Biomedical subjects

M Shoukri

Publications and source records attributed to M Shoukri.

16 recordsLinked to original sources

PubMed2005

Fine-needle aspiration of the testis in azoospermic men: the value of measuring serum follicle stimulating hormone and testicular size.

Testicular fine-needle aspiration biopsy (FNAB) is used as a primary tool in assessing azoospermic infertile men in our institution. If the FNA is negative for sperm, a subsequent testicular biopsy specimen and wet preparation are obtained with possible immediate fertilization. To our knowledge, the value of these techniques in the context of testicular size and serum levels of follicle stimulating hormone (FSH) has not been explored. We reviewed 453 FNA biopsies of the testis performed for the identification of sperm in infertile azoospermic males between 1999 and 2000. We identified cases that had all three procedures (FNA, wet preparation and biopsy) performed. These were the patients that were compared for testicular size using Seager orchiometry and serum levels of FSH. Of the 453 FNAs reviewed, 128 (21%) had all three procedures performed. Seventy-two cases (56%) were negative in all three tests, 26 (20%) cases were positive in all tests, and 30 cases (23%) had different results. These 30 cases were excluded. The testicular size in the negative group ranged from 4 to 16 ml (median, 10 ml) and the positive group had testicular sizes ranging from 10 to 25 ml (median, 15 ml; P = 0.0001). The negative group had serum FSH levels ranging from 3 to 52 IU/l (median, 19 IU/l) whereas the positive group had serum levels ranging from 3 to 26 IU/l (median, 10 IU/l; P = 0.0001). Our findings suggest that in infertile azoospermic men, a testicular size of <10 ml combined with a serum FSH level of >19 IU/l, the chances of retrieving sperm are minimal using all three diagnostic modalities. The use of this cutoff point would lead to a 30-50% reduction in the number of procedures performed. This reduction would have a significant impact on the management of these patients with a significant decrease in cost, logistics, and patient anxiety.

Adult↗

PubMed2005

Long-term course and predictive factors of elevated serum thyroglobulin and negative diagnostic radioiodine whole body scan in differentiated thyroid cancer.

UNLABELLED: Following the initial management, some patients with differentiated thyroid cancer (DTC) develop a state of high thyroglobulin (Tg) and negative diagnostic radioactive iodine (RAI) whole body scan (DxWBS). The predisposing factors and outcome of this condition are unclear. In this study, our objectives were to determine the predictive factors for the development of high Tg and negative DxWBS (Tg+/scan-) and to study the long-term course of the disease in patients with this condition. METHODS: We, retrospectively, reviewed the medical records of a cohort of 105 non-selected DTC patients (26 males and 79 females; median age 37.7 yr, range 7-72). None of these patients had positive Tg antibodies or distant metastases. All Tg levels were obtained off thyroid hormone therapy. At the first follow-up visit after RAI ablation (13 +/- 7.6 months), patients were classified into those with low Tg (<2 ng/ml off L-T4) and negative DxWBS (control group) and those with high Tg ( > or = 22 ng/ ml off L-T4) and negative DxWBS (Tg+/scan- group). Using univariate and multivariate logistic regression analyses, we evaluated a number of parameters (see results) for their association with the development of Tg+/scan-. In addition, the long-term course of the disease in Tg+/scan- group was analyzed. RESULTS: In univariate analysis, the following factors were found to be significantly associated with Tg+/scan-: perithyroidal tumor extension (p=0.025), soft tissue invasion (p=0.001), cervical lymph node metastases (p=0.014) and Tg level before RAI ablation (p=0.015). In multivariate analysis, only soft tissue invasion remained significantly associated with Tg+/scan- [p 0.001, odds ratio, 15.6 (95% Cl, 2.96-82.06)]. Age, sex, duration of goiter before surgery, pressure symptoms, tumor size, tumor multifocality, lymph nodedissection at initial surgery, tumor-node-metastasis (TNM) stage, and RAI ablative dose were not associated with Tg+/ scan-. In 53 patients with Tg+/scan-, 42 cases were followed without any therapeutic intervention; over a median follow-up of 71.6 months (range, 13-144.7), 31 cases had a spontaneous remission and 11 cases continued to have a persistent disease (Tg > or = 2 ng/ml, negative DxWBS, and no palpable disease or distant metastases); Tg declined from 9.32 +/- 9.91 ng/ml at first visit after RAI ablation to 1.59 +/- 5.39 ng/ml at last visit (p<0.0001). In the other 11 cases of Tg+/scan- group, one or more therapeutic interventions (RAI, surgery, or external radiotherapy) were undertaken. Over a median follow-up of 98.4 months (range, 6-147), Tg decreased from 110.2 +/- 147.5 to 23.5 +/- 41.2 ng/ml (p 0.026); 4 cases achieved remission, 5 cases continued to have persistent disease, and 2 cases had progression of their disease, which led to their death. CONCLUSION: Soft tissue invasion on original surgery strongly predicts the development of Tg+/scan- in DTC patients. The long-term course of the disease is mostly favorable especially when the Tg level is only modestly elevated.

Adolescent↗

PubMed2004

Loss to follow-up of patients with malignant lymphoma.

Loss to follow-up (LTFU) in cancer patients is a serious problem, yet there is little data on this and on the underlying reasons. Of 144 paediatric and 431 adult patients with lymphoma diagnosed in 1997/1998 at King Faisal Specialist Hospital and Research Center, Riyadh (KFSHRC), 30% and 48.5%, respectively, were LTFU after 4 years (excluding patients known to have died). In 2001-2002, 196 paediatric and adult lymphoma patients at KFSHRC were enrolled in a prospective study in which explanations were obtained in detail for non-attendance at follow-up appointments (No Show). Sixteen months after commencement of the study, 49 patients were No Show, because of patient-based communication problems (20), transportation problems (8), patient not contactable (18), and personal reasons (3). In addition, patients were recorded incorrectly as No Show through hospital/patient communication problems. The No Show patients, especially the 23 who failed to keep a second appointment, are identifiable as potential LTFU during the 3 years in which this cohort will be followed. This study and, we suggest, other studies on LTFU should stimulate interest in this issue, in the predisposing factors, and in strategies to address them.

Adult↗

PubMed2003

Primary diagnosis and REAL/WHO classification of non-Hodgkin's lymphoma by fine-needle aspiration: cytomorphologic and immunophenotypic approach.

The Revised European American lymphoma (REAL) and World Health Organization (WHO) classification of non-Hodgkin's lymphoma (NHL) relies on the constellation of cytologic, phenotypic, genotypic, and clinical characteristics of NHL. For the most part, the classification does not rely on architectural pattern for classification of neoplasms. This classification makes it possible to diagnose and classify lymphomas by fine-needle aspiration (FNA). In this study, we attempted to evaluate the accuracy of FNA in diagnosing and classifying NHL within the context of the REAL/WHO classifications. Cases included only those in which FNA was the primary diagnosis, followed by a surgical biopsy for confirmation. Flow cytometry (FCM) for phenotyping was carried out whenever material was available. Two groups of pathologists were identified. Group A consisted of pathologists with background training in cytopathology and/or hematopathology (three pathologists). Group B consisted of experienced surgical pathologists with no training in cytopathology and/or hematopathology (four pathologists). Seventy-four cases were included in the study. FCM phenotyping was performed in 53 cases (71%). Large cell lymphoma constituted 63% of the cases. The remaining lymphomas included Burkitt's, small lymphocytic, lymphoblastic, follicle center cell, Ki-1, mantle cell, marginal zone, and natural killer cell lymphoma. The diagnosis of lymphoma was rendered for all cases. The correct classification was seen in 63% of the cases. Classification was more accurate in immunophenotyped than in nonimmunophenotyped cases (84% vs 33%; P = 0.00004). Group A pathologists showed higher incidence of proper classification than group B (80% vs 56%; P = 0.046). The diagnosis and classification of NHL can be achieved in a large number of cases on FNA material. This accuracy can be increased if cytomorphologic criteria are established for different entities of NHL aided by FCM for phenotyping.

Biopsy, Needle↗

PubMed2002

Prognostic factors and treatment modalities in uterine sarcoma.

The aim of this study was to identify the impact of various prognostic factors in the management of uterine sarcoma. Fifty-nine patients with uterine sarcoma were treated at King Faisal Specialist Hospital and Research Center between 1980 and 1997. Forty-three patients (73%) were treated by total abdominal hysterectomy and bilateral salpingo-oophorectomy, 7 (12%) total abdominal hysterectomy and bilateral salpingo-oophorectomy with sampling of pelvic lymph nodes, and 9 (15%) had biopsy only. Nine patients received adjuvant treatment; five had radiation therapy (XRT), two had chemotherapy, one had combined XRT and chemotherapy, and one received hormonal treatment. Leiomyosarcoma cases accounted for 42% of all the uterine sarcomas, carcinosarcoma cases for 34%, and endometrial stromal sarcoma (ESS) for 24%. Fifty (85%) patients had pathologic grade II and III tumor, with only 9 patients grade I. Twenty-seven patients (46%) were classified surgically as stage I, 7 (12%) as stage II, 17 (29%) as stage III, and 8 (13%) had stage IV tumor. Recurrences developed in 34 patients (71%). The 5- and 10-year overall actuarial survival for all patients was 42%, and the corresponding relapse-free survivals for those who achieved complete response after primary treatment (48 patients) were 27% and 20%. On the univariate analysis, grade I tumors (p = 0.04), ESS (p = 0.02), nonmetastatic stage (p = 0.05), and negative peritoneal cytology (p = 0.04) were associated with better overall survival. Factors associated

Adolescent↗

PubMed2001

Long-term results of pulmonary balloon valvulotomy in adult patients.

BACKGROUND AND AIM OF THE STUDY: The study aim was to define the long-term outcome of pulmonary balloon valvulotomy (PBV) in adult patients. METHODS: PBV was performed in 87 patients (46 females, 41 males; mean age 23+/-9 years; range: 15-54 years) with congenital pulmonary valve stenosis (PS). Intermediate follow up catheterization (mean 14.6+/-5.0; range: 6-24 months) was performed after PBV in 53 patients. Clinical and Doppler echocardiography examinations were carried out annually in 82 patients (mean 8.0+/-3.9; range: 2-15 years). RESULTS: There were no immediate or late deaths. The mean catheter peak pulmonary gradient (PG) before and immediately after PBV, and at intermediate follow up was 105+/-39, 34+/-26 (p <0.0001) and 17+/-14 (p <0.0001) mmHg, respectively. The corresponding values for right ventricular (RV) pressure were 125+/-38, 59+/-21 (p <0.0001) and 42+/-12 (p <0.0001) mmHg, respectively. The infundibular gradients immediately after PBV and at intermediate follow up were 31+/-23 and 14+/-9 mmHg (p <0.0001), whilst cardiac index improved from 2.68+/-0.73 to 3.1+/-0.4 l/min/m2 (p <0.05) at intermediate follow up. Doppler PG before PBV and at intermediate and long-term follow up were 91+/-33 (range 36-200) mmHg, 28+/-12 (range 10-60) mmHg (p <0.0001) and 26+/-11 mmHg (p = 0.2), respectively. New pulmonary regurgitation (PR) was noted in 21 patients (25%) after PBV. Five patients (6%) with a suboptimal result (immediate valve gradient > or =30 mmHg) developed restenosis and underwent repeat valvulotomy 6-12 months later using a larger balloon, and with satisfactory outcome. Moderate to severe tricuspid regurgitation (TR) in seven patients regressed after PBV. CONCLUSION: The long-term results of PBV in adults are excellent, with regression of concomitant, severe infundibular stenosis and/or severe TR. Hence, PBV should be considered as the treatment of choice for adult patients with PS.

Adolescent↗

PubMed2000

Age pattern of mortality in eight breeds of insured dogs in Sweden.

The objective of this study was to use several methods to describe the age patterns for risk of death in selected breeds of dogs insured for life in a Swedish animal-insurance company in 1996. Data on eight breeds were analyzed for age at death (including euthanasia). If dogs left the insurance for reasons other than death, they were regarded as censored. Dogs were only insured up to 10 years of age. Four analytical approaches were used. First, descriptive statistics of age distributions (e.g. breed-specific median ages at death, breed- and age-specific mortality risks) were computed. Second, age-specific estimates of survival were calculated using the formula: survival=(1-risk(age<1 year))(1-risk(age 1<2 year))... (1-risk(age 9<1 0 year)). Third, Cox regression (proportional-hazards model) was used to estimate survival and hazard functions. Finally, hierarchically coded Poisson regression was used to determine age-specific cut-points in the risk of death. The hazards from Cox and the incidence-density rates from the hierarchically coded models were transformed to estimates of risk: risk=1-exp¿-(hazard)¿ or 1-exp¿-(incidence-density rate)¿. The breeds studied were Beagle, Bernese mountain dog, Boxer, Cavalier King Charles spaniel, Drever, German shepherd dog, Mongrel and Poodle, together representing over 50000 dogs each year. The yearly breed-specific mortality risk varied between 1.7% (Poodle) and 6.5% (Bernese mountain dog). In all breeds, the risk of death increased with age but the pattern varied by breed. The probability of survival at 5 years of age varied between 94% (Cavalier King Charles spaniel and Poodle) and 83% (Bernese mountain dog, Drever, German shepherd dog) and the survival at 10 years between 83% (Poodle) and 30% (Bernese mountain dog). The survival estimates from Cox and those derived using the combined-risk formula were similar. The cut-point risk estimates provided a simplified picture of when the risk of death changed significantly compared to previous age categories. As anticipated, breeds differed widely in survival up to 10 years of age and there were marked differences in age patterns of mortality. The implications of these findings should be considered in multivariable analyses, where the confounding effect of age is often controlled for using a single age variable common to several breeds.

Age Distribution↗

PubMed2000

Sero-prevalence of granulocytic Ehrlichia spp. and Borrelia burgdorferi sensu lato in Swedish dogs 1991-94.

In Sweden, 2 tick-borne zoonotic diseases, granulocytic ehrlichiosis and borreliosis, are frequently diagnosed in dogs, using serological assays. The aims of this study were to determine the sero-prevalences of antibodies to Ehrlichia spp. and Borrelia burgdorferi sensu lato during 1991-94 in dogs, not clinically suspected to be infected with either of the 2 agents. Samples (n = 611) were selected from a serum bank using a systematic sampling strategy, stratified across the 4-y period. The stored sera had originally been submitted in order to verify or rule out infection with Sarcoptes scabiei. The overall sero-prevalence for Ehrlichia spp. was 17.7% and for Borrelia burgdorferi sensu lato 3.9% (n = 588). Only a few dogs in the northern part of Sweden were sero-positive for Ehrlichia spp. and none were positive for Borrelia burgdorferi sensu lato. An increased sero-prevalence of Ehrlichia spp. was seen during the years studied. The sero-prevalence of Ehrlichia spp. varied with season. Sero-positivity to both agents increased with age. Both diseases are considered zoonotic, and the increase in sero-prevalence of Ehrlichia spp. over the years may reflect the degree of infection in ticks and may have implications for human health.

Age Factors↗

PubMed2000

Spatial distribution of cannibalism mortalities in commercial laying hens.

The distribution of cannibalism cases in a flock of 19,776 Babcock White Leghorns was monitored from 21 to 54 wk of age. The hens were kept in a single-floor house consisting of four banks of two-deck stair-step cages. Each of the 4,944 cages held four hens at a density of 152 cm(2) (60 inches(2)) per hen. Each cage was assigned a number from 1 to 4,944, and each dead bird was tagged according to its cage of origin. Dead birds were collected daily, kept in a freezer, and necropsied weekly. Farm personnel routinely transferred a live hen from an end cage to a cage where a mortality had occurred. The cause of death, age, cage number, and cage location were recorded for each dead hen. Of the 1,173 hens that died during the study period, 253 (21.6%) died from egg peritonitis, 184 (15.7%) from hypocalcemia, 167 (14.1%) from cannibalism, 164 (14%) from neoplastic disease, and the rest from various other causes. Cannibalism cases were analyzed statistically for clustering. Cannibalism was defined as death from tissue trauma and hemorrhage inflicted by cage mates. A spatial analysis showed that cannibalism is not a random event but one that occurs in clusters. The incidence of cannibalism was also found to be significantly higher on the top rows of cages as compared with the bottom rows.

Age Factors↗

PubMed1999

Associations between stomach cancer incidence and drinking water contamination with atrazine and nitrate in Ontario (Canada) agroecosystems, 1987-1991.

BACKGROUND: Nitrate and atrazine are two chemicals that are heavily used in certain sectors of agriculture. They are suspected to be associated with the development of certain types of tumours. METHODS: Existing data were obtained on the incidence of specific types of cancers, contamination of drinking water with atrazine and nitrate, and related agricultural practices for the 40 ecodistricts in the province of Ontario. The data were merged into a georelational database for geographical and statistical analyses. Weighted (by population size) least squares regression analyses were conducted while controlling for confounding socioeconomic and lifestyle factors. Maximum likelihood spatial error models were estimated when least square regression error terms were found to be spatially autocorrelated using the Moran's I statistic. RESULTS: Atrazine contamination levels (range 50-649 ng/l, maximum acceptable concentration [MAC] = 60000 ng/l) were positively associated (P < 0.05) with stomach cancer incidence and negatively associated with colon cancer incidence. Nitrate levels, (range 0-91 mg/l, MAC = 10 mg/l) were negatively associated with stomach cancer incidence. CONCLUSION: The associations found at the ecodistrict level, both positive and negative, if confirmed by other studies, raise serious questions about maximum allowable limits for atrazine, as well as possibilities of complex trade-offs among disease outcomes, and interactions of biophysical and social mechanisms which might explain them. Although the negative associations appear to have no direct biological explanations, such counter-intuitive outcomes may occur in complex systems where social and biological variables interact.

Adult↗

PubMed1999

Modeling the effect of an outbreak of bovine herpesvirus type 1 on herd-level milk production of Dutch dairy farms.

One of the impacts of disease is its effect on milk production. In the present study the effect of an outbreak of bovine herpesvirus type 1 on milk production at the herd level of certified bovine herpesvirus type 1-free dairy farms was modeled. The objective was to study several linear models to quantify the effects of a bovine herpesvirus type 1 outbreak on milk production accounting for the repeated measurements and incorporating our assumptions about the most likely duration of effects of this virus. Because milk production is measured at regular intervals, the data consisted of repeated measurements at the herd and cow levels. A marginal model, a subject-specific random-effect model, and a transition model were developed. The effect of a bovine herpesvirus type 1 outbreak was statistically significant in the random-effect model, and this model fitted the investigated farms best. However, a transition model might be a better model for generalizing the results to the whole population of Dutch dairy farms. The effect of a bovine herpesvirus type 1 outbreak on milk production derived from the random-effect model amounted to, on average, a loss of 0.92 kg of milk per cow per day during a period of 9 wk. The milk production loss varied from almost none to 2 kg of milk per cow per day. This reduction resulted in an average loss of Dfl 372 (Dfl1 = $US $0.50) with lower and upper confidence limits of, respectively, Dfl 12 and Dfl 730 per bovine herpesvirus type 1 outbreak.

Animals↗

PubMed1999

Analyte comparisons between 2 clinical chemistry analyzers.

The purpose of this study was to assess agreement between a wet reagent and a dry reagent analyzer. Thirteen analytes (albumin, globulin, alkaline phosphatase, alanine aminotransferase, amylase, urea nitrogen, calcium, cholesterol, creatinine, glucose, potassium, total bilirubin, and total protein) for both canine and feline serum were evaluated. Concordance correlations, linear regression, and plots of difference against mean were used to analyze the data. Concordance correlations were excellent for 8 of 13 analytes (r > or = 0.90); the correlations for albumin, potassium, and calcium were clinically unreliable. The linear regression analysis revealed that several analytes had slopes significantly different from unity, which was likely related to methodological differences. Compared to the wet reagent analyzer, the dry reagent analyzer showed excellent agreement for alkaline phosphatase, alanine aminotransferase, amylase (feline), urea nitrogen, cholesterol, creatinine, glucose, total bilirubin (canine), and total protein. However, it showed only slight to substantial agreement for amylase (canine), calcium, albumin, potassium, and total bilirubin (feline).

Animals↗

PubMed1998

Review of inference procedures for the interclass correlation coefficient with emphasis on applications to family studies.

Recent theory and methodology for inferences concerning the interclass correlation coefficient are reviewed, focusing on the case of a single individual in one class and a variable number of individuals in the other. Topics discussed include point and interval estimation, as well as significance-testing, with emphasis on application to data arising from family studies.

Data Interpretation, Statistical↗

PubMed1998

Analysis of survivorship after displaced abomasum is diagnosed in dairy cows.

The objective of this study was to analyze the survivorship of dairy cows after displaced abomasum was diagnosed. Survivorship from the calving preceeding diagnosis of displaced abomasum to removal from the herd was investigated for cows that were diagnosed with displaced abomasum compared with herdmates. For cows that were diagnosed with displaced abomasum, factors that affected survivorship from the diagnosis of the disease to removal were investigated. Data from a total of 135 cows that had been diagnosed with displaced abomasum and 373 controls matched by herd and lactation number were available from a database at the University of Guelph. The hazard rate of removal from the herd was estimated using proportional hazard regression adjusted for intraherd correlation. Diagnosis of displaced abomasum significantly increased the hazarad rate of removal from the herd. For cows that were diagnosed with displaced abomasum the hazard rate of removal increased as parity increased. However, the hazard rate decreased with recurrent displaced abomasum and with higher days in milk at diagnosis of the disease. Although the 305-d milk production of cows that were diagnosed with displaced abomasum was lower during the lactation when the disease was diagnosed, 305-d milk production was not associated with removal of cows with that disease from the herd. Milk production during subsequent lactations did not differ between cows that were diagnosed with displaced abomasum and control cows. Low milk production during the subsequent lactations increased the hazard of removal of cows with that disease from the herd.

Abomasum↗

PubMed1992

Argyrophilic nucleolar organizer regions in breast carcinoma. Correlation with DNA flow cytometry, histopathology, and lymph node status.

Argyrophilic nucleolar organizer regions (AgNOR) have been correlated with proliferative activity of neoplasms. Increased AgNOR may reflect increased proliferative activity of cells or ploidy. To explore this hypothesis, 41 breast carcinomas were processed for AgNOR silver staining and DNA flow cytometry. AgNOR counts were expressed as mean AgNOR/nucleus and percentage of tumor cells with more than five AgNOR/nucleus. The first count was designated mean AgNOR or mAgNOR, and the second count was designated AgNOR proliferative index or pAgNOR. Using Mantel-Haensel statistical analysis, carcinomas that exhibited mAgNOR of 2.4 or more had a high likelihood of aneuploidy (P less than 0.0001), an S-phase fraction of more than 5.8% (P less than 0.003), or a diameter greater than 2 cm (P less than 0.007). In addition, tumors with pAgNOR of 8% or more showed a statistically significant correlation with aneuploidy (P less than 0.004), tumor grade (P less than 0.04), and a more significant one with high S-phase fraction (P less than 0.0001). No significant correlation was obtained between pAgNOR and tumor size or lymph node status. These data indicate that AgNOR quantitation reflects changes in DNA ploidy and cell proliferation. They also suggest that the mean AgNOR counts correlate best with the DNA mass or ploidy and that the frequency of cells with higher AgNOR count best reflects proliferative activity or S-phase fraction.

Aneuploidy↗

PubMed1992

Classification of 1,198 cases of bovine lymphoma using the National Cancer Institute Working Formulation for human non-Hodgkin's lymphomas.

A retrospective histologic study was made of 1,198 cases of bovine lymphoma using the National Cancer Institute Working Formulation for human non-Hodgkin's lymphoma. This classification scheme was found to be readily applicable to bovine lymphoma. Most of the cell types described in the National Cancer Institute Working Formulation occurred in this series of bovine lymphomas, but the distribution of cell types varied markedly compared to that of human beings. Eighty-nine percent (1,067/1,198) of bovine lymphomas were high-grade tumors. The diffuse large cell type and its cleaved variant comprised 65.9% of all bovine lymphomas. Similar to the dog, but in marked contrast to human beings where at least 34% of non-Hodgkin's lymphomas were follicular, follicular tumors were found to be extremely rare in cattle (0.3% or 4/1,198). The prevalence of cell types varied significantly between the enzootic and sporadic lymphomas. The cleaved variant of the diffuse large cell type constituted 38% (406/1,072) of enzootic lymphomas versus 14% (18/126) of sporadic lymphomas. The mitotic index (100 x oil immersion field, 175 microns in diameter) of enzootic lymphomas (3.72 +/- 0.06, mean +/- standard error) was significantly greater than the mitotic index of sporadic lymphomas (2.82 +/- 0.17). We concluded that the cleaved variant of the diffuse large cell type with high mitotic index is characteristic of enzootic lymphoma. This characteristic high-grade cell type may be a consequence of the viral etiology of the enzootic form of bovine lymphoma.

Age Factors↗