Clinical findings, surgical treatment and outcome in dogs with parotid duct ectasia: 14 cases (2010-2023).

OBJECTIVES: To describe the clinical presentation, diagnostic findings, surgical treatment and outcome of dogs diagnosed with parotid duct ectasia. MATERIALS AND METHODS: Medical records of dogs diagnosed with parotid duct ectasia between 2010 and 2023 at six small animal referral hospitals were retrospectively reviewed. Outcome was assessed by contacting the owners or referring veterinarians. RESULTS: Fourteen dogs were included. Lateral facial swelling was the most common clinical presentation. CT revealed a tortuous cavitary tubular fluid-filled structure consistent with a dilated parotid duct in all dogs. Surgical treatment included marsupialisation of the parotid duct papilla, surgical exploration of the duct alone, parotid duct marsupialisation with surgical exploration of the duct, parotidectomy or en-bloc parotid duct resection. The aetiology of parotid duct ectasia was not established in 13 of 14 dogs. In one case, a foreign body was retrieved from the duct. No recurrence of clinical signs was noted during the follow-up period (range 21 to 2900 days). CLINICAL SIGNIFICANCE: Parotid duct ectasia should be considered for dogs with a lateralised fluctuant non-painful tubular facial swelling. Surgical management was associated with a favourable prognosis without evidence of recurrence in all cases reported in the case series.

Impact of intra-operative hypotension on mortality rates and post-operative complications in dogs undergoing cholecystectomy.

OBJECTIVES: To report the mortality rate within a cohort of dogs undergoing cholecystectomy and investigate the impact of intra-operative hypotension on mortality. MATERIALS AND METHODS: Clinical records at five UK referral centres were reviewed for dogs undergoing cholecystectomy. Data collected included presenting signs, pre-operative blood test results, intra-operative data including frequency and duration of hypotension and the incidence and type of post-operative complications. RESULTS: Data from 119 dogs were included. Sixteen dogs (13%) died before discharge and by 28 days after surgery the total mortality was 19 dogs (17%). Hypotension lasting over 10 minutes during general anaesthesia occurred in 65 dogs (54.6%), with a mean ± sd duration of 36.1 ± 30.0 minutes. Intra-operative hypotension or the number of hypotensive episodes did not appear to be associated with in-hospital or 28-day mortality. American Society of Anaesthesiologists grade (of fitness for surgery) was significantly associated with both in-hospital and 28-day mortality on univariable analysis, as were post-operative hypoproteinaemia, ileus and pancreatitis. However on multivariable analysis, only ileus and pancreatitis were found to significantly impact mortality. CLINICAL SIGNIFICANCE: Dogs presenting with a higher American Society of Anaesthesiologists grade appear to have a higher risk of mortality, although intra-operative hypotension did not appear to be part of this risk.

The natural history of canine occult Grade II medial patellar luxation: an observational study.

OBJECTIVES: To determine the risk of lameness and the rate of subsequent medial patellar luxation surgery in dogs that present with occult Grade II medial patellar luxation. MATERIALS AND METHODS: Retrospective owner survey and review of clinical records of adult dogs diagnosed with Grade II medial patellar luxation that were initially asymptomatic and managed non-surgically that had a minimum of 4-year follow-up. Clinical notes and owner questionnaires identified dogs that subsequently developed lameness and required surgery on the previously asymptomatic stifle. RESULTS: Thirty-eight dogs were included with an average follow-up of 51 months. Seventeen dogs re-presented for unscheduled contralateral medial patellar luxation surgery at an average of 15 months after initial presentation. A further two dogs had chronic contralateral limb lameness after an average of 33 months after initial surgery and may have been potential surgical candidates. CLINICAL SIGNIFICANCE: Fifty percent of adult dogs presenting with occult Grade II medial patellar luxation subsequently developed chronic lameness or required surgery.

Tick-borne encephalitis (TBE) virus prevalence and virus genome characterization in field-collected ticks (Ixodes ricinus) from risk, non-risk and former risk areas of TBE, and in ticks removed from humans in Germany.

Tick-borne encephalitis (TBE) is recognized as the most important viral tick-borne zoonosis in 27 countries in Europe. In this study, ticks were collected in Germany from two non-risk areas in the states of Saxony-Anhalt and Mecklenburg-Western Pomerania, where several single human TBE cases have occurred in recent years. Ticks were also collected from a region in Thuringia, known to be a former risk area for TBE virus (TBEV), where numerous human cases were reported between 1960 and 1975. Detection of TBEV RNA was conducted by real-time RT-PCR. No TBEV was detected in any field-collected ticks. However, ticks were also collected from volunteers living in Bavaria. Three of 239 ticks from this collection were positive for TBEV genome and two genetically distinct TBEV strains were detected and characterized.

In vivo functional analysis of the daughter of sevenless protein in receptor tyrosine kinase signaling.

One mechanism used by receptor tyrosine kinases to relay a signal to different downstream effector molecules is to use adaptor proteins that provide docking sites for a variety of proteins. The daughter of sevenless (dos) gene was isolated in a genetic screen for components acting downstream of the Sevenless (Sev) receptor tyrosine kinase. Dos contains a N-terminally located PH domain and several tyrosine residues within consensus binding sites for a number of SH2 domain containing proteins. The structural features of Dos and experiments demonstrating tyrosine phosphorylation of Dos upon Sev activation suggested that Dos belongs to the family of multisite adaptor proteins that include the Insulin Receptor Substrate (IRS) proteins, Gab1, and Gab2. Here, we studied the structural requirements for Dos function in receptor tyrosine kinase mediated signaling processes by expressing mutated dos transgenes in the fly. We show that mutant Dos proteins lacking the putative binding sites for the SH2 domains of Shc, PhospholipaseC-gamma (PLC-gamma) and the regulatory subunit of Phosphoinositide 3-kinase (PI3-K) can substitute the loss of endogenous Dos function during development. In contrast, tyrosine 801, corresponding to a predicted Corkscrew (Csw) tyrosine phosphatase SH2 domain binding site, is essential for Dos function. Furthermore, we assayed whether the Pleckstrin homology (PH) domain is required for Dos function and localization. Evidence is provided that deletion or mutation of the PH domain interferes with the function but not with localization of the Dos protein. The Dos PH domain can be replaced by the Gab1 PH domain but not by a heterologous membrane anchor, suggesting a specific function of the PH domain in regulating signal transduction.

Histopathology and molecular basis of iridogoniodysgenesis syndrome.

Iridogoniodysgenesis is an autosomal dominant disorder in which there are abnormalities in the development of the iris stroma and trabecular meshwork tissues commonly resulting in glaucoma. The unoperated eye from an affected member of a family with iridogoniodysgenesis syndrome (IGDS) was removed shortly after death. Histopathological studies showed an incomplete, normally positioned line of Schwalbe and iris stromal hypoplasia. The molecular basis underlying the disorder is a missense mutation in the RIEG gene at 4q25, mutations of which have been previously shown to cause Axenfeld-Rieger syndrome (ARS). Coupled with another report of a missense mutation of the RIEG gene in a family with IGDS, we suggest that these mutations may interfere less with gene function and thereby may be responsible for a milder phenotype than occurs in the more characteristic ARS.

Anomalous patterns of nitroimidazole binding adjacent to necrosis in human glioma xenografts: possible role of decreased oxygen consumption.

In contrast to reports of extensive hypoxia in human gliomas in situ measured by pO2 histography, non-invasive methods of assessing glioma oxygenation, including nitroimidazole binding, have yielded surprisingly contradictory results. In order to investigate the relationship of necrosis, hypoxia, nitroreductase activity and cellular respiration in human gliomas, subcutaneous models using the human glioma cell lines M059K, M006 and M010b were developed in the murine SCID host. Intracranial growth of the M006 line was achieved in nude rats. The nitroreductive capacity of glioma cell lines was assessed and found to be similar to transplanted tumours previously reported in the literature. This suggests that if substantial numbers of viable hypoxic cells were present in situ in gliomas, then nitroimidazole-binding techniques should be capable of identifying them. Inter-tumour variability in the amount of necrosis was seen. M006 xenografts growing in subcutaneous and intracranial sites revealed extensive necrotic regions histologically, some of which were surrounded by cells labelled heavily for [3H]misonidazole, while other areas were lightly labelled. Similar binding patterns were seen for subcutaneous M059K tumours, while subcutaneous M010b tumours display necroses of which almost all were surrounded by heavily labelled cells. The oxygen consumption rates of tumour cell lines grown in vivo, in which venous pO2 concentrations are of the order of 2-5%, were two to sevenfold less than those of the same lines grown as monolayers in vitro under oxygen concentrations of 18%. We postulate that glioma cell lines behave as 'oxygen conformers', in that their rate of oxygen consumption appears to vary with the availability of oxygen. Together with the misonidazole-binding data, the results in this glioma tumour model are consistent with coordinate inhibition or down-regulation of respiration under moderate hypoxia.

Anatomic details of intradural channels in the parasagittal dura: a possible pathway for flow of cerebrospinal fluid.

OBJECTIVE: The absorption of cerebrospinal fluid occurs primarily by means of arachnoid granulations (AG) in the superior sagittal sinus (SSS) and the lacunae laterales (LL) in the parasagittal dura. Previous descriptions of this region suggest a network of intradural channels, but finer details of extent and relationship between channels and AG were not addressed. Therefore, we undertook an anatomic study of cadaveric parasagittal dura. METHODS: The SSS and parasagittal dura of 20 formalin-fixed adult cadavers and 15 autopsy specimens from patients ranging in age from 18 weeks of gestation to 80 years were studied by use of a light microscope, a scanning electron microscope, and corrosion casting. Intradural injections into the parasagittal region were performed in two formalin-fixed and four autopsy specimens from adults by use of normal saline and corrosion casting. RESULTS: Extensive networks of intradural channels from 0.02 to 2.0 mm in diameter were noted in all of the specimens. Channels either were connected to the SSS at intervals along the side wall or drained directly into the LL, which extended up to 3 cm from midline. Channels lined with endothelium stained positive for Factor VIII, as did the endothelium of the LL and SSS. In some places, the network of channels seemed to coalesce to form LL. The underside of the dura was coarse and trabeculated where the channels were abundant, and AG were interdigitated between these trabeculae. In regions of the dura where channels were sparse or absent, the dural underside was smooth and lacked AG. Underlying cortical veins opened directly into the SSS and were unrelated to intradural channels. Intradural parasagittal injections from the epidural side accessed the SSS by way of channels using pressures between 0 and 20 cm H2O at 1.5 ml/min. CONCLUSION: These channels may represent a pathway for the flow of cerebrospinal fluid from AG to the SSS.

Autosomal dominant keratitis: a possible aniridia variant.

OBJECTIVE: To describe the findings in a family with hereditary keratitis. DESIGN: Case series. SETTING: Eye genetics clinic at a university-affiliated hospital in Edmonton. PATIENTS: Fifteen affected members, nine female and six male, of a four-generation family with hereditary keratitis. RESULTS: The pattern of transmission was consistent with autosomal dominant inheritance. The disorder was characterized by the presence of a circumferential band of opacification and vascularization at the level of Bowman's membrane adjacent to the limbus. Progression toward the central cornea occurred in some instances. Penetrating keratoplasty was performed in certain cases when the visual axis was involved and the acuity deteriorated. Histopathological studies confirmed the inflammatory nature and the anterior stromal localization of the keratitis. Thirteen of the affected members in whom a detailed fundus examination was possible had macular hypoplasia. Several had abnormalities of the iris, including iris stromal defects and ectropion uveae. CONCLUSIONS: The presence of macular hypoplasia in association with the iris and corneal changes suggests that autosomal dominant keratitis is likely a variant of aniridia.

Anti-myelin basic protein and anti-proteolipid protein specific forms of multiple sclerosis.

Human myelin basic protein (hMBP) and proteolipid protein (PLP) were used as antigens in a solid-phase radioimmunoassay to determine relative frequencies of anti-MBP and anti-PLP in cerebrospinal fluid (CSF) of optic neuritis and multiple sclerosis (MS) patients. Forty-nine of 55 patients with optic neuritis had increased CSF anti-MBP and the remaining 6 had increased anti-PLP. Of 385 MS patients, MS relapse: 173 of 180 patients had increased anti-MBP, 5 of the remaining 7 patients had elevated anti-PLP, and 2 had neither of these autoantibodies. Progressive MS: 111 of 116 patients had increased anti-MBP in either free and/or bound form, of the remaining 5 patients 4 had increased anti-PLP, and 1 had neither anti-MBP nor anti-PLP. MS remission: 15 of 87 patients had somewhat increased anti-MBP, none had anti-PLP. IgG was purified by affinity chromatography from necropsy central nervous system (CNS) tissue samples of 4 individual patients with clinically definite and neuropathologically confirmed MS. Three of these 4 patients who had increased levels of CSF anti-MBP also had increased anti-MBP titers in CNS tissue-extracted IgG. The fourth patient who had anti-PLP in CSF also had anti-PLP in brain tissue IgG. These autoantibodies were not detected simultaneously in any patient. These results suggest that there are at least two immunologically distinct forms of MS, i.e., a common form highly associated with anti-MBP and more frequent prominent inflammatory characteristics in CSF and CNS, and an infrequent form associated with anti-PLP in CSF and tissue, and less abundant inflammation.(ABSTRACT TRUNCATED AT 250 WORDS)

Fatal rebleeding from a dural arteriovenous malformation of the posterior fossa: case report with pathological examination.

A seventy-year-old woman suffered a fatal cerebellar rehemorrhage from a large venous aneurysm associated with a dural arteriovenous malformation (AVM) of the posterior fossa. The malformation, fed by branches of the right vertebral, occipital and middle meningeal arteries, had a nidus in the transverse sinus wall with a pedunculated extension reaching the pial surface of the adjacent cerebellum, from where the malformation drained exclusively into an aneurysmal cerebellar vein. There was no associated venous sinus obstruction. Histopathological examination of the venous sinuses, arteriovenous malformation and venous drainage is described and these findings as they relate to the pathogenesis of dural AVMs are discussed. Vascular malformations of the dura mater do not appear to be a single clinical or pathological entity. The serious risk of hemorrhage from a parenchymal venous aneurysm is emphasized.

Simulation and analysis of pollen coronas.

By numerical simulation of light scattering by birch and pine pollen grains, we create color plates of coronas with vertical elliptical shapes and strong brightenings, respectively. The shape of the pollen is modeled by the union of n ellipsoids. The Fraunhofer integral is solved by the use of the fast Hartley transform. The sensitivity of the patterns to pollen orientation, Sun elevation, and pollen shape and size is discussed. Good agreement is obtained with amazing photographs made by a Finnish network of amateur astonomers, in the case of strong vertical orientation of the pollen axis.

Cytology of atypical and malignant meningiomas in intraoperative crush preparations.

Six cases of atypical and malignant meningioma studied by intraoperative crush preparations are reported. Four atypical meningiomas were characterized by large cohesive and dyshesive cell clusters showing slightly pleomorphic nuclei and scant cytoplasm. The papillary meningioma yielded dyshesive groups of pleomorphic cells with variable and well-defined cytoplasm. The malignant meningioma, hemangiopericytic type, showed dyshesive cells with scant, ill-defined cytoplasm and spindle-shaped or vesicular nuclei.

Comparison of intrathecal administration of urokinase and tissue plasminogen activator on subarachnoid clot and chronic vasospasm in a primate model.

Safety and efficacy of the thrombolytic agent urokinase (URO) in the elimination of subarachnoid clot and prevention of chronic vasospasm was compared with tissue-type plasminogen activator (rt-PA) in a blind, randomized placebo-controlled trial. Twenty monkeys were randomly assigned to one of five groups of four. Each group underwent baseline cerebral angiography followed by bilateral craniectomy and experimental subarachnoid hemorrhage. An Ommaya reservoir was inserted on the right side with its catheter placed into the ipsilateral subarachnoid space. Twenty-four hours later, depending upon group assignment, the animals received 100,000 IU URO, 200,000 IU URO, 1 mg rt-PA, 2 mg rt-PA, or the equivalent volume of normal saline (control group). On Day 7, angiography was repeated and the animals were killed. One animal died as a result of complications during the baseline angiography, presumably due to blood loss and prolonged anesthesia, and a replacement animal was obtained. No animals demonstrated any delayed neurological deficits. The study demonstrated that a single intracisternal bolus injection of rt-PA, 2.0 mg in 2 ml sterile water, or URO, 200,000 IU in 2 ml sterile water, 24 hours after induction of experimental subarachnoid hemorrhage in primates, was equally effective in thrombolysing ipsilateral clot, but neither dosage prevented angiographic vasospasm. Vasospasm occurred bilaterally in all groups. Whereas gross subarachnoid clot was found bilaterally in all animals in the placebo group and both smaller-dose URO and rt-PA groups, right-sided subarachnoid clot was virtually absent and left-sided clot reduced in both higher-dose URO and rt-PA groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Attempted experimental modification of the postlaminectomy membrane by local instillation of recombinant tissue-plasminogen activator gel.

A prospective, randomized, blinded trial involving 25 adult mongrel dogs was performed to evaluate whether placement of a fat graft or local instillation of recombinant tissue-plasminogen activator gel (rt-PA) could modify the development of a postlaminectomy membrane. One component of the study involved the performance of a lumbar laminectomy and placement of gel rt-PA, free fat, or no tissue placement over the exposed dura mater. Three months later the animals were killed and sections of spine were removed en bloc, decalcified, and examined histologically. No significant differences were found in the degree of cellular fibrosis or heavy collagen production. A similar laminectomy at another lumbar level was also followed by gel rt-PA, free fat, or no tissue placement. Three months after surgery, surgery was performed again at this level immediately before death. There were no differences in the adhesiveness of the laminectomy membrane to dura mater or roots. It was concluded that the local instillation of gel rt-PA after laminectomy did not inhibit scar formation or scar adherence to the dura mater.

Bcl-2 gene rearrangements in primary B-cell lymphoma of the gastrointestinal tract reveal follicular lymphoma as a subtype.

The principal objective of this study was to investigate whether follicular center cell lymphomas occur among B-cell lymphoma of mucosa-associated lymphoid tissue (MALT). We used a molecular genetic/immunohistochemical approach and analysed 21 cases with the primary site in the gastrointestinal tract. Only two bcl-2 gene rearrangements were detected in our series and were found in two out of seven lymphomas with a nodular growth pattern. A chromosomal translocation t(14;18) was demonstrated by comigration of rearranged bcl-2 and JH sequences in one of these two cases. Additionally, both lymphomas showed bcl-2 protein positive neoplastic follicles, CD10 expression, and lack of vimentin. Therefore, these two cases were defined as follicular lymphomas. In contrast to the two follicular lymphomas of MALT, three other, nodular growing, bcl-2 protein positive lymphomas were found to have no bcl-2 gene rearrangements, to be CD10 negative and to express vimentin. These three lymphomas might be composed of neoplastic extrafollicular cells which secondarily invaded reactive follicles. We conclude that the presence of bcl-2 protein positive follicles is consistent with both a follicular and extrafollicular origin of a B lymphoma of MALT. However, the detection of a bcl-2 gene rearrangement is the most valuable criterion in such a situation, and additional immunophenotypic criteria, such as CD10 expression and lack of vimentin within the neoplastic population, further substantiate the diagnosis of a follicular lymphoma in MALT.

Comparative cytomorphology of pituitary adenomas and oligodendrogliomas in intraoperative crush preparations.

Minute fresh tissue fragments from 20 pituitary adenomas and 18 oligodendrogliomas were crushed between two glass slides and stained with hematoxylin and eosin for cytologic examination. These two tumor types displayed distinctive cytologic features that may permit their correct identification. Pituitary adenomas were characterized by single and clustered tumor cells with monomorphic, round or vesicular nuclei that were commonly denuded of cytoplasm. Rare well-preserved tumor cells showed well- or ill-defined, variable and granular cytoplasm. Oligodendrogliomas showed cells with monomorphic or slightly pleomorphic nuclei and scant, fibrillary, wispy cytoplasm, commonly arranged in clusters or around circular and empty spaces.

Increasing radiation dose intensity using hyperfractionation in patients with malignant glioma. Final report of a prospective phase I-II dose response study.

We attempted to show a dose effect relationship for radiation therapy by treating patients harbouring malignant glioma with increasing doses of radiation in a step-wise fashion. We postulated that no increase in delayed toxicity would be seen because we used hyperfractionation technique. Between January 1981 and December 1988 we treated 280 patients three times daily at 4 hour intervals. 100 patients received a total dose of 6141 cGy, 73 patients received 7120 cGy, and 107 patients received 8000 cGy. CCNU was given at the time of tumor progression following radiotherapy. Median time to tumor progression was 28 weeks for patients who received 6141 cGy, 27 weeks for patients who received 7120 cGy and 36 weeks for patients who received 8000 cGy. Median survival was 46 weeks for patients who received 6141 cGy, 38 weeks for patients who received 7120 cGy and 45 weeks for patients who received 8000 cGy. There was no statistically significant difference in either time to tumor progression or survival among the three treatment arms and no dose response effect was seen. There was no increase in delayed radiation toxicity when the total radiation dose was increased up to 8000 cGy.