Effect of a Vasopressin V2 Receptor Antagonist on Polycystic Kidney Disease Development in a Rat Model

BACKGROUND

Vasopressin V2 receptor inhibition is a clinically validated mechanism of action in the treatment of autosomal dominant polycystic kidney disease (ADPKD). In this study, the effect of lixivaptan, a potent, selective vasopressin V2 antagonist, was evaluated in PCK rats, a validated animal model of PKD.

METHODS

Four-week old PCK rats were fed rodent chow with 0.5% lixivaptan (low dose) or 1% lixivaptan (high dose), or chow only (control) for 8 weeks. Urine output was measured at weeks 7 and 10 of age. Animals were killed at 12 weeks of age; kidneys and livers were collected, weighted, and analyzed for cyclic adenosine 3',5'-monophosphate (cAMP) levels and cystic burden and fibrosis; serum creatinine and sodium were measured.

RESULTS

Consistent with the development of a polycystic kidney phenotype, control PCK rats showed enlarged kidneys, extensive cyst formation, and early signs of serum creatinine elevation at 12 weeks of age. Compared to controls, PCK rats treated with low-dose lixivaptan showed a 26% reduction in % kidney weight/body weight (p < 0.01); a 54% reduction in kidney cystic score (p < 0.001), a histomorphometric measure of cystic burden; a 23% reduction in kidney cAMP levels (p < 0.05), a biochemical marker of disease; and a 13% reduction in plasma creatinine (p < 0.001), indicating preserved renal function. These reductions were associated with 3-fold increases in 24-h urine output, demonstrating the potent aquaretic effect of lixivaptan. The fact that the high dose was less efficacious than the low dose is discussed.

CONCLUSIONS

These results provide the first evidence of the potential utility of lixivaptan for the treatment of ADPKD.

Nasoseptal cyst after septorhinoplasty: late and unusual but preventable compliation

Nasoseptal cyst after septorhinoplasty: late and unusual but preventable complication.

INTRODUCTION

Formation if a slowly growing cyst following septorhinoplasty is a rare but serious complication. Mucous cyst is more common than foreign body inclusion cyst. Typically, these cysts present as a solitary lesion that develops in the subcutaneous pace over the nasal bone along the line of nasal osteotomy several months or years after initial surgery. Rarely, the cyst onnects with the nasal septum. Surgery is the treatment of choice and consists of either complete excision of the cyst apsule or marsupialization of the cyst. ase report: A nasoseptal mucous cyst developed in a 46-year-old woman 10 years after septorhinoplasty. We successfully narsupialized the cyst with an endonasal endoscopic approach. onclusion:. Cysts can be removed by either complete resection of the cyst capsule or marsupialization via endonasal endoscopy. To prevent cyst formation, initial surgery must be conducted nontraumatically and tissue remnants cleared to prevent dispersion into subcutaneous spaces.

Interstitial laser photocoagulation (ILP) of benign cystic thyroid nodules--a prospective randomized trial

CONTEXT

Recurrence rate, after aspiration, in cystic thyroid nodules is very high. Interstitial laser photocoagulation (ILP) is a minimally invasive procedure that reduces the need for surgery in patients with a benign solid thyroid nodule.

OBJECTIVE

The aim of the study was to evaluate the efficacy of ILP on remission rates in recurrent, predominantly cystic thyroid nodules.

DESIGN AND METHODS

Forty-four consecutive outpatients with a symptomatic, recurrent, and cytologically benign cystic (cyst volume ≥ 2 mL) thyroid nodule were randomized to a single aspiration with (n = 22) or without (n = 22) subsequent ILP and followed up after 1, 3, and 6 months.

RESULTS

Successful outcome (cyst volume ≤ 1 mL) was obtained in 15 of 22 (68%) patients in the ILP group, compared to 4 of 22 (18%) in the aspiration group (P = .002). In the ILP group, the solid part of the nodule was reduced from a median of 1.8 to 1.0 mL (P = .02). In the aspiration-alone group, neither the cyst volume nor the solid nodule volume was significantly reduced. The reduction in median visual analog score (0-10 cm) for pressure symptoms was significantly higher in the ILP group (from 3.0 to 0.0 cm) than in the aspiration-alone group (from 4.0 to 3.5 cm) (P = .006, between groups). No major side effects occurred, and thyroid function was unaffected throughout.

CONCLUSIONS

US-guided aspiration and subsequent ILP of benign recurrent predominantly cystic thyroid nodules is safe. It significantly reduces recurrence rate, the volume of the solid nodule component, and pressure symptoms. ILP constitutes an important alternative to surgery in such patients.

Surgical management of common canine prostatic conditions

Prostatic diseases commonly warrant surgical intervention. Early castration may prevent the development of benign prostatic hyperplasia, prostatitis, and cavitary lesions (prostatic abscesses or cysts). In intact dogs that present with these disorders, castration should always be part of the specific surgical treatment because it enhances treatment success and may prevent recurrence. The current treatment of choice for cavitary lesions is prostatic omentalization, which results in lower postoperative mortality, faster recovery, and fewer incidences of recurrence than other prostatic drainage techniques. Prostatic neoplasia without evidence of metastasis may be managed with total prostatectomy, subtotal prostatectomy in conjunction with intraoperative radiotherapy, or postoperative chemotherapy. Understanding the neurovascular supply of the prostate and surrounding tissues is essential to decrease the risk for urinary incontinence, severe hemorrhage, and avascular necrosis. Postoperative management includes analgesia, appropriate antibiotic therapy, and in cases of subtotal or total prostatectomy, temporary urinary catheterization.

Inhibition of tubule-cell proliferation to prevent cyst formation: a new avenue to treat ADPKD?

Tubule-cell hyperproliferation precedes cyst development in autosomal dominant polycystic kidney disease (ADPKD). Parker et al. report that insulin-like growth factor-1 stimulates ADPKD cell proliferation by activating Ras and Raf; inhibition of Ras or Raf abolished this effect. Inhibiting tubule-cell proliferation could halt cyst formation and prolong survival of functional tubules, offering a new treatment for ADPKD patients.

VEGF receptor inhibition blocks liver cyst growth in pkd2(WS25/-) mice

Proliferation of cyst-lining epithelial cells is an integral part of autosomal dominant polycystic kidney disease (ADPKD) cyst growth. Cytokines and growth factors within cyst fluids are positioned to induce cyst growth. Vascular endothelial growth factor (VEGF) is a pleiotropic growth factor present in ADPKD liver cyst fluids (human 1,128 +/- 78, mouse 2,787 +/- 136 pg/ml) and, to a lesser extent, in ADPKD renal cyst fluids (human 294 +/- 41, mouse 191 +/- 90 pg/ml). Western blotting showed that receptors for VEGF (VEGFR1 and VEGFR2) were present in both normal mouse bile ducts and pkd2(WS25/-) liver cyst epithelial cells. Treatment of pkd2(WS25/-) liver cyst epithelial cells with VEGF (50-50,000 pg/ml) or liver cyst fluid induced a proliferative response. The effect on proliferation of liver cyst fluid was inhibited by SU-5416, a potent VEGF receptor inhibitor. Treatment of pkd2(WS25/-) mice between 4 and 8 mo of age with SU-5416 markedly reduced the cyst volume density of the liver (vehicle 9.9 +/- 4.3%, SU-5416 1.8 +/- 0.7% of liver). SU-5416 treatment between 4 and 12 mo of age markedly protected against increases in liver weight [pkd2(+/+) 4.8 +/- 0.2%, pkd2(WS25/-)-vehicle 10.8 +/- 1.9%, pkd2(WS25/-)-SU-5416 4.8 +/- 0.4% body wt]. The capacity of VEGF signaling to induce in vitro proliferation of pkd2(WS25/-) liver cyst epithelial cells and inhibition of in vivo VEGF signaling to retard liver cyst growth in pkd2(WS25/-) mice indicates that the VEGF signaling pathway is a potentially important therapeutic target in the treatment of ADPKD liver cyst disease.

Octreotide inhibits hepatic cystogenesis in a rodent model of polycystic liver disease by reducing cholangiocyte adenosine 3',5'-cyclic monophosphate

BACKGROUND AND AIMS

In polycystic liver diseases (PCLDs), increased cholangiocyte proliferation and fluid secretion are key features and cholangiocyte adenosine 3',5'-cyclic monophosphate (cAMP) is an important regulator of these processes. Thus, we assessed cAMP levels and evaluated octreotide (an analogue of somatostatin known to inhibit cAMP) in hepatic cyst growth using an in vitro model of cystogenesis and an in vivo animal model of autosomal recessive polycystic kidney disease (ARPKD), one of the PCLDs.

METHODS

Expression of somatostatin receptors (SSTRs) was assessed by reverse-transcription polymerase chain reaction and confocal microscopy in cholangiocytes from normal and polycystic kidney (PCK) rats, the ARPKD model of autosomal recessive polycystic kidney disease. Effects of octreotide on cAMP levels and cyst expansion were studied in vitro using PCK bile ducts grown in 3-dimensional culture. The effects of octreotide on hepatic and renal cystogenesis were investigated in PCK rats in vivo.

RESULTS

In cholangiocytes and serum of PCK rats, cAMP concentrations were approximately 2 times higher than in normal rats. SSTR subtypes that bind octreotide (ie, SSTR2, SSTR3, and SSTR5) were expressed in both normal and PCK cholangiocytes. In vitro, octreotide inhibited cAMP levels by 35% and reduced cyst growth by 44%. In vivo, octreotide lowered cAMP content in cholangiocytes and serum by 32%-39% and inhibited hepatic disease progression, leading to 22%-60% reductions in liver weight, cyst volume, hepatic fibrosis, and mitotic indices. Similar effects were observed in kidneys of PCK rats.

CONCLUSIONS

This preclinical study provides a strong rationale for assessing the potential value of octreotide in the treatment of PCLDs.

Thiamin deficiency: a possible major cause of some tumors? (review)

Based solely on clinical clues from a malnourished population, thiamin alone was intentionally and successfully injected to human cases with some tumors or masses. Two cases of submandibular gland cyst and 13 out of 15 cases of Baker's cyst were cured without recurrence for several decades. In a case with pathology-confirmed osteosarcoma, subcutaneous perfusion of thiamin HCl 300 once only reduced its circumference from 30 to 20 cm, equivalent to a reduction of 50-75% in volume, within 2 days. Current concepts on the role of thiamin in carcinogenesis are controversial. Some authors claimed that thiamin supported high rate of tumor cell survival, proliferation and chemotherapy resistance and suggested anti-thiamin therapy for cancer. On the other hand, some investigators have reported evidence of prevention of several varieties of cancers by dietary thiamin. A limited number of animal studies revealed evident relationship between thiamin deficiency and cancer development. Therefore, further study on the mechanism switching thiamin between cancer supporter and suppressor is needed.

Solar and photocatalytic disinfection of protozoan, fungal and bacterial microbes in drinking water

The ability of solar disinfection (SODIS) and solar photocatalytic (TiO(2)) disinfection (SPC-DIS) batch-process reactors to inactivate waterborne protozoan, fungal and bacterial microbes was evaluated. After 8 h simulated solar exposure (870 W/m(2) in the 300 nm-10 microm range, 200 W/m(2) in the 300-400 nm UV range), both SPC-DIS and SODIS achieved at least a 4 log unit reduction in viability against protozoa (the trophozoite stage of Acanthamoeba polyphaga), fungi (Candida albicans, Fusarium solani) and bacteria (Pseudomonas aeruginosa, Escherichia coli). A reduction of only 1.7 log units was recorded for spores of Bacillus subtilis. Both SODIS and SPC-DIS were ineffective against the cyst stage of A. polyphaga.

Clinical signs of hypoxia with high-Dk soft lens extended wear: is the cornea convinced?

PURPOSE

To assess the effectiveness of high-Dk soft contact lenses with oxygen transmissibility (Dk/L) beyond the critical level required to avoid corneal edema during overnight wear.

METHODS

The most up-to-date data available on clinical signs of hypoxia with high-Dk contact lenses is reviewed.

RESULTS

Chronic corneal edema associated with hypoxia is responsible for the development of large numbers of microcysts, limbal hyperemia, neovascularization, and small increases in myopia. Silicone hydrogel lenses worn continuously for up to 30 nights prevent corneal edema during overnight wear and do not induce a microcyst response. Long-term clinical trials indicate the mean level of limbal redness for patients wearing high-Dk lenses during continuous wear are equivalent to nonlens wearers. No changes in refractive error are associated with continuous wear of high-Dk lenses.

CONCLUSION

High-Dk silicone hydrogel lenses can be worn for up to 3 years with virtual elimination of the hypoxic consequences observed with low-Dk lenses made from conventional lens materials.

Long-term magnesium sulfate treatment as protection against hypoxic-ischemic brain injury in seven-day-old rats

OBJECTIVE

Our purpose was to study the effects of long-term treatment with magnesium sulfate on hypoxic-ischemic brain damage in newborn rats.

STUDY DESIGN

Seven-day-old rat pups (n = 120) were exposed to unilateral carotid artery ligation and 2 hours of hypoxia (8% oxygen in 92% nitrogen). Neuronal loss was evaluated in 4 groups. The loading dose group (n = 25) received a bolus injection of 270 mg/kg magnesium sulfate intraperitoneally. The maintenance group (n = 26) received 3 days of continuous infusion of magnesium sulfate with a micro-osmotic pump at a rate of 72 mg/kg per hour. The loading dose-plus-maintenance group (n = 23) received both. The control group (n = 46) did not receive magnesium. Seven days after the injury the pups were killed and the brains were removed for analysis. Severity of neuronal loss was evaluated in the cerebral cortex and hippocampus and compared among groups by chi2 test.

RESULTS

Cyst formation resulting from necrosis was significantly decreased in the maintenance group (15%) and loading dose-plus-maintenance group (9%) but not in the loading dose group (52%) relative to the control group (46%). Severity of neuronal loss in the cerebral cortex and the hippocampus was also significantly improved in the maintenance group and the loading dose-plus-maintenance group but not in the loading dose group. Mortality rates were not different among the groups. Magnesium ion concentrations at 24 hours were significantly decreased from the preinfusion value of 0.49 +/- 0.01 mmol/L in the control group (0.34 +/- 0.03 mmol/L) but remained within normal ranges in the maintenance group (0.46 +/- 0.02 mmol/L with a pump infusing 72 mg/kg per hour and 0.56 +/- 0.05 mmol/L with a pump infusing 24 mg/kg hour). There was an inverse relationship between the maintenance dose and neuronal loss but not between the maintenance dose and mortality rate.

CONCLUSION

Long-term magnesium administration had neuroprotective effects against hypoxia-ischemia in newborn rats.

Lymphedema and lymphocysts following lymphadenectomy may be prevented by omentoplasty: A pilot study

OBJECTIVES

Pelvic lymph node dissection as part of the staging surgery for cervical carcinoma interrupts the afferent lymphatics, so the lymph drains retroperitoneally. New surgical techniques designed to leave the peritoneum open after the retroperitoneal dissection, in particular the application of a pedicled omentoplasty along the dissection route, have been advocated to prevent the formation of lymphocysts and lymphedema. We investigated the possible benefit of pedicled omentoplasty in preventing lymphocysts and lymphedema following pelvic lymph node dissection.

METHODS

In this pilot study with historical controls we compared the formation of lymphocysts and lymphedema following two different surgical techniques for pelvic node dissection: group I (historical controls), in which the dorsal peritoneum was left open, and group II, in which the dorsal peritoneum was left open with application of a pedicled omentoplasty. In these two groups of gynecologic patients, we compared the lymph flow patterns and the occurrence of lymphedema following systemic pelvic lymphadenectomy. The two groups were of comparable clinical status and consisted of 12 (group I) and 10 (group II) patients. Lymphocysts, if any, were detected by CT scan, the lymph flow patterns were visualized by dynamic lymphscintography, and lymphedema was visualized by physical examination and magnetic resonance imaging of the groin and the upper leg.

RESULTS

In both groups a distinct intraperitoneal absorption of the lymph fluid was observed. Pedicled omentoplasty seemed to facilitate the absorption or transport of lymph fluid, resulting in less lymphedema in the upper leg.

CONCLUSION

It appeared that leaving the dorsal peritoneum open to give the lymph stream the opportunity to pour into the abdominal cavity is important in preventing lymphocysts and lymphedema. The dynamic lymphscintigraphy described in this paper showed that the intraabdominal lymph flow is absorbed by the peritoneum and even more quickly by the pedicled omentum.

Microsurgical repair of Stensen's duct using an interposition vein graft

Facial wounds are frequently associated with bone fractures and multiple trauma; however, disruption of the parotid gland or Stensen's duct is rare and is often associated with facial nerve palsy. Lesions are often undiagnosed on first assessment of the multiple trauma patient. If microsurgical repair of Stensen's duct provides good functional results, ignoring such lesions often leads to later complications such as fistulae and sialocoeles. Although simple ligation of Stensen's duct has been reported to give satisfactory results, the authors prefer a more anatomic reconstruction of this structure whenever possible. A case of Stensen's duct microsurgical repair using a vein graft are reported.

Regulation of neuroprotective action of vasoactive intestinal peptide in the murine developing brain by protein kinase C and mitogen-activated protein kinase cascades: in vivo and in vitro studies

Intracerebral administration of the excitotoxin ibotenate to newborn mice induces white matter lesions mimicking periventricular leukomalacia, the most frequent brain lesion occurring in premature human babies. In this model, coinjection of vasoactive intestinal peptide prevents white matter lesions. In the present study, coadministration of ibotenate, vasoactive intestinal peptide, and selective transduction inhibitors showed that protein kinase C and mitogen-associated protein kinase pathways were critical for neuroprotection. In vivo and in vitro immunocytochemistry revealed that vasoactive intestinal peptide activated protein kinase C in astrocytes and neurons, and mitogen-associated protein kinase in neurons. In vitro neuronal transduction activation was indirect and required medium conditioned by astrocytes in which protein kinase C had been activated by vasoactive intestinal peptide. Although vasoactive intestinal peptide did not prevent the initial in vivo appearance of white matter lesion, it promoted a secondary repair of this lesion with axonal regrowth. Through protein kinase C activation, vasoactive intestinal peptide also prevented ibotenate-induced white matter astrocyte death. These data support the following hypothetical model: Vasoactive intestinal peptide activates protein kinase C in astrocytes, which promotes astrocytic survival and release of soluble factors; these released factors activate neuronal mitogen-associated protein kinase and protein kinase C, which will permit axonal regrowth.

Seroma as a common donor site morbidity after harvesting the latissimus dorsi flap: observations on cause and prevention

This prospective study reveals that the incidence of seroma formation after harvesting the latissimus dorsi muscle by scalpel is reasonably moderate. This incidence is lower when the resulting skin flaps are tacked to the underlying structures with resorbable sutures. In contrast, electrocautery dissection shows a significantly much higher rate of seroma formation, probably because of thermal injury of the wide fascial wound layers or the subcutaneous fat tissue. Fifty-eight patients were distributed among three groups. Within each group a specific way of latissimus dorsi muscle harvesting and donor site treatment was accomplished. The group of scalpel dissection and skin flap fixation to the underlying layers with additional tacking sutures shows the lowest rate of seroma formation (9.1%, N = 2) due to the avoidance of shearing effects. A clearly higher incidence is present in the group of scalpel dissection without tacking sutures (38.1%, N = 8), whereas seromas most frequently result after electrocautery dissection without skin flap fixation (80.0%, N = 12).

Effect of magnesium sulfate on the development of cystic periventricular leukomalacia in preterm infants

To determine if magnesium sulfate has an effect on the development of cystic periventricular leukomalacia in preterm infants, this retrospective case control study was conducted. There were 23,382 infants born at three teaching hospitals in the metropolitan New York area from January 1992 to December 1994. Four hundred ninety-two infants met our entrance criteria. Criteria included a birth weight < 1750 g, survival to at least 7 days of life and at least one cranial ultrasound after 7 days of life. Infants exposed to magnesium sulfate in utero were less likely to develop periventricular leukomalacia. Two of 18 (11%) infants with periventricular leukomalacia were exposed to magnesium sulfate in-utero compared to 14 of 36 controls (39%) (p = 0.035) (OR = 0.196, 95% CI = 0.039-0.988). Pre-eclampsia as an independent factor was not associated with a reduced risk (p = 0.251) (OR = 0.294, 95% CI = 0.033-2.65). Preterm infants exposed to antenatal magnesium sulfate were found to have a reduced risk of developing cystic periventricular leukomalacia.

Principles of the surgical approach in human liver cystic echinococcosis

Ultrasonography (USG) has recently contributed much to the diagnostic of hepatic cystic echinococcosis (CE). The use of portable ultrasonograph allowed us to perform a community survey among 9482 people living in a high risk area for CE in the Florida Department (Uruguay). Positive USG results were found in 123 asymptomatic patients. 48 out of 51 USG positive cases were surgically confirmed and 3 were found to be false positive. The results of this survey allowed us to propose a new classification of the echographic imaging based on the parasite's various evolutive and involutive stages. The Echinococcus granulosus cyst size was compared with the parasite's evolutive stages. The cyst's segmentary topography and the related risk of CE is evaluated. The importance of cystic-biliary communication is pointed out and its rational surgical treatment described. Finally, an algorithm is presented facilitating the choice of a rational treatment.

The application of fibrin glue after axillary lymphadenectomy in the surgical treatment of human breast cancer

Experimental studies point out that a reduction of lymph flow can be obtained by the local application of fibrin glue following axillary lymphadenectomy in the surgical treatment of breast cancer. In a prospective study the influence of human fibrin glue on postoperative axillary lymph secretion and the period of drainage of the wound cavity were evaluated. In 40 patients, 5 ml of fibrin glue (Tissucol) was applied to the wound cavity by the use of a spray applicator (Tissumat) immediately after axillary dissection of the lymph nodes. For drainage of the wound area Redon suction-drains were used. The daily amount of postoperative lymph secretion was measured and drains were removed at a lymph secretion of less than 20 ml. 40 patients who underwent surgery and axillary lymphadenectomy without subsequent application of fibrin glue sourced as control group. No significant difference concerning the total amount of lymph secretion, the mean period of drainage or the incidence of lymphatic cysts was observed. In our study, the expected occlusion of the wound cavity by the application of fibrin glue after axillary lymphadenectomy did not lead to any advantage when compared with the control group.

Prenatal sonographic detection of isolated fetal choroid plexus cysts: should we screen for trisomy 18?

It has been established that the finding of a fetal choroid plexus cyst confers an increased risk of aneuploidy, predominantly trisomy 18. In view of this association many investigators have advocated amniocentesis when a choroid plexus cyst is identified by prenatal ultrasonography. A risk/benefit and economic analysis of such a policy is presented. When the following factors are taken into account-published data on the frequency of isolated choroid plexus cysts in second trimester fetuses, the risk of trisomy 18 in these fetuses, the population frequency of trisomy 18, the natural history and prognosis for these infants, and the risks and cost of amniocentesis--it is concluded that performing amniocentesis on second trimester fetuses with choroid plexus cysts is neither cost effective nor beneficial. For the detection of one infant with trisomy 18 that will survive past five months, 25 normal fetuses would be lost owing to amniocentesis. Identification of trisomy 18 by determining the presence of choroid plexus cysts in fetuses is not a worthwhile screening policy.

Treatment of encapsulated blebs with 30-gauge needling and injection of low-dose 5-fluorouracil

We describe a simplified needling procedure, performed at the slit-lamp, with injection of low-dose 5-fluorouracil to treat encapsulated filtering blebs. Between August 1989 and December 1990 we treated 17 eyes of 14 patients with this procedure. At 2 months 13 of the eyes had needed only one needling procedure. Risk factors for reencapsulation of the bleb were a history of three or more previous surgical procedures (p less than 0.05) and prolonged preoperative use of topical adrenergic drugs (p less than 0.05). At 1 year all but one eye had an intraocular pressure below 21 mm Hg (median 15 mm Hg). Twelve of the eyes had needed more than one needling procedure. There were no serious complications of the 32 procedures performed. The incidence rate of minor complications (wound leaks, corneal erosion and small hyphemas) was 38%.

[Prophylactic and therapeutic studies on intestinal giant-cystic disease of the Israel carp caused by Thelohanellus kitauei. II. Effects of physical and chemical factors on T. kitauei spores in vitro]

In a basic attempt to develop the prophylactic and therapeutic measures on intestinal giant-cystic disease of the Israel carp, Cyprinus carpio nudus, the effects of physical and chemical factors on viability or survival of the spores of Thelohanellus kitauei were checked in vitro by means of extrusion test on the polar filament. When the fresh spores suspended with 0.45% and 0.9% sodium chloride solution and distilled water were laid at 5 degrees C and 28 degrees C for short terms, the extrusion rates increased until the 3rd day, meanwhile when some of them were suspended with Tyrode's solution at -70 degrees C the rates increased gradually until the 8th day. Viabilities of the spores suspended with 0.9% saline and added antibiotics to the suspension at 5 degrees C for long terms lasted for 997 days and 1,256 days (presumed values) at maximum, respectively. The spores suspended with distilled water at 28 degrees C for long terms survived 152.4 days, but the spores suspended with Tyrode's solution at -70 degrees C for long terms showed almost the same viable pattern as early freezing stages up to 780 days. The spores suspended with Tyrode's solution, frozen at -70 degrees C and thawed at 5 degrees C, showed the highest rate of extrusion of the polar filament. In the case of frozen spores, the extrusion rates during heating tend to become higher in accordance with the increase of frozen period, and the critical points of 180 day-frozen spores to be killed were generally 78.5 hr. at 60 degrees C, 23.4 hr. at 70 degrees C, 189.1 min. at 80 degrees C or 10.5 min. at 90 degrees C. The longer the spores were frozen, the more time was needed for the death of spores after thawing; 20 days-17.4 days, 100 days-33.2 days, and 400 days-37.8 days. The longer the spores were frozen, the more time was needed for the death of spores at a conventional when they were dried air drying condition, 540 days-23.5 days, 160 days-21.0 days, and 20 days-14.4 days. On the other hand, the longer the spores were frozen, the more spores were dead rapidly when they were irradiated with 10W UV-ray; 100 days-26.0 hr, 300 days-21.9 hr, and 540 days-13.9 hr. The time needed for killing 200 days-frozen spores by various disinfectants at 1,000 ppm was 5.2 min. by calcium oxide, 10.4 min. by potassium permanganate, 27.8 min. by malachite green and 14.3 hr. by formalin.(ABSTRACT TRUNCATED AT 400 WORDS)

[Prophylactic and therapeutic studies on intestinal giant-cystic disease of the Israel carp caused by Thelohanellus kitauei. I. Course of formation and vanishment of the cyst]

In an attempt to develop prophylactic and therapeutic measures of the intestinal giant-cystic disease caused by Thelohanellus kitauei in the Israel carp, Cyprinus carpio nudus, pathological observations were conducted upon the carps which were hatched in May 1988 and raised in a net cage fish farm at the Soyang lake, managed by Horim Fisheries for the period of 21 months with 1-2 months interval. After a gross inspection of the carps, necropsy was carried out periodically in order to clarify the pathological changes in various internal organs and muscular tissues. Also, the prevalence of the disease was checked during the period from 1988 to 1990. Gross inspections revealed that the infected carps showed some degree of fading in body and gill color, back-emaciation symptoms, reddish anus accompanying erosion and relaxation and pot-belly, as well as discharge of yellowish white mucoid material from the anus. However, most carps died eventually of intestinal obstruction. Other significant necropsy findings included cyst formation of various size in the intestinal mucosa, ascites, anemic condition through internal organs and muscular tissues, hyperemia and dilation of intestines with decreased tension, thinness and fragility, and full contents of semi-fluid or yellowish white mucoid material in the intestinal canals. Based on the morphological characteristics of the spores found in the cysts, parasitic location in the intestines, macro- and microscopic findings of the lesions, the parasites were identified as Thelohanellus kitauei Egusa et Nakajima, 1981. Although monthly changes of water temperature were distinct, the extrusion rates of the polar filaments of the spores stayed constant throughout the year with an exception of a lower rate in July. The lesions initiated from mucosa and submucosa in early July became large swellings and then complete mature forms following the peracute course. From late August the upper cysts were gradually opened and most of the spores were dispersed from anus into the surrounding water through December but only a few lasted until next April. The cysts were completely recovered until next September. Comparing the incidence and prevalence of the disease by year tremendous infection and death rates were checked in the first prevalent year, 1988, but the rates were significantly decreased in the second year, and showed an almost normal status in the third year, 1990. As the above summarized results showed, the disease entity might come to an end in three years after the first prevalent year, however, the spores must be strictly prevented because they could be infective in the water for one year.

[Prevention of postoperative lymphocele after breast amputation]

Closed suction drainage is widely used after modified radical mastectomy to prevent accumulation of serum or lymph and to promote adherence of the skin flaps to the chest wall. However, between 5 and 35% of the patients develop seroma, which may prolong their stay in hospital and require more frequent post-operative outpatient visits. The prospective study reported demonstrate a significant correlation between the incidence of post-operative seromas, the duration of suction drainage and the amounts of fluid drained. The incidence of seroma also correlated significantly with the patient's age, the size of the breast removed, the presence of arterial hypertension and the post-operative use of heparin. Pre-operative radiotherapy and the TNM type of the tumour had no effect on the duration and volume of drainage nor on the occurrence of seromas. A drainage of short duration and a short stay in hospital are advocated for most mastectomy patients. Delayed mobilization of the shoulder should decrease the volume of accumulated fluid and the incidence of seromas.

The mechanism of spinal cord cavitation following spinal cord transection. Part 3: Delayed grafting with and without spinal cord retransection

Cavitation adjacent to transection of spinal cords can be successfully eliminated by a second operation 1 week after the initial spinal cord transection. The second operation consists of removal of the necrotic spinal cord tissue, thus producing a gap. Segments of autogenous sciatic nerve are inserted into the gap between the spinal cord stumps. If the spinal cord is injured by retransection at the second operation, cavitation again occurs in the spinal cord stumps resulting in separation of the nerve grafts from the spinal cord. The results of the present experiments support the concept that lysosomal spinal cord autotomy, which causes spinal cord cavitation, is a self-limiting process and that once the spinal cord has completed the autotomy, the process will not occur again unless the spinal cord is agiain traumatized.

[Spinal cord tumor in childhood--case report on an extradural cyst in the spinal cord]

The present paper is concerned with special aspects of the incidence, type-specificity, age distribution, and symptomatology of spinal tumors in childhood. Differences from similar processes observed in adults agre discussed. Difficulties of diagnosis are reported, and the advantages and disadvantages of various diagnostic methods are described. The case of an eleven-year-old child who was diagnosed as having developed an extradural spinal cyst has been restored to for a discussion of this rare phenomenon. The usually unfavorable prognosis in the case of childhood spinal tumors underscores the need for early recognition and immediate surgical therapy.

[Lymph flow disorders following arterial surgery of the leg]

In a series of 342 arterial reconstructions of the iliacolic to popliteal arteries 24 patients with lymph vessel damage were observed. The diagnosis of lymphedema was established in 18 patients by clinical findings and in 2 of them the diagnosis was confirmed by lymphography with followup of 1 year. Three patients developed an internal lymphogenic cyst, 3 showed an external lymph fistula, and 1 patient developed an infection of a dacron bifurcation graft. The infection occurred when an additional occlusion of the left femoral artery was bypassed with an autologous saphenous vein graft and a lymph cyst in the groin, which was excised several times, became infected. The patient was treated successfully by excising the graft and performing an axillofemoral bypass. Although cases of surgical damage to lymph vessels following arterial reconstructions are rare in the literature, it is assumed that this complication occurs more often than reported, because of lack of lymphographic information.