurrent bone crisis episodes and atraumatic bone fractures due to Gaucher's disease were treated with APD for 14 to 83 months. RESULTS: During the 6 years before treatment, the patients suffered from 6 to 17 bone crisis episodes, or 1 to 2.8 episodes per patient per year. Three patients were free from bone crisis episodes during 14 to 32 months of ADP treatment, while two patients had two such episodes during 60 and 83 months of APD treatment (these represent a decrease in bone crisis episodes from 1 and 2.8 per year to 0.4 and 0.3 per year, respectively). Although four patients suffered from 1 to 3 atraumatic bone fractures during the 6 years preceding treatment (a total of 10 fractures), only one patient sustained a fracture on APD treatment (total of 219 months of treatment). Using APD was not associated with clinical side effects, biochemical aberrations, significant changes in liver and kidney function, or changes in serum levels of the hormones regulating mineral metabolism. In all patients, a band-like metaphyseal sclerosis appeared on radiography of the long bone. However, APD did not interfere with bone growth. CONCLUSIONS: The marked clinical improvement in the clinical skeletal manifestations of Gaucher's disease and the absence of toxic side effects in adolescent patients treated with APD support previous findings in three adult patients on the efficacy of APD and indicate possibilities for its use in inducing prolonged remissions in affected patients.

Adolescent↗
PubMed1993

Spinal involvement in children and adolescents with Gaucher disease.

Nineteen patients with type I Gaucher disease with spinal involvement first diagnosed during childhood, were followed for 2 to 24 years (average 9 years), and their clinical and radiologic history reviewed. Patients presented with three types of pain: mild pain that was defined as nonspecific, severe pain due to bone crisis, and pain associated with vertebral collapse. Collapse of vertebra occurred gradually anywhere along the thoraco-lumbar spine, and usually more than one vertebra was involved. In three patients, rectangular collapse was noted. Six patients suffered from central vertebra collapse, and two from anterior wedge compression. Further vertebral collapse with signs of root and cord compression developed in three patients as they grew. Awareness to the possibility of progressive vertebral collapse and periodic follow-up might prevent severe complications.

Adolescent↗
PubMed1993

Upper limb involvement in patients with Gaucher's disease.

Seventeen of 55 children and adolescents with Gaucher's disease presented with upper limb pain. Seven had nonspecific pain, 11 had bone crisis, and 2 had arthritis symptoms in the proximal interphalangeal joints. X-ray films of both hands showed osteopenia and thinning of the cortex in half of the patients.

Adolescent↗
PubMed1993

Genu valgum in children who received renal transplant.

In 19 children who received renal transplants, 6 developed genu valgum one to two years after the transplantation. Except for one patient, biochemical blood and urine parameters were normal and bone radiograph showed no signs of renal osteodystrophy during this period. Two patients had bilateral varus supracondylar osteotomy, and in one patient medial hemistapling of the distal femur was performed.

Adolescent↗
PubMed1993

Improved results in osteogenic sarcoma 1973-79 vs. 1980-86: analysis of results from a single center.

Analysis of treatment results in osteogenic sarcoma patients with classical limb primary tumors and without metastasis at diagnosis or major protocol violations showed improved prognosis with a minimum follow-up of over 5.5 years when divided by years of treatment for all event-free survivors. Twelve patients treated in 1980-86 had a 5-year disease-free survival of 67% and 9 treated in 1973-79 had a 5-year disease-free survival of 33% (P = 0.0368). The improvement appeared to reflect the increase in the intensity of the chemotherapy utilized. Definitive surgery, amputation or limb salvage did not affect the outcome. With these surgical approaches the disease-free survival was 67% and 60% respectively.

Adolescent↗
PubMed1992

Long-term follow-up of partial splenectomy in Gaucher's disease.

Seven children with Gaucher's disease who underwent partial splenectomy were followed for 7 to 8 years. None of the children had systemic sepsis or symptoms related to liver enlargement. Bone crisis occurred in only two children who had experienced bone crisis prior to partial splenectomy. This contrasts with the development of bone crises in five of six children who underwent total splenectomy at a similar age and who had previously been free of bone symptoms. Partial splenectomy should be regarded as a temporary solution in the treatment of hypersplenism and the mechanical compression related to the huge spleen. In 71% of the patients, massive enlargement and a severe to moderate degree of pancytopenia occurred again after 3 to 8 years; total splenectomy was required in three patients.

Adolescent↗
PubMed1992

Non-specific X linked mental retardation with aphasia exhibiting genetic linkage to chromosomal region Xp11.

A new type of non-specific X linked mental retardation is described in a three generation family. The three affected males had severe mental retardation (IQ 20 to 30), mutism, growth failure, frequent infections, seizures, and the following minor anomalies: brachycephaly, frontal hair whorl, square face, large mouth, thick lips, and prognathism. There was not a characteristic facies. Normal laboratory studies on the proband included a karyotype with fragile X screening, skeletal survey, blood amino acid, urine organic acid, and HGPRT levels. Linkage analysis was performed with 10 X chromosome DNA probes of which probe DXS255 at chromosomal region Xp11.22 gave a maximal two point lod score of 2.10 if phase was inferred and 1.20 if it was not. Crossovers were shown with probes mapping to regions Xp22, Xp21, and Xq28. Comparison of these patients with 80 X linked causes of mental retardation, including 41 which might be classified as 'non-specific', showed no other disorders compatible with the phenotypic and linkage data.

Abnormalities, Multiple↗