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Biomedical subjects

M B Zaman

Publications and source records attributed to M B Zaman.

At least 19 recordsLinked to original sources
PubMed2006

MELD score as a prognostic model for listing acute liver failure patients for liver transplantation.

OBJECTIVES: The King's College Hospital (KCH) criteria are widely used for listing patients with acute liver failure (ALF) for liver transplantation (LT). Recent reports have suggested that the Model for End-Stage Liver Disease (MELD) score may be useful in assessing prognosis in ALF (nonparacetamol). This study compares prognostic accuracy of the two systems in patients with paracetamol (POD)-induced ALF treated in this unit. METHODS: Seventy-two patients (average age 38 years; F:M ratio 2:1) admitted from 1994 to 2005 with POD-related ALF were studied. Clinical and biochemical parameters were recorded. The effect of applying a MELD score of greater than 30 as listing criteria for LT was calculated and compared with the KCH criteria. Outcomes were defined as LT, death, or full recovery. RESULTS: Thirty-one patients (43%) recovered with medical therapy, 29 (40%) patients died, and 12 (17%) underwent LT. Sixty five percent of patients had a MELD > 30 and therefore could potentially be listed on admission; however, using KCH criteria only 24% patients were listed immediately. Sensitivity and negative predictive value of MELD was higher then KCH; however, we found KCH to have much higher specificity and positive predictive value. CONCLUSION: MELD has higher sensitivity and negative predictive value for POD-induced ALF than the KCH criteria. However, the high false-positive rate associated with MELD limits its clinical utility. The high negative predictive value of MELD score may allow it to be used in conjunction with KCH criteria to avoid unneeded LT in patients who will likely recover spontaneously.

Adult↗
PubMed2001

Crystal engineering using anilic acids and dipyridyl compounds through a new supramolecular synthon.

The anilic acids, 2,5-dihydroxy-1,4-benzoquinone (1a), 2,5-dibromo-3,6-dihydroxy-1,4-benzoquinone (bromanilic acid; 1b), 2,5-dichloro-3,6-dihydroxy-1,4-benzoquinone (chloranilic acid; 1c), and 2,5-dicyano-3,6-dihydroxy-1,4-benzoquinone (cyananilic acid; 1d), were cocrystallized with rigid organic ligands containing two pyridine rings, 2,4-bipyridine (2a), 4,4'-bipyridine (2b), 1,2-bis(2-pyridyl)ethylene (3a), 1,2-bis(4-pyridyl)ethylene (3b), 2,2'-dipyridylacetylene (4a), 3,3'-dipyridylacetylene (4b), and 4,4'-dipyridylacetylene (4c). Fourteen complexes 5-18 were obtained as single crystals, and their crystal structures were successfully determined by X-ray analysis. All complexes except those with 2a are 1:1 and are composed of an infinite linear or zigzag tape structure, the formation of which is ascribed to intermolecular O-H...N, N(+)-H...O, or N(+)-H...O(-) hydrogen bonds or a combination of these between the anilic acids and the dipyridyl compounds. In the complexes 5 and 6, no infinite tape structure is observed although the molecular units connected by a similar hydrogen-bonding pattern are formed. For the 1:1 complexes, we have found two types of stacking arrangements, segregated stacks (7, 9, 12-15, 18) and alternated ones (8, 10, 11, 16, 17). In the complexes of 1c with the series of dipyridylacetylenes 4 (14, 15, 17), the neutral, dication, and monocaction states are formed depending on the nitrogen positions, which can be attributed to the different basicity of the pyridyl groups.

Journal Article↗
PubMed2001

Linear hydrogen-bonded molecular tapes in the cocrystals of squaric acid with 4,4'-dipyridylacetylene and 1,2-bis(4-pyridyl)ethylene.

The title compounds, 4,4'-(ethyne-1,2-diyl)dipyridinium bis(squarate), C(12)H(10)N(2)(2+).2C(4)HO(4)(-), and 4,4'-(ethene-1,2-diyl)dipyridinium bis(squarate), C(12)H(12)N(2)(2+).2C(4)HO(4)(-), are isomorphous and crystallize in space group P-1. The cocrystals contain linear hydrogen-bonded molecular tape structures along the [120] direction. The squarate monoanions form a ten-membered dimer linked by two intermolecular O-H.O hydrogen bonds. Each component molecule forms a segregated stack along the c axis. The bond lengths of the squarate monoanion indicate delocalization of the enolate anion.

Journal Article↗
PubMed1994

Dietary beta carotene and lung cancer risk in U.S. nonsmokers.

BACKGROUND: Approximately 15% of all lung cancer deaths in the United States (about 22,350 deaths annually) may not be directly attributable to active cigarette smoking. Consumption of beta carotene, which is derived almost exclusively from intake of fruits and vegetables, has been associated with a reduced risk of lung cancer in smokers. However, studies examining this association in nonsmokers, particularly nonsmoking men, are limited. PURPOSE: The purpose of this study was to examine whether dietary factors including beta carotene and retinol are associated with a reduced risk for lung cancer in nonsmoking men and women. METHODS: A population-based, matched case-control study of lung cancer in nonsmokers was conducted in New York State from 1982 to 1985. Dietary interviews were completed for 413 individually matched case-control pairs of subjects. To determine whether the relationship between dietary intake from specific food groups and lung cancer differed by type of interview, smoking history, sex, age, or histologic type, we examined data on the case-control pairs from each subgroup separately. The intake of beta carotene and retinol was calculated as the weighted sum of the monthly frequencies of consumption of food items containing these nutrients, where the weights correspond to the nutrient content of a typical portion of the food items. RESULTS: Consumption of greens (P for trend < .01), fresh fruits (P for trend < .01), and cheese (P for trend < .05) was associated with a significant dose-dependent reduction in risk for lung cancer, whereas consumption of whole milk (P for trend < .01) was associated with a significant dose-dependent increase in risk. Use of vitamin E supplements was also protective (odds ratio = 0.55; 95% confidence interval [CI] = 0.35-0.85). Increased consumption of the following food groups was associated with a reduction in risk among females: vegetables (P for trend < .025), raw fruits and vegetables (P for trend < .005), and dairy products (P for trend < .025). In males, increased consumption of raw fruits and vegetables was associated with a reduced risk for lung cancer (P for trend < .005). Dietary beta carotene (OR = 0.70; 95% CI = 0.50-0.99), but not retinol (OR = 0.98; 95% CI = 0.82-1.17), was significantly associated with risk reduction. CONCLUSIONS: This is the largest study to date of dietary factors and lung cancer in nonsmokers; results suggest that dietary beta carotene, raw fruits and vegetables, and vitamin E supplements reduce the risk of lung cancer in nonsmoking men and women.

Adult↗
PubMed1994

Treatment and prognosis in bronchial carcinoids involving regional lymph nodes.

From 1953 to 1992, 25 patients were surgically treated for bronchial carcinoids with metastases to regional lymph nodes (N1 or N2). The tumors were located centrally, involving main or lobar bronchi in 12 patients and were peripheral in 13. Histologically, 12 of the carcinoids were classified as typical and 13 as atypical (neuroendocrine carcinoma). Pneumonectomy was performed in 11 patients, sleeve lobectomy in one, lobectomy in seven and bilobectomy in six. A formal mediastinal lymph node dissection was done in 20 patients. At final staging, 10 had N1 disease and 15 had N2. No adjuvant treatment was given to the 10 patients with N1 disease. External radiation therapy was given after the operation to 9 of 15 patients with N2 disease. The overall 5-year survival (Kaplan-Meier) was 75% (median 62 months). No difference in survival was found between patients with N1 or N2 disease. However, survival and recurrence rate differed between typical and atypical carcinoids. In typical carcinoids, the 5-year survival was 92% and, in atypical carcinoids, it was 60% (p = 0.02). We conclude that complete resection for bronchial carcinoids results in long-term survival despite the presence of regional lymph node metastases. Recurrence appears to depend more on cell type than nodal status. Postoperative radiation therapy does not appear to be beneficial.

Adolescent↗
PubMed1993

Pathologic complete response in advanced non-small-cell lung cancer following preoperative chemotherapy: implications for the design of future non-small-cell lung cancer combined modality trials.

PURPOSE: This report determines the incidence of pathologic complete response in patients with locally advanced non-small-cell lung cancer (NSCLC) treated with mitomycin, vinca alkaloid, and high-dose cisplatin (MVP) chemotherapy, and estimates the effect of MVP on survival. PATIENTS AND METHODS: We have identified and reviewed the course of 21 patients with advanced NSCLC who achieved a pathologic complete response following a median of three preoperative MVP combination chemotherapy courses including vinblastine or vindesine, cisplatin (120 mg/m2), and mitomycin (n = 19). RESULTS: All patients had a major objective response following preoperative chemotherapy and nine (43%) had a clinical complete response. Nine patients with pathologic complete responses were among 73 entered on a preoperative chemotherapy program, yielding an incidence estimate of 12% (95% confidence interval, 6% to 22%). The median survival duration for all 21 patients has not been reached. The median follow-up duration is now 68 months (range, 17 to 109). Survival estimates are 90% at 1 year, 62% at 3 years, and 54% at 5 years. Nine patients have relapsed with initial sites of recurrence as follows: brain (n = 5), other systemic sites (n = 3), and locoregional (n = 1). One patient died in the postoperative period. Eleven patients remain disease-free and all have excellent functional status. CONCLUSION: We have observed pathologic complete responses in approximately 12% of advanced NSCLC patients treated with preoperative MVP chemotherapy. These pathologically determined responses were seen only in patients with major objective responses clinically. Pathologic complete response predicts excellent survival and functional level and should be considered a major end point in the evaluation of preoperative chemotherapy programs.

Adult↗
PubMed1991

Bilateral bronchoalveolar lavage in the diagnosis of opportunistic pulmonary infections.

To further improve the diagnostic value of bronchoscopy in the immunosuppressed population presenting with diffuse pulmonary infiltrates, we prospectively investigated the utility of bilateral bronchoalveolar lavage (BAL). We performed 62 bronchoscopies on 52 immunosuppressed patients. Of the 52 patients, 33 had pulmonary infections. The yield for Pneumocystis carinii pneumonia on bilateral BAL was 94 percent (31/33), compared to the 84 percent (51/61) previously obtained with unilateral BAL in our institution. The recovery of P carinii was unilateral in four of five patients without AIDS and in four of 26 patients with AIDS. Transbronchial biopsy gave a yield of 85 percent (11/13). In ten patients with definitive cytomegalovirus (CMV) pneumonia, recovery of CMV by combined culture and cytology was 100 percent. Of nine bronchoscopies with positive cytology for CMV, five showed cytopathologic changes in the BAL from both sides and four in the BAL from one side only. No complications were seen in the 14 patients with thrombocytopenia or the five patients receiving mechanical ventilation. Our findings indicate that bilateral BAL significantly increases the yield for recovery of P carinii (p less than 0.02) and CMV (p less than 0.001) in immunosuppressed patients.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Pulmonary cytology.

Cytomorphologic criteria for the diagnosis and classification of primary pulmonary carcinomas are described and illustrated. Helpful hints for the differential diagnosis from benign entities and tumors and the cytologic limitations are stated. The fact that pulmonary cytologic interpretations must be made in the light of accurate clinical presentation is emphasized.

Biopsy, Needle↗
PubMed1991

Extrathoracic metastatic malignant thymoma. Diagnosis by aspiration cytology.

A fine-needle aspirate from a hepatic mass in a 65-year-old white man was examined. The patient had a history of histologically confirmed thymoma with metastases in multiple thoracic sites. The smears showed a dimorphic population of epithelial cells and lymphocytes, characteristic of thymoma. The resemblance of the cytologic pattern to the primary neoplasm and positive reactivity with various immunohistochemical agents peculiar to thymomas confirmed the diagnosis. Aspiration cytology has been described in the diagnosis of primary thymoma. To our knowledge, this is the second reported case of a cytologic diagnosis of metastatic thymoma and the first one with immunohistochemical studies.

Biopsy, Needle↗
PubMed1990

Lung cancer and exposure to tobacco smoke in the household.

BACKGROUND: The relation between passive smoking and lung cancer is of great public health importance. Some previous studies have suggested that exposure to environmental tobacco smoke in the household can cause lung cancer, but others have found no effect. Smoking by the spouse has been the most commonly used measure of this exposure. METHODS: In order to determine whether lung cancer is associated with exposure to tobacco smoke within the household, we conducted a population-based case--control study of 191 patients with histologically confirmed primary lung cancer who had never smoked and an equal number of persons without lung cancer who had never smoked. Lifetime residential histories including information on exposure to environmental tobacco smoke were compiled and analyzed. Exposure was measured in terms of "smoker-years," determined by multiplying the number of years in each residence by the number of smokers in the household. RESULTS: Household exposure to 25 or more smoker-years during childhood and adolescence doubled the risk of lung cancer (odds ratio, 2.07; 95 percent confidence interval, 1.16 to 3.68). Approximately 15 percent of the control subjects who had never smoked reported this level of exposure. Household exposure of less than 25 smoker-years during childhood and adolescence did not increase the risk of lung cancer. Exposure to a spouse's smoking, which constituted less than one third of total household exposure on average, was not associated with an increase in risk. CONCLUSIONS: The possibility of recall bias and other methodologic problems may influence the results of case-control studies of environmental tobacco smoke. Nonetheless, our findings regarding exposure during early life suggest that approximately 17 percent of lung cancers among nonsmokers can be attributed to high levels of exposure to cigarette smoke during childhood and adolescence.

Adolescent↗
PubMed1990

Aerosolized pentamidine: effect on diagnosis and presentation of Pneumocystis carinii pneumonia.

STUDY OBJECTIVE: To determine the effect of previous aerosolized pentamidine therapy on diagnosis and presentation of Pneumocystis carinii pneumonia. DESIGN: A retrospective study. SETTING: A tertiary care hospital. PATIENTS: Fifty-two consecutive patients with P. carinii pneumonia and underlying infection with the human immunodeficiency virus (HIV) who had bronchoscopy. Twenty-one patients who were on aerosolized pentamidine therapy served as the study group. Thirty-one patients who had not received the drug served as the control group. MEASUREMENTS AND MAIN RESULTS: The yield of bronchoalveolar lavage for P. carinii pneumonia was 62% for the study group and 100% for the control group (P less than 0.05). This lower yield was significant for the subset of patients having their first episode of P. carinii pneumonia. The yield of transbronchial biopsy was similar for both groups of patients (81% compared with 84%). The yield of bronchoscopy was not influenced by use of zidovudine. Review of lavage specimen slides suggested that there may be fewer organisms present in patients receiving aerosolized pentamidine. An atypical roentgenographic presentation of upper lobe predominant infiltrates was seen in 38% of the study patients and 7% of the control patients. In addition, pneumothoraces and cystic changes were also frequently seen in the study patients. Gallium scans, when done, were also atypical in the study group. Markers of the severity of disease, however, were similar in both groups. CONCLUSION: The yield of bronchoalveolar lavage for P. carinii pneumonia in HIV-infected patients is lower in patients receiving aerosolized pentamidine. Unusual roentgenographic presentations and atypical gallium scans are also found in this setting.

Aerosols↗
PubMed1989

The effect of tumor size and tumor cell DNA content on the survival of patients with stage I adenocarcinoma of the lung.

Tumor size at resection and flow cytometric (FCM) DNA distribution of 93 pathologically confirmed AJC Stage I adenocarcinomas of lung were compared with survival. All lung cancers had been treated by lobectomy and mediastinal lymph node dissection at this Institution, and the pathology of all cases was reviewed. Median tumor size was 2.5 cm. FCM DNA assays were carried out on the formalin-fixed, paraffin-embedded tumor tissue. Seventy-nine (85%) of the tumors were aneuploid and 14 were diploid. There was no significant difference in survival between patients with diploid and aneuploid tumors. The DNA index, proliferation fraction, and fraction of aneuploid cells also had no effect on survival. However, patients with tumors smaller than 3 cm in diameter had a significantly better prognosis than those with larger tumors. Thus, in Stage I adenocarcinoma of lung, tumor size but not cellular DNA content distinguishes subgroups with favorable versus unfavorable prognosis.

Adenocarcinoma↗
PubMed1988

The effects of preoperative chemotherapy on the resectability of non-small cell lung carcinoma with mediastinal lymph node metastases (N2 M0).

We have defined "clinical N2" disease in non-small cell lung cancer to mean the presence of enlarged metastatic mediastinal nodes evident on plain chest roentgenograms or widening of the carina at bronchoscopy. Forty-one patients with non-small cell carcinoma of the lung and clinical N2 M0 disease presumed operable received 2 to 3 cycles of high-dose cisplatin with vindesine (or vinblastine sulfate) with or without mitomycin-C. Following chemotherapy, 30 patients (73%) had a major radiographic response. Of these patients, 28 had thoracotomy, and 21 (75%) of them had complete resection of the disease, 8 of whom had total sterilization of the tumor proven histologically. An additional 4 patients had limited microscopic foci of residual tumor either in lung or lymph nodes. Survival at 3 years from diagnosis was 34% for all patients, 40% for those who completed the combined treatment (chemotherapy and surgery), and 54% for those who had complete resection with a median follow-up of 44 months and a median survival not yet attained.

Adult↗
PubMed1987

Impact of early detection on the clinical course of lung cancer.

The Memorial Sloan-Kettering Lung Cancer Detection Program is described, and data from this study are reported and analyzed. The program enrolled 10,040 cigarette-smoking men who were screened for at least 5 years by annual chest radiographs; half the men randomly selected also had 4-monthly sputum cytologic examinations. Of the 354 lung cancers that developed in these men during the screening period and a 2-year post-screening period, nearly half were adenocarcinomas and nearly one third were epidermoid (or squamous) carcinomas. Lung cancers detected by screening were more likely to be early stage (53 per cent) and resectable (65 per cent) than were those discovered by other means (for example, symptoms) or in the post-screening period (20 per cent early stage, 32 per cent resectable). Sputum cytology was most effective in detecting squamous carcinomas early; chest radiographs were most effective for detecting adenocarcinoma. However, sputum cytology did not reduce lung cancer mortality among these men who were in a program of annual chest radiographic examinations. Overall 5-year survival for all of the men who developed lung cancer was 35 per cent, compared with the national average of 13 per cent.

Carcinoma↗
PubMed1986

Pulmonary Kaposi's sarcoma in the acquired immune deficiency syndrome. Clinical, radiographic, and pathologic manifestations.

Pulmonary Kaposi's sarcoma related to the acquired immune deficiency syndrome (AIDS) has not been well characterized. To define the clinical, radiographic, and pathologic features of this entity, 11 autopsy-proved cases of pulmonary Kaposi's sarcoma were reviewed. The most common clinical symptoms were dyspnea and cough, but hemoptysis and stridor were also found. Nodular infiltrates and pleural effusions were the most commonly found radiographic abnormalities. Pulmonary function tests were sensitive in detecting the pulmonary abnormalities due to Kaposi's sarcoma. A low diffusion capacity, lack of arterial desaturation with exercise, and obstruction to airflow were suggestive of pulmonary involvement with this malignancy. Although endobronchial Kaposi's sarcoma was visualized at bronchoscopy as cherry-red, slightly raised lesions, bronchial biopsy specimens always showed no abnormalities. Transbronchial brushings and biopsy specimens and analysis of pleural fluid were also not helpful in establishing a diagnosis. In the seven subjects with extensive parenchymal Kaposi's sarcoma at autopsy, the pleura was always involved. Eight subjects had involvement of the tracheobronchial tree. In all of the subjects, pulmonary Kaposi's sarcoma was a significant cause of morbidity, and in three of 11 subjects (27 percent) it was the direct cause of death.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Transthoracic aspiration cytology of pulmonary lesions.

In a seven-year period (1974 to 1981), 1,390 patients had transthoracic aspiration biopsy for radiologically suspected pulmonary neoplasms. Of the 1,209 proven malignant neoplasms, 1,059 (88%) were cytologically diagnosed as malignant. There were only two (0.2%) false-positive diagnoses both due to florid bronchoalveolar hyperplasia associated with granulomatous disease. Cytologic and histologic correlations for primary lung cancers were 92% for adenocarcinoma, 87% for oat cell (small cell) carcinoma, and 83% for epidermoid carcinoma. Characteristic cytomorphology of pulmonary carcinomas, some metastatic neoplasms, and inflammatory lesions are described.

Adenocarcinoma↗
PubMed1985

Severe bleeding from herpes esophagitis.

We describe a patient with the unusual complication of massive upper gastrointestinal bleeding secondary to herpetic esophagitis, whose bleeding persisted despite a vigorous antireflux regimen but who responded dramatically to intravenous acyclovir. The patient is reported to underscore the importance of considering herpetic infection of the esophagus as a cause of severe gastrointestinal bleeding so that appropriate therapy may be instituted.

Acyclovir↗