Bioavailability to rats of 14C-lindane residues in stored potato tubers

Potato tubers were applied with radiolabelled lindane (U-14C gamma- 1,2,3,4,5,6-hexachlorocyclohexane) at three dose levels 30, 150, and 300 ppm and stored for 30, 60 and 90 days at room temperature. The data revealed that lindane penetrated into the pulp tissues through the epidermal layer. The amounts recovered in the peel were found to increase with a greater storage period up to 60 days followed by a drop at 90 days. On the other hand, there was a slight increase in radioactivity in the pulp tissue from 30 to 60 days followed by significant increase after 90 days. The incorporation of the compound in the tubers was dose independent. Methanol extraction showed binding of about 8.1% and 5.8% of the applied dose in peel and pulp tissues, respectively. The insecticide was found to be bioavailable when rats health hazard. It is therefore, desirable to demonstrate that the quantity of the terminal residues may be safe for the consumer. In the present investigation an attempt was made to determine the fate and bioavailability of lindane when applied to stored potato tubers.

Ten years of experience with patients with chronic active liver disease variceal bleeding: ablative versus selective decompressive therapy

BACKGROUND

Variceal hemorrhage is an added major threat to survival in patients with chronic active liver disease (CALD). The hemodynamic consequences of surgical therapy and the continued activity of the underlying liver disease both contribute to the hepatic dysfunction and determine patient survival.

METHODS

Two hundred and seventy two consecutive cases of (Child A or B) variceal bleeding with chronic hepatitis were surgically treated during a 10-year period. Histologic chronic active hepatitis (CAH) was documented in 160 (59%) patients, whereas chronic persistent hepatitis (CPH) was evident in 112 (41%). The applied surgical procedure was distal splenorenal shunt (DSRS) in 99 (36%) patients, splenectomy and gastroesophageal devascularization (SGD) in 108 (40%), and splenectomy with left gastric ligation (SLGL) in 65 (24%) patients. The preoperative data base obtained on these patients was matched comparing the three surgical modalities within each pathologic group (p > 0.05).

RESULTS

The operative mortality was low among the patients with CAH (DSRS, 5.1%; SGD, 4.2%) with no deaths occurring in the CPH group. Among the individuals with CAH, recurrent variceal hemorrhage occurred significantly (p < 0.05) more often after SLGL (26%) and SGD (17%) than after DSRS (5%). Sclerotherapy rescued 93% (SGD) and 70% (SLGL) of the patients with rebleeding. DSRS significantly (p < 0.05) increased the risk of encephalopathy (28%) compared with SGD (4.2%) and SLGL (8%). The morbidity rates were quite low among the patients with CPH with no significant (p > 0.05) differences noted when the three surgical modalities were compared. Both groups experienced a significant (p < 0.05) increase in aspartate aminotransferase levels after the three procedures with a significant (p < 0.05) increase in bilirubin level occurring only after DSRS. The 5-year survival rate for the patients with variceal bleeding with CAH was 76% (DSRS), 73% (SGD), and 88% (SLGL). The leading causes of death were liver failure after DSRS (70%), variceal hemorrhage after SLGL (60%), and equally divided between septicemia (43%) and liver failure (43%) after SGD. The patients with CPH had a better 5-year survival of 89% (DSRS) and 100% (nonshunt operation).

CONCLUSIONS

These data showed that (1) CALD is common among cases of variceal bleeding; (2) elective surgical treatment of variceal hemorrhage in patients with Child A or B CALD has a low operative mortality; (3) SLGL backed up by sclerotherapy is a better surgical alternative to either selective shunt or SGD in patients with active hepatitis, and (4) both DSRS and nonshunt operation are equally good surgical options for patients with CPH.

Transseptal approach for mitral valve surgery. A safe alternative when the need calls

Within a 40-month period ending in June 1992, we used the transseptal approach in performing mitral valve surgery on 18 patients. The patients selected had 1 or more of the following indications: small left atrium; adhesions from previous cardiac surgery or rheumatic activity; large, organized left atrial thrombus: the need for concomitant tricuspid valve surgery; or any combination of these factors. We made the septal incision in the long axis of the fossa ovalis and extended it anteriorly and posteriorly, taking care not to injure either the aortic root or the coronary sinus. In 15 patients, we easily obtained good mitral exposure; in 3, exposure was still difficult. One patient died, but the cause of death was not related to the surgical approach. Although none of our patients had early postoperative cardiac arrhythmias, the small number in our series and the short follow-up time prevent us from predicting the effect of this incision on late postoperative cardiac arrhythmias. Therefore, we recommend limiting the transseptal approach to complex reoperations and to operations necessitating right atriotomy for concomitant procedures. It is also very useful in patients with a large, organized left atrial thrombus. Under these conditions, we conclude that using the transseptal approach for mitral valve surgery is a simple, safe, and time-saving technique.

Histopathological study of the bilharzial affection on the bladder and ureter

This study was carried out on 68 cases (50 bilharzial stricture lower ureter, eight vesico-ureteral reflux cases and ten control). In cases of reflux associated with bilharziasis heavy ova-deposition was obvious all through the ureteral wall especially per-ureteral sheath. Also heavy deposition in the bladder wall involved the detrusor and trigonal muscle with fibrosis and obliteration of Waldeyer's space and atrophy and fasciculation of detrusor and trigonal muscle. This implies ureteral rigidity, impaired mobility and compression against a firm detrusor buttress.

Detrusor morphology and pathology in relation to bladder outflow obstruction in bilharzial patients

The light and electron microscopic structure of detrusor muscle of trabeculated urinary bladder from patients with urodynamically proved bilharzial outflow obstruction had been compared with normal detrusor muscle. In bilharzial outflow obstruction, the detrusor muscle bundles were formed of relatively smaller smooth muscle cells widely separated by dense connective tissue, fatty infiltration, bilharzial ova, inflammatory cells and hyalinosis. No evidence of smooth muscle hyperplasia, mitosis, or fibroblastic proliferation. At the level of electron microscopy. The connective tissue infiltration was proved to be microfibriles apparently in continuity of the basal lamina of the smooth muscle. These pathological changes can explain both the morphological and urodynamic changes in bilharzial urinary bladder outflow obstruction.

Should both schistosomal and nonschistosomal variceal bleeders be disconnected?

Splenopancreatic disconnection (SPD) was conceived and implemented as a technical addition to distal splenorenal shunt (DSRS) to maintain its selectivity and preserve portal perfusion. The proposed hemodynamic and metabolic stability of hepatocytes after DSRS-SPD should improve survival. In this nonrandomized study, 145 consecutive (Child A/B) variceal bleeders were electively subjected to selective shunt with DSRS in 93 and DSRS-SPD in 52 patients. The 2 groups were similar before surgery with a mean follow up of 24 +/- 12 (DSRS) and 27 +/- 14 (DSRS-SPD) months. DSRS-SPD had an operative mortality of 3.8%. Postoperative pancreatitis occurred in 7.7% after DSRS-SPD and 3.2% after DSRS alone, with schistosomal hepatic fibrosis representing 86% of morbid cases. Shunt patency was high and recurrent variceal hemorrhage was low in both groups. Clinical encephalopathy was significantly reduced after DSRS-SPD (p less than 0.05). The addition of SPD significantly reduced both the incidence of chronic hyperbilirubinemia in the schistosomal patients (p less than 0.05) and the difference between the changes in total serum bilirubin in all patients (p = 0.001). Portal perfusion was preserved after DSRS-SPD in all of the angiographically-studied patients. The overall survival was 84% after DSRS and 88% after DSRS-SPD. The schistosomal patients showed an incidence of 95% and 96% survival after DSRS and DSRS-SPD, respectively. DSRS-SPD was able to improve survival (92%) better than DSRS (77%) among well-matched nonschistosomal patients. These data show: (1) DSRS-SPD still has low operative mortality and a high patency rate with a low incidence of recurrent variceal hemorrhage, (2) DSRS-SPD maintains portal perfusion, achieves better survival, and reduces the incidence of encephalopathy, especially in patients with nonalcoholic cirrhosis and mixed liver disease, (3) in the schistosomal population, DSRS-SPD reduces the incidence of chronic hyperbilirubinemia but increases the risk of postoperative pancreatitis.

Selective shunt versus nonshunt surgery for management of both schistosomal and nonschistosomal variceal bleeders

This clinical study included 219 (Child A/B) consecutive variceal bleeders. Electively 123 had distal splenorenal shunt (DSRS) and 96 had splenectomy with gastroesophageal devascularization (S&GD). Liver pathology was documented in 73% of patients, with schistosomal fibrosis in 41% and nonalcoholic cirrhosis or mixed pattern (fibrosis and cirrhosis) in 59%. The surgical groups were similar before operation, with a mean follow-up of 82 +/- 13 and 78 +/- 18 months, respectively (range, 60 to 120 months). The two pathologic populations were also similar before each and both procedures. The operative mortality rates were low, with incidences of 3.3% (DSRS) and 3.1% (S&GD). Rebleeding occurred significantly (p less than 0.05) more frequently after S&GD (27%) compared to DSRS (5.7%). Sclerotherapy salvaged 65% of S&GD rebleeders. Encephalopathy developed significantly (p less than 0.05) more after DSRS (18.7%) compared to S&GD (7.3%), with no significant difference among the current survivors. The difference in overall rebleeding and encephalopathy rates between both procedures was statistically related to patients with cirrhosis and mixed lesions (p less than 0.05). Distal splenorenal shunt significantly reduced the endoscopic variceal size more than S&GD (p less than 0.05). Prograde portal perfusion was documented in 94% of patients in each group, with a variable distinct pattern of portaprival collaterals in 91% (DSRS) and 65% (S&GD). The total population cumulative survival was similar with 80% for DSRS and 79% for S&GD (plus sclerosis in 23%), with hepatic cell failure the cause of death in 46% and 50%, respectively. However, in the schistosomal patients, survival was better improved after DSRS (90%) compared to S&GD (75%), with no difference among the cirrhotic and mixed group (DSRS 73%, S&GD 72%). In conclusion (1) both DSRS and S&GD have low operative mortality rates, (2) DSRS is superior to S&GD in the schistosomal patients, and (3) S&GD backed by endosclerosis for rebleeding is a good surgical alternative to selective shunt in the nonalcoholic cirrhotic and mixed population.

Schistosomiasis associated bladder carcinoma expression of cytokeratin

Twenty patients with bladder carcinoma (14 transitional cell carcinoma and six squamous cell carcinoma) and ten controls of (four with bilharzial lesions, three without and three with metaplasia and dysplasia) were subjected to immunocytochemical and immunohistochemical studies. Bladder and urine samples examination were carried out with the high molecular weight cytokeratin and broad spectrum keratin antibodies using peroxidase anti-peroxidase. Cytokeratins of high molecular weight were expressed in all squamous cancer while broad spectrum keratin was positive in 83.3%. The transitional cell carcinoma was positive in 50% with both cytokeratin and broad spectrum keratin. Urine shedded were positive in 83.3% and 66.7% of squamous cell carcinoma with high molecular weight cytokeratin and broad spectrum keratin respectively. However, each of them was positive in 50% of transitional carcinoma, and negative with non-malignant cases except with metaplasia and dysplasia.

Vascular changes in cutaneous leishmaniasis

Fifty cases of proven human cutaneous leishmaniasis were histopathologically studied. In twenty biopsies the picture was vascular alternations with or without fibrinoid necrosis and fibrin thrombi in both arteries and veins within the area of the inflammation in the lesions. Hyalinosis and intimal proliferation were also seen. On the other hand, immunoperoxidase staining of CL. lesions showed IgG and IgA within the endothelial cells, in the media and the perivascular space of the diseased vessels. It seems that the formation of immune complexes in the infected skin was responsible for the vascular changes.

The pattern of bilharzial infection with hepatitis B virus associated with delta agent

Delta hepatitis is a relatively common in Egypt especially in patients with chronic liver disease. Delta virus infection is associated with a high frequency of hepatic decompensation and it seems to impose additional burden on liver function. It does not seem to be more prevalent in particular type of cirrhosis but the CAH pathology was found to be mostly associated with virus infection. HBV replication seems to be inhibited by the presence of delta virus as evidenced by the low frequency of HBe Ag in serum and HBs Ag in liver among patients with HDV infection.

The relation of HLA-DR antigen, lymphocytes and natural killer cells in human bilharzial bladder carcinoma

The HLA-DR antigen type was studied in fifty-four patients with bilharzial bladder carcinoma and in ten patients but with non malignant bilharzial bladder lesions as controls. The monoclonal antibodies were used to identify the pattern of the distribution of lymphocytes subset and the natural killer cells. These immunohistochemical studies through some light on the relation between the different immunocompetent cells in the bladder tissue and suggested their functional role particularly in bilharziasis and in the tumour surveillance.

Schistosomal versus nonschistosomal variceal bleeders. Do they respond differently to selective shunt (DSRS)?

The distal splenorenal shunt (DSRS) was performed in 125 consecutive variceal bleeders. To date, no patients have been lost to follow-up (mean of 79 +/- 20 months). Liver pathology was documented in 85 patients: 45 patients had schistosomal hepatic fibrosis, 17 had nonalcoholic cirrhosis, and 23 had mixed pattern (hepatic fibrosis and cirrhosis). The preoperative data base for these three groups was matched (p greater than 0.05), with a mean follow-up of 79 +/- 20, 70 +/- 14, and 77 +/- 22 months for each population, respectively. The results showed low operative mortality (4.8%), high cumulative patency rate (94.8%) and low recurrent variceal hemorrhage (5.6%). The biochemical data showed significant increase in serum bilirubin (p less than 0.001) and aspartate transaminase (AST) (p less than 0.05) in the nonschistosomal patients. Chronic hyperbilirubinemia was found in 33% of the schistosomal group. Prograde portal perfusion was detected in 94% of the patients, with development of collaterals in 91%. The angiographic pattern of these collaterals was 50% pancreatic, 45% gastric, and 26% colosplenic. Patients with mixed liver disease had a high incidence of Grade III portal perfusion (57%) and more common pancreatic and gastric collaterals (71%). The cumulative survival for all patients was 74.1%, with hepatic cell failure being the leading cause of death (13 patients, 50% of all deaths). The schistosomal patients had a 91.6% incidence, whereas the cirrhotic and mixed groups had survival rates of 75.6% and 65.2%, respectively. Also, of a 15% total incidence of encephalopathy, 4.4% was related to the schistosomal patients, 23.5% to the cirrhotics, and 21.7% to the mixed population. Statistically, the survival rate was significantly better (p less than 0.05) and encephalopathy was significantly lower (p less than 0.05) in the schistosomal population. In conclusion, this data shows that: 1) DSRS has a high patency rate and a low variceal hemorrhage recurrence rate; 2) it maintains some degree of portal perfusion in patients with different nonalcoholic liver diseases, despite development of collaterals; and 3) the schistosomal patients have a better survival rate, with a low incidence of encephalopathy after DSRS, compared with the cirrhotic and mixed populations.

Distal splenorenal shunt for management of variceal bleeding in patients with schistosomal hepatic fibrosis

The distal splenorenal shunt was performed in 60 patients with schistosomal hepatic fibrosis in whom no evidence of cirrhosis was documented by preoperative needle and operative wedge biopsy. No patients have been lost to follow-up with a median of 37 months (range: 17-86). The results showed low operative mortality (1.7%), high patency rate (92.5%), and low recurrent variceal hemorrhage (6.7%). Thrombosed shunts were treated either by refashioning the shunt (1 patient) or splenectomy and gastric devascularization (2 patients). Initial hyperbilirubinemia and reduction in serum albumin were found in the early postoperative period, with persistent hyperbilirubinemia in 32% of the patients. The 5-year survival was 88%, with liver disease related mortality in only three patients. Clinical encephalopathy was detected in three patients (5.1%); only one of them was incapacitated. These data showed that: selective shunt (distal splenorenal shunt, DSRS) is an effective surgical procedure in the treatment of schistosomal variceal bleeding, shunt thrombosis is rare and can possible be corrected if detected early, schistosomal patients have a better survival and a lower incidence of encephalopathy after DSRS than that reported in cirrhotics, and liver biopsy should be performed for proper assessment of the schistosomal population especially in the geographic areas where the schistosoma parasite and viral hepatitis are endemic.

Behavior and viability of tobacco protoplasts in response to electrofusion parameters

This investigation examines responses of protoplasts in a systematic and quantitative way to the various electrical treatments used to achieve electrofusion and their individual and cumulative effect on protoplast viability. Mesophyll and cell suspension protoplasts from two species of the same genera, Nicotiana tabacum and N. rustica var brasilia were used in these experiments. Optimal frequencies for alignment of tobacco protoplasts were between 500 kilohertz and 2 megahertz at 100 volts per centimeter. Variations in frequency and voltage of the alternating current (AC) field caused predictable movements of protoplasts within an electrofusion chamber. AC frequencies below 10 hertz or above 5 megahertz significantly decreased the viability of protoplasts in the fusion chamber as estimated by fluorescein diacetate staining 1 hour after treatment. Although the direct current (DC) pulse appeared to have a slight detrimental effect on protoplast viability, this effect was not significantly different from untreated control preparations.Protoplasts from both leaf mesophyll cells and suspension cells were induced to fuse with one or more 10 to 30 microseconds DC square wave pulses of approximately 1 kilovolt per centimeter after the protoplasts had been closely appressed with an AC field.