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K R Reddy

Publications and source records attributed to K R Reddy.

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

Benign and solid tumors of the liver: relationship to sex, age, size of tumors, and outcome.

From 1983 through 1997, our center diagnosed 130 cases of benign neoplasms: 27 with focal nodular hyperplasia (FNH), 25 with hepatic adenoma, 71 with cavernous hemangioma, and seven with mixed tumors of different diagnoses. Most often these lesions were seen in females [female-to-male ratio (f/m): 5.5/1]. Hepatic adenomas and mixed tumors were seen exclusively in females and FNH predominantly in females (f/m: 26/1). Hemangiomas, however, were not uncommon in men (f/m: 52/19) relative to the other tumors (P < 0.001). Furthermore patients with hemangioma were older (mean age: 49 years) whereas patients with hepatic adenoma, FNH, and mixed tumors were often younger (mean age: 33, 35, and 44 years respectively; P < 0.004). Oral contraceptive steroid use was related by 21 of 25 patients (84%) with hepatic adenoma, 22 of 26 (85%) females with FNH, five of seven (71%) females with mixed tumors, and 10 of 52 (19%) patients with hemangioma. Ninety-five of the 130 patients (73%) had one or more symptoms. There was no statistically significant correlation between symptoms and the size of the lesion, the final diagnosis, and whether there were solitary or multiple masses. Three of 25 (12%) with hepatic adenoma presented with rupture, and one of 27 (4%) with FNH had such a consequence. None of the hemangiomas presented with rupture or progressed to such a state. One patient with hepatic adenoma (4%) had a focus of malignancy. Surgical removal of benign tumors was performed in 82 of 130 patients (63%), and there was one operative mortality (1.2%) in a patient who had a caudate lobe FNH. The types of surgical procedures included segmentectomy (62%), lobectomy (34%), and trisegmentectomy (4%). In two of 84 patients who had undergone laparotomy resection was not technically possible. Resection is recommended in all cases of hepatic adenoma because of fear of rupture or associated focus of malignancy. FNH was not observed to undergo a malignant transformation and will rarely rupture. Surgery is only recommended for symptomatic hemangioma, and size of the lesion is not a criterion for excision.

Adenoma, Liver Cell↗
PubMed2001

The use of macrophyte-based systems for phosphorus removal: an overview of 25 years of research and operational results in Florida.

Phosphorus (P) removal from wastewaters and surface runoff using macrophyte-based systems (MBS) has been a topic of great interest in Florida for over 25 years. During this period, P removal by both treatment wetlands and floating aquatic macrophyte systems has been evaluated from both a research and operational standpoint. Several factors have contributed to the increased focus on the use of MBS for P removal. First, there exist no conventional technologies that can cost-effectively achieve the low outflow P concentrations required to protect the integrity of Florida's relatively pristine surface waters. Second, because MBSs typically provide some water storage, they can accommodate the wide ranges of flows typical for runoff sources such as agricultural drainage waters. Finally, many regions in Florida have sufficient area for deployment of the relatively land-intensive MBS technologies. The first P removal work in Florida was initiated in the mid-1970s, and involved pilot-scale research on domestic wastewater treatment by natural wetlands. Parallel studies were performed with managed (periodically harvested) floating plant systems (i.e., Eichhornia crassipes) for tertiary treatment. Since that time, the range of operational systems that have been deployed include emergent macrophyte-based and forested wetlands, managed floating plant systems, and submerged macrophyte-based systems. Waters treated by MBS include domestic effluents, agricultural runoff and eutrophic lake waters. Phosphorus removal targets for MBS in Florida have been as low as 10 microg/L. In this paper, we summarize research and operational results for MBS in Florida over the past 25 years.

Biodegradation, Environmental↗
PubMed2000

Effect of groundwater flow on remediation of dissolved-phase VOC contamination using air sparging.

This paper presents two-dimensional laboratory experiments performed to study how groundwater flow may affect the injected air zone of influence and remedial performance, and how injected air may alter subsurface groundwater flow and contaminant migration during in situ air sparging. Tests were performed by subjecting uniform sand profiles contaminated with dissolved-phase benzene to a hydraulic gradient and two different air flow rates. The results of the tests were compared to a test subjected to a similar air flow rate but a static groundwater condition. The test results revealed that the size and shape of the zone of influence were negligibly affected by groundwater flow, and as a result, similar rates of contaminant removal were realized within the zone of influence with and without groundwater flow. The air flow, however, reduced the hydraulic conductivity within the zone of influence, reducing groundwater flow and subsequent downgradient contaminant migration. The use of a higher air flow rate further reduced the hydraulic conductivity and decreased groundwater flow and contaminant migration. Overall, this study demonstrated that air sparging may be effectively implemented to intercept and treat a migrating contaminant plume.

Air↗
PubMed2000

Cholangiocarcinoma in patients with primary sclerosing cholangitis: a multicenter case-control study.

Patients with primary sclerosing cholangitis (PSC) have a significantly increased risk of developing cholangiocarcinoma (CCA). Risk factors for developing such a complication are not well defined. We conducted a multicenter, case-control study to determine the risk factors and possible predictors for CCA in patients with PSC. The demographic, clinical, and laboratory features of 26 PSC patients with CCA diagnosed over a 7-year period at eight academic centers were compared with 87 patients with PSC but no CCA (controls). There was no statistically significant difference in demographics, smoking, signs or symptoms or complications of PSC, indices of disease severity (Mayo Risk score or Child-Pugh score), frequency or duration or complications of inflammatory bowel disease (IBD), frequency of biliary surgery, or therapeutic endoscopy between the two groups. Alcohol consumption was significantly associated with CCA in patients with PSC (odds ratio: 2.95; 95% CI: 1.04-8.3). Serum carbohydrate antigen 19-9 (CA 19-9) was significantly higher in patients with CCA than those without (177 +/- 89 and 61 +/- 58 U/mL, respectively; P =.002). A serum CA 19-9 level > 100 U/mL had 75% sensitivity and 80% specificity in identifying PSC patients with CCA. In conclusion, alcohol consumption was a risk factor for having CCA in PSC patients. The indices of severity of liver disease were not associated with CCA in patients with PSC. Serum CA 19-9 appeared to have good ability to discriminate PSC patients with and without CCA.

Alcohol Drinking↗
PubMed2000

A multicenter, randomized trial of daily high-dose interferon-alfa 2b for the treatment of chronic hepatitis c: pretreatment stratification by viral burden and genotype.

OBJECTIVES: The aim of this study was to determine prospectively whether an intensive regimen of daily, high-dose interferon would improve the response rate for the treatment of chronic hepatitis C in patients with unfavorable virological characteristics. METHODS: A total of 104 patients with chronic hepatitis C were randomized at eight centers to receive interferon alfa-2b at a dose of 5 million units (MU) daily or 3 MU t.i.w. for a period of 24 wk. Patients were prospectively randomized by low or high viral burden and stratified by genotype. HCV RNA was measured by quantitative polymerase chain reaction, and response rates were compared between the dosage regimens. RESULTS: HCV RNA levels dropped more rapidly to lower levels in the group treated with 5 MU daily. In this group, the initial virological response (IR) at wk 12 and the end-of-treatment response (ETR) at wk 24 were double that of patients treated with standard interferon (66% vs 33% and 48% vs 24%, p < 0.01). Sustained response rates were low for both dose groups (14% vs 4%, p = 0.08). Genotype-related differences in initial response rates were present in the standard dose group (63% non-1 genotype vs 24% genotype 1; p = 0.005) but not in those treated with 5 MU daily (66% vs 67%, p = NS). Using multivariate analysis, only the interferon dose was associated with IR and ETR (p = 0.002). CONCLUSIONS: Daily, high dose interferon rapidly dropped HCV RNA and increased initial and end-of-treatment response rates when compared to t.i.w. regimens. This effect, independent of viral burden and genotype, suggests that patients with unfavorable viral characteristics might benefit from an intensive regimen that promotes rapid viral clearance. These data support further study of the use of high-dose induction regimens. However, improvements in sustained response rates will require additional therapeutic maneuvers such as prolonged therapy or the adjunctive use of ribavirin.

Adult↗
PubMed1999

Randomized, placebo-controlled, double-blind, multicenter trial of efficacy and safety of granulocyte colony-stimulating factor in liver transplant recipients.

BACKGROUND: Infection and rejection are two common complications after liver transplants. In a preliminary study, administration of granulocyte colony-stimulating factor (G-CSF) to liver transplant recipients was associated with a decrease in sepsis episodes, sepsis-related deaths, and rejection compared with a historical control group of patients. The purpose of this study was to evaluate further the efficacy of G-CSF in liver transplant patients in a randomized, placebo-controlled, double-blind, multicenter trial. METHODS: Adult patients with a United Network Organ Sharing classification of 1 or 2 were randomized to receive a placebo, 100 microg/day of G-CSF or 300 microg/day of G-CSF. The study drug was started preoperatively and then continued after the transplant for a maximum of 21 days. Patients were evaluated for microbiologically-documented infection, biopsy-proven rejection, number of treatments for rejection, length of stay in the intensive care unit and hospital, graft survival, death, and adverse events. RESULTS: During the first 30 days after the transplant, the median peak white blood cell count was 16.5x10(9)/L, 34.6x10(9)L, and 54.8x10(9)/L for the placebo, low-dose G-CSF, and high-dose G-CSF patients, respectively. The incidence of infection was 30% in G-CSF patients (34 of 114 patients) and 34% in placebo patients (20 of 58 patients). Except for more nosocomial pneumonias in the G-CSF patients (7 in 114 patients vs. 0 in 58 patients, P=0.056), the types of infections and causative organisms were also similar in both treatment groups. Although the number of treatments for clinically suspected or proven rejection was similar in the G-CSF and placebo patients, biopsy-proven rejection occurred more often in G-CSF patients (34 of 114 patients or 30%) than placebo patients (11 of 58 patients or 19%) (P=0.093). There were no cases of graft loss caused by rejection. G-CSF had no effect on length of stay in the intensive-care unit or hospital. There were 22 G-CSF patients (18%) and 10 placebo patients (15%) who died within 120 days after the transplant. No serious adverse events were attributed to G-CSF. CONCLUSION: Despite producing substantial increases in the white blood cell count after the transplant, G-CSF had no beneficial effects on infection, rejection, or survival in this study. Biopsy-proven rejection and nosocomial pneumonias were more common in patients treated with G-CSF compared with those taking the placebo. No serious adverse events were attributed to G-CSF.

Adolescent↗
PubMed1999

Racial differences in responses to therapy with interferon in chronic hepatitis C. Consensus Interferon Study Group.

The likelihood of a sustained response to a course of interferon in patients with chronic hepatitis C correlates with several clinical and viral factors, including age, viral genotype and initial levels of hepatitis C virus (HCV) RNA in serum. The role of race and ethnicity has not been assessed. We evaluated the association of race with response to interferon in a large randomized, controlled trial using either consensus interferon (9 microg) or interferon alfa-2b (3 million units) given three times weekly for 24 weeks. African-American patients participating in the study were similar to white patients in mean age (43 vs. 42 years) and baseline levels of HCV RNA (3.6 vs. 3.0 million copies/mL) but had lower rates of cirrhosis (5% vs. 12%) and more frequently had viral genotype 1 (88% vs. 66%: P =.004). Most strikingly, the rates of end-of-treatment and sustained virological responses were lower among the 40 African-American patients (5% and 2%) than among the 380 white patients (33% and 12%) (P =.04 and.07). Rates of response among Hispanic and Asian-American patients were not statistically different than non-Hispanic white patients. Median viral levels decreased by week 24 of therapy by 2.5 logs in white patients (from 3.0 to 0.012 million copies/mL) but by only 0.5 logs among African- American patients (from 3.6 to 1.8 million copies/mL). Thus, there are marked racial differences in virological responses to interferon in hepatitis C that must be considered in assessing trials of interferon therapy and in counseling patients regarding treatment. The differences in response rates are as yet unexplained.

Adolescent↗
PubMed1999

Experience with staging laparoscopy in pancreatic malignancy.

BACKGROUND: The role of diagnostic laparoscopy in the staging of abdominal malignancies is not well defined. METHODS: We retrospectively reviewed the usefulness of diagnostic laparoscopy as a staging procedure in pancreatic malignancy. This experience between February 1988 and May 1997 involves 109 cases of suspected or proven pancreatic malignancy. All laparoscopies were performed with the patient under conscious sedation and local anesthesia in an endoscopy suite. RESULTS: Of the 109 patients with pancreatic cancer, 45 (42%) had metastatic disease. The use of computed tomography (CT) alone revealed the existence of liver metastases in 10 of 109 (9%) patients, which were confirmed laparoscopically. The further use of laparoscopy identified metastases in 29 more cases: hepatic, 23; hepatic and peritoneal, 3; peritoneal and mesenteric, 1; and mesenteric, 2. CT in conjunction with laparoscopy therefore revealed metastatic liver, peritoneal, or mesenteric lesions in 39 of 109 (36%) patients with pancreatic cancer. After staging laparoscopy, 67 of 69 patients underwent laparotomy. Metastatic disease was identified at laparotomy in 6 more patients; however, only 4 of these patients had metastases to the liver whereas 2 had metastases to the peripancreatic lymph nodes. Therefore, in patients with pancreatic malignancy, the negative predictive value for the diagnosis of metastases to the liver, peritoneum or mesentery was 94% (61 of 65 patients). The positive predictive value of laparoscopy alone for the detection of metastatic disease to the liver, peritoneum, or mesentery was 88% (29 of 33 patients). Laparoscopy was successfully performed without complications in all patients with pancreatic cancer; however, one had a technically unsatisfactory examination. The overall rate of resectability after staging by imaging studies and laparoscopy was 57% (35 of 61 patients). CONCLUSIONS: In patients with a negative CT for metastases, laparoscopic identification of metastases avoided unnecessary laparotomy in 29 of 99 (29%) patients with pancreatic cancer. Staging laparoscopy is indicated in all cases of pancreatic malignancy before an attempt at a surgical cure.

Aged↗
PubMed1999

Postoperative jaundice.

Postoperative jaundice is often multifactorial (Fig. 2). A precipitating or causative factor may be identified but seldom can a specific therapy be offered. A systematic approach will help eliminate a hepatotoxic drug or identify a biliary tract problem. Treatment involves discontinuation of an offending drug; however, the drug, such as an anesthetic agent, may not be in use when the jaundice is detected. Recognition of an anesthetic-induced injury would certainly warn the physician not to repeat its use in future surgery for that patient. Hyperalimentation may contribute to jaundice, but patients developing postoperative jaundice are generally very ill and require nutrition. Extrahepatic biliary tract disease should be readily recognized and treated. The physician should be alert to the possibility of acalculous cholecystitis so that it can be appropriately diagnosed and treated.

Anesthetics↗
PubMed1999

Persistence of hepatitis C virus in a human megakaryoblastic leukaemia cell line.

Thrombocytopenia is a frequent clinical finding in patients with hepatitis C virus (HCV) infection. Platelets from patients with HCV infection have been identified as carriers of HCV RNA in our previous studies. The present study was designed to further investigate the possibility of HCV replication in megakaryoblasts from which platelets are eventually released. A megakaryoblastic cell line (MEG-01), established from a chronic myelogenous leukaemia patient 13 years ago, was used for this study. The MEG-01 cells were inoculated with fresh serum from a patient with HCV infection and renamed MEG-01-I cells. Surprisingly, both MEG-01 and MEG-01-I were positive by HCV reverse transcription-polymerase chain reaction (RT-PCR) for the existence of HCV RNA and minus-strand HCV RNA, regardless of inoculation. This was further confirmed by in situ RT-PCR. The HCV antigens, such as core, envelope, and non-structural (NS)3 and NS4, were also present in both cell lines, as identified by Western blotting and indirect immunofluorescence staining. In addition, virus-like particles were observed by electron microscopy in the MEG-01 cell line as well as in the MEG-01-I cell line. These findings indicate that the megakaryoblasts are vulnerable to HCV infection and that replication of HCV can occur in these cells. This may help us to better understand the pathogenesis of thrombocytopenia in patients with HCV infection. The MEG-01 cell line, which may have been continuously shedding HCV for years, should be a useful model for experimental research into HCV.

Fluorescent Antibody Technique↗
PubMed1999

Diagnostic laparoscopy: an update.

With new technical advances, wider availability, and the recent proliferation of less invasive surgery, the use of diagnostic laparoscopy has expanded far beyond its traditional role in the evaluation of chronic liver disease. Short of open laparotomy, diagnostic laparoscopy is the most accurate modality for staging of intra-abdominal malignancies, and is particularly well-suited for patients who otherwise would not require surgical palliation. In addition to avoiding unnecessary laparotomy in this group, diagnostic laparoscopy has proved valuable in the assessment of abdominal trauma, acute abdomen, and ischemic bowel disease. We briefly review here some of the new developments in the field of diagnostic laparoscopy.

Abdomen, Acute↗
PubMed1999

A phase I study of chemoembolization with cisplatin, thiotepa, and lipiodol for primary and metastatic liver cancer.

Thirty patients with primary hepatocellular carcinoma or liver metastases were entered into a program of chemoembolization with cisplatin, lipiodol, and escalating doses of thiotepa. Doses of cisplatin were 100/m2, and thiotepa doses ranged from 9 mg/m2 to 24 mg/m2. Two of three patients with ocular melanoma had partial responses in the liver metastases for 3+ and 16 months. In patients with either hepatocellular carcinoma (15 patients) or primary cholangiocarcinoma of the liver (three patients), there were two partial responses, for 22 and 33 months. Five patients had minor responses: four with a 40% reduction in tumor and one with a mixed response. There were four early deaths, which involved sepsis in two patients, respiratory failure in one, and acute myocardial infarction in one. Otherwise, toxicity was tolerable and reversible and included abdominal pain and transient elevation of serum creatinine, bilirubin, and transaminases. Less common toxicities included ototoxicity and peripheral neuropathy. Chemoembolization of the liver with cisplatin, thiotepa, and lipiodol can produce responses, but toxicity can be significant. The recommended starting phase II dose for future studies is thiotepa 24 mg/m2 and cisplatin 100 mg/m2.

Adult↗
PubMed1998

In situ enzymatic oligonucleotide amplification of hepatitis C virus-RNA in liver biopsy specimens (reverse transcriptase in situ polymerase chain reaction) after orthotopic liver transplantation for hepatitis C-related liver disease.

BACKGROUND: Hepatitis C infection recurs after orthotopic liver transplantation for hepatitis C virus (HCV)-related end-stage liver disease. Overlapping histopathologic features may present difficulties in differentiating recurrent HCV in the allograft from other conditions, especially rejection. METHODS: In this study, we evaluated the presence of HCV-RNA by reverse transcriptase in situ polymerase chain reaction (RT in situ RCR) in hepatic tissue, after orthotopic liver transplantation for HCV-related liver disease. Further, detection of HCV-RNA was correlated with the serum HCV-RNA levels, histopathology, and clinical outcome. RESULTS: Twenty-five patients were part of this study. Seventeen patients were transplanted for HCV cirrhosis and eight for an underlying disease other than HCV. None of the patients in the non-HCV group had in situ RT-PCR detection of HCV-RNA. Positive RT in situ PCR for HCV was found in 9 of 17 HCV patients, and the patients had a clinical course consistent with recurrent hepatitis C disease. Four of these nine patients had an initial histologic diagnosis of rejection. The other eight patients in the HCV group had negative RT in situ PCR, and none of them had a course compatible with recurrent HCV disease, although four patients were histologically diagnosed as having chronic C hepatitis. The mean HCV-RNA level (log/mL) in the patients who had in situ detection of HCV-RNA was 7.01+/-0.26. Although RT-PCR was negative in 8 of 17 HCV patients, the patients were serologically viremic and the mean HCV-RNA level was 6.05+/-0.33 (P=0.03). CONCLUSIONS: Our findings indicate that the HCV in situ RT-PCR assay may be helpful in the differentiation of recurrent hepatitis C disease from rejection. This may further help in the adjustment of immunosuppression.

Adult↗
PubMed1998

Comparison of tacrolimus with microemulsion cyclosporine as primary immunosuppression in hepatitis C patients after liver transplantation.

BACKGROUND: Immunosuppression in patients with hepatitis C virus (HCV) following orthotopic liver transplantation can lead to significant increases in serum viral loads. Our aim was to analyze the effect of a randomized study of two immunosuppressive agents (tacrolimus vs. microemulsion cyclosporine) on the outcome of HCV patients following orthotopic liver transplantation. METHODS: From December 1995 to September 1996, 50 adult patients transplanted for HCV cirrhosis were randomly assigned to receive tacrolimus (Prograf) (group 1, 25 patients) or microemulsion cyclosporine (Neoral) (group 2, 24 patients). All patients received alpha-interferon after transplantation, and the overall steroid doses were no different between the groups. Serum RNA levels were measured by signal amplification of Chiron. Biopsies were taken when transaminases were greater than 2x base line or when there was an inappropriate response to alterations in immunosuppression regimens. RESULTS: There were more episodes of rejection in the Neoral group, but there were no differences in bacterial and viral infections, nor in the rate of HCV recurrence between the two groups. There were seven deaths in group 1 and eight in group 2. Overall patient and graft survival rates in the Prograf and Neoral groups at 18 months were 72 and 68% and 67 and 64%, respectively. CONCLUSIONS: (a) Both immunosuppression regimens had similar HCV recurrence rates; (b) there were no differences in bacterial or opportunistic infections; and (c) patient and graft survival was similar between the two groups.

Adult↗