Deregulation of signalling in genetic conditions affecting the lysosomal metabolism of cholesterol and galactosyl-sphingolipids

The role of lipids in neuroglial function is gaining momentum in part due to a better understanding of how many lipid species contribute to key cellular signalling pathways at the membrane level. The description of lipid rafts as membrane domains composed by defined classes of lipids such as cholesterol and sphingolipids has greatly helped in our understanding of how cellular signalling can be regulated and compartmentalized in neurons and glial cells. Genetic conditions affecting the metabolism of these lipids greatly impact on how some of these signalling pathways work, providing a context to understand the biological function of the lipid. Expectedly, abnormal metabolism of several lipids such as cholesterol and galactosyl-sphingolipids observed in several metabolic conditions involving lysosomal dysfunction are often accompanied by neuronal and myelin dysfunction. This review will discuss the role of lysosomal biology in the context of deficiencies in the metabolism of cholesterol and galactosyl-sphingolipids and their impact on neural function in three genetic disorders: Niemann-Pick type C, Metachromatic leukodystrophy and Krabbe’s disease.

Printed titanium implants in UK craniomaxillofacial surgery. Part I: access to digital planning and perceived scope for use in common procedures

This first part of a two-part study examines perceived applications for and barriers to using printed titanium in light of current caseloads, funding pathways, and use of digital planning. It aims to demonstrate the scope for printed titanium in modern practice and to guide industry about the needs of UK surgeons. A cross-sectional study over 14 weeks was performed electronically with support from the British Association of Oral and Maxillofacial Surgeons (BAOMS) and a national trainee-led recruitment team. Ethics approval was obtained at the lead centre. A total of 132 participants joined the study (70% consultants, 25% specialty registrars, and 5% other), approximating a 29% response rate from consultant/registrar BAOMS members throughout mainland UK. Eighty-eight per cent used CAD-CAM design, with highly variable funding/access, design/manufacturing workflows (in-house/outsourced). Eighty-eight per cent were involved with trauma, 61% with orthognathic, and 52% with oncology-reconstruction surgery. Favourite applications for printed titanium were orbital floor repair (89%) and free-flap jaw reconstruction (87%). Most participants also cited maxillary/zygomatic osteotomies and cranioplasty (range 61%-73%). Although a popular application (78%), the evidence base in temporomandibular joint surgery is limited. Those performing orthognathic surgery perceived more indications than those who did not (p=0.013). Key barriers included cost, turnaround time and logistics, and the need to be trained in traditional techniques. Printed titanium was useful for both common and niche procedures, but was specifically limited in emergency trauma. Most surgeons had experience in CAD-CAM surgery but technical understanding appeared unclear. Limiting factors included variable funding and production pathways, perceived costs, and logistics, but in-house design can minimise them. In part II, we quantify perceived benefits and limitations and whether surgeons' understanding and knowledge are sufficient to rationalise them.

Printed titanium implants in UK craniomaxillofacial surgery. Part II: perceived performance (outcomes, logistics, and costs)

This second part explores perceptions and understanding of clinical performance, turnaround, and costs for printed titanium implants or plates in common procedures, evaluating both 'in-house' and 'outsourced' CAD-CAM pathways. A cross-sectional study, supported by the British Association of Oral and Maxillofacial Surgeons (BAOMS) and a national trainee-led recruitment team, was conducted over 14 weeks. A total of 132 participants took part (demographic data is reported in Part I). For fibular-flap mandibular reconstruction, most participants (69% - 91%) perceived printed titanium as superior to intraoperatively or preoperatively hand-bent plates for surgical duration, accuracy, dental restorability, and aesthetics. There was less agreement about complications and plate-failure risks. Most perceived printed plates to be superior to traditional wafer-based maxillary osteotomy for surgical duration (61%) and maxillary positioning (60%). For orbital floor repair, most perceived improvements in surgical duration (83%, especially higher-volume operators p=0.009), precision (84%), and ease of placement (69%). Rarely (less than 5%) was any outcome rated inferior to traditional techniques for any procedure. Perceived turnaround times and costs were variable, but the greatest consensus was for two-segment fibular-flap reconstructions and orbital floor repair. Industry estimates were generally consistent between two company representatives, but manufacturing-only costs differed when using in-house (departmental) designers. Costs and turnaround times are questionable barriers since few understand 'real-world' figures. Designing in-house can dramatically alter costs. Improved accuracy and surgical duration are common themes but biomechanical benefits are less-well understood. This study paints a picture of the potentially routine applications and benefits of printed titanium, capacity for uptake, understanding amongst surgeons, and areas for improvement.

Dirofilaria hongkongensis - A first report of potential zoonotic dirofilariosis infection in dogs from Tamil Nadu

Dirofilariosisis, is a mosquito borne anthropo-zoonotic disease caused by the filarial nematodes of the genus Dirofilaria. The current paper reports a species of Dirofilaria, which has not been recorded in Tamil Nadu, in addition to differentiating it from the existing species of Dirofilaria spp. through morphological and molecular techniques. Micrometry of the microfilaria detected by Knott's technique as well as in Giemsa stained blood smears revealed that the length was on an average 280 μm to 310 μm whereas the width was 5 to 8 μm. The microfilariae were unsheathed with blunt heads and tapering tails. For molecular confirmation, the blood sample was subjected to genomic DNA isolation. PCR amplification using specific primers for D. hongkongensis was carried out using thermal cycler with the isolated genomic DNA as template. Molecular analyses revealed the band size of about 230 bp which confirmed the presence of D. hongkongensis. Phylogenetic analysis was done using UPGMA and MLM method. Dirofilaria is recognized as a zoonotic entity throughout the world, and dirofilariasis should be considered an emerging zoonosis in southern India. The control of ubiquitous mosquito population is essential to prevent the transmission of microfilaria from animals to arthropods and from arthropods to humans.

Comparison of in-vitro bioassays for evaluation of the response of different stages of Rhipicephalus sanguineus sensu lato to calcium alginate encapsulated pheromone beads

Tick sex pheromone (SP), assembly pheromone (AP) and their combination (SP + AP) were encapsulated in calcium alginate beads. In vitro bioassays, namely Petri dish and olfactometer assays, were employed to estimate the level of attraction of the various stages of Rhipicephalus sanguineus sensu lato, namely unfed and engorged (fed) larvae, nymphs, females, and males to the different pheromones. The study revealed that only the Petri dish assay was suitable to evaluate the response of larval stages whereas the olfactometer bioassay could also be used for evaluating the response of all other stages. Attraction to pheromone encapsulated calcium alginate beads of all tick stage was higher in the Petri dish assay than in the olfactometer assay.

Collapsing Glomerulopathy Superimposed on Diabetic Nephropathy

Diabetic nephropathy (DN) is characterized by gradually progressive renal failure and proteinuria. Various types of nondiabetic kidney diseases may superimpose on DN, and affect the natural course, prognosis, and management. Collapsing glomerulopathy (CG) is a form of glomerular proliferative injury, characterized by rapid progression and associated with poor prognosis. CG may be idiopathic or secondary to other causes, and it has also been described with other forms of glomerular diseases. The association of CG with DN has not been reported widely. We report on a patient with DN who has undergone renal biopsy due to massive proteinuria and rapid loss of renal function. Renal biopsy was suggestive of CG superimposed on DN. He was treated conservatively, however, progressed to end-stage renal disease rapidly.

Effects of patchouli and cinnamon essential oils on biofilm and hyphae formation by Candida species

The prevalence and fatality rates with biofilm-associated candidal infections have remained a challenge to the medical fraternity despite major advances in the field of antifungal therapy. Traditionally, essential oils (EOs) from the aromatic plants have been found to be excellent therapeutic agents to treat fungal ailments. The present study explores the antivirulent and antibiofilm effects of under explored leaf EOs of Indian patchouli EO extracted from Pogostemon heyneanus (PH), Indian cassia from Cinnamomum tamala (CT) and camphor EO from C. camphora (CC) against Candida species. The EOs were investigated for its efficacy to disrupt the young and preformed Candida spp. biofilms and to inhibit the yeast to hyphal transition, a hallmark virulent trait of C. albicans. The ability of these EOs to inhibit metabolically active cells was assessed through XTT assay. Of these three EOs, CT EO showed enhanced biofilm inhibition than others and hence it was further selected to study its biomass inhibition potential and exopolysaccharide layer disruption ability. The CT EO reduced the biomass of the preformed biofilms of all three Candida strains, which was supported by confocal microscopy. It also disrupted the exopolysaccharide layer of the Candida strains as shown by scanning electron microscopy. The present findings validate the effectiveness of EOs against the virulence of Candida spp. and emphasize the pharmaceutical potential of several native but yet unexplored wild aromatic plants in the prospect of therapeutic application.

Plasma Cell Infiltration of the Kidney as a Manifestation of Myeloma: A Report of Three Cases

Infiltration of renal parenchyma by neoplastic plasma cells in myeloma patients is an unusual finding. We report 3 cases of myeloma, with renal biopsy being the first clue to the diagnosis in one. The plasma cell infiltrate in other two cases was not so evident but immunofluorescence (IF) and immunohistochemical (IHC) stains for light chains helped establish the monoclonal nature of the infiltrate. We surmise that plasma cell infiltration in the kidney can be an important clue to the diagnosis of an underlying myeloma and could in future be regarded as a myeloma-defining event (MDE) if monoclonality is confirmed. This finding could directly affect the prognosis and be a direct indicator of the tumor burden. Further studies are however required to determine the exact prognostic value and precise relationship of such a finding with deranged renal functions in myeloma.

An unusual case of nephrotic syndrome

Nephrotic syndrome can be rarely due to inherited disorders of enzymes. One such variety is lecithin cholesterol acyltransferase deficiency. It leads to accumulation of unesterified cholesterol in the eye and other organs. We report a case of nephrotic syndrome with cloudy cornea and hypocholesterolemia with foam cells and lipid deposits on renal biopsy. Awareness about this rare disease may help in the early institution of specific measures to prevent progression to end-stage renal disease.

Proliferative glomerulonephritis associated with monoclonal immune deposits: A case report and review of literature

Proliferative glomerulonephritis with monoclonal IgG deposits (PGNMID) is a newly recognized entity caused by monoclonal deposition of IgG. PGNMID resembles immune complex glomerulonephritis (GN) on light and electron microscopy. The monotypic immunoglobulin deposits seen on immunofluorescence (IF) clinches the diagnosis. We report a case of proliferative GN associated MGRS and review the relevant literature. The patient had significant proteinuria and elevated serum creatinine. The renal biopsy showed proliferative GN with focal crescents and monoclonal immune deposits confirming a diagnosis of PGNMID. Serum work up showed no monoclonal proteins. Proliferative GN as a manifestation of a monoclonal gammopathy needs to be borne in mind especially in renal biopsies of older patients.

ARID1B, a member of the human SWI/SNF chromatin remodeling complex, exhibits tumour-suppressor activities in pancreatic cancer cell lines

Background:

The human ATP-dependent SWItch/sucrose nonfermentable (SWI/SNF) complex functions as a primary chromatin remodeler during ontogeny, as well as in adult life. Several components of the complex have been suggested to function as important regulators of tumorigenesis in various cancers. In the current study, we have characterised a possible tumour suppressor role for the largest subunit of the complex, namely the AT-rich interaction domain 1B (ARID1B).

Methods:

We performed Azacytidine and Trichostatin A treatments, followed by bisulphite sequencing to determine the possible DNA methylation-induced transcription repression of the gene in pancreatic cancer (PaCa) cell lines. Functional characterisation of effect of ARID1B ectopic expression in MiaPaCa2 PaCa cell line, which harboured ARID1B homozygous deletion, was carried out. Finally, we evaluated ARID1B protein expression in pancreatic tumour samples using immunohistochemistry on a tissue microarray.

Results:

ARID1B was transcriptionally repressed due to promoter hypermethylation, and ectopic expression severely compromised the ability of MiaPaCa2 cells to form colonies in liquid culture and soft agar. In addition, ARID1B exhibited significantly reduced/loss of expression in PaCa tissue, especially in samples from advanced-stage tumours, when compared with normal pancreas.

Conclusion:

The results therefore suggest a possible tumour-suppressor function for ARID1B in PaCa, thus adding to the growing list of SWI/SNF components with a similar function. Given the urgent need to design efficient targeted therapies for PaCa, our study assumes significance.

Renal disease in human immunodeficiency virus - Not just HIV-associated nephropathy

The aim of the study was to determine the various histopathological lesions in human immunodeficiency virus (HIV) patients with renal dysfunction and to establish clinicopathological correlation. Over a period of two years from January 2008 to March 2010, 27 HIV positive patients with renal dysfunction were subjected to renal biopsy. Of the 27 patients, 23 were males and four were females (85.2% males, 14.8% females). Mean age was 38.2 ± 10.36 (range 20 – 60) years. The probable mode of acquisition of HIV infection was sexual in 22 patients (81.5%). Thirteen patients (48%) had nephrotic proteinuria. The CD4 count ranged from 77 to 633/microliter. The kidneys were of normal size in 19 (70.4%) and bulky in eight (29.6%) patients. Thirteen patients required renal replacement therapy. Eleven patients had acute tubule-interstitial lesions (40.7%) while 15 (55.5%) had glomerular lesions. The various glomerular lesions were, focal segmental glomerulosclerosis in five, amyloidosis in three, diffuse proliferative GN in two, and membranoproliferative glomerulonephritis (GN), membranous GN, minimal change disease, diabetic nephropathy, crescentic GN, and thrombotic microangiopathy were seen in one each. None of the clinical or laboratory variables, except hypertension, was found to predict glomerular versus non-glomerular lesions on biopsy. In conclusion we show that a variety of glomerular and tubulointerstitial lesions can be seen on renal histology. Hence, renal biopsy is indicated in renal dysfunction associated with HIV for making proper diagnosis and therapy.

Sex-based differences in lupus nephritis: a study of 235 Indian patients

BACKGROUND

This study was carried out to analyze clinical presentation, laboratory parameters and histology in lupus nephritis in males in comparison with females.

METHODS

Patients diagnosed with lupus nephritis between January 2001 and December 2005 were divided into 2 groups: males and females, and were analyzed with regard to clinical presentation, renal profile, serology and histology. All biopsies were reported by a single histopathologist as per WHO classification. Activity and chronicity indices were calculated. Comparison was made between the 2 groups. Statistical analysis was done using Strata version 6 software for Windows.

RESULTS

Of the 235 patients diagnosed to have lupus nephritis, 35 were males (14.9%) and 200 females (85.1%). Males were younger (mean age 23.22 +/- 9.32 years, range 9-44) compared with females (mean age 24.7 +/- 8.93 years, range 5-55). Extrarenal manifestations such as joint pains, alopecia, rash, fever, serous effusions and oral ulcers were comparable in both groups, as were hypertension (68.5% vs. 67%), nephrotic proteinuria (40% vs. 36%) and hematuria (80% vs. 73%). Renal dysfunction was significantly more common in males (60% vs. 37.5%, p<0.05) with higher levels of mean serum creatinine (2.67 vs. 1.62 mg/dL, p<0.05) and blood urea (63.25 vs. 48 mg/dL, p<0.01). Histologically, class IV lupus was the most common lesion in both groups (71.4% in males, 60% in females). Membranous lupus nephritis was more common in females (22% vs. 5.7%, p<0.05). Activity index (8.51 vs. 6.76, p<0.05) was higher in males.

CONCLUSIONS

Renal dysfunction and activity index are significantly higher in male patients with lupus nephritis.

Paroxysmal nocturnal haemoglobinuria in Indians

Paroxysmal nocturnal haemoglobinuria (PNH) was diagnosed in 11 patients attending the haematology clinic of a private community hospital in Hyderabad, India over a 3-year period. Compared to PNH occurring in Caucasians, the patients were younger, and showed a marked male preponderance; severe thrombocytopenia, haemorrhagic complications from thrombocytopenia and infectious complications were not seen. Thrombotic complications were common. Fever during periods of haemoglobinuria was a notable feature in 4 patients. None of the patients had the aplastic anaemia PNH syndrome.