A cadaveric anatomical study of the adrenals: Relationship with the posterior abdominal wall muscles revisited

AIM OF THE STUDY

The main difficulties during retroperitoneal laparoscopic adrenalectomies are due to its location. Our objective was to define the relationship of the adrenals with the diaphragm and the psoas muscle.

METHODS

Our work is an anatomical dissection of 80 fresh cadavers' adrenals. To study the right adrenal, we performed a right nephrectomy and adrenal remained attached to the Inferior vena cava by its main vein. On the left, the edges of the adrenal have been identified by needles and the adrenal was reclined to study its projection on the posterior muscular wall.

RESULTS

The right adrenal is located higher, 13mm [4-20mm] above the medial arcuate ligament (MAL) in 16 cases (40%). Its lower border was at the same level as the MAL in 18 cases (45%) and 11mm [10-17mm] below the MAL in 6 cases (15%). The posterior support of the right adrenal was the right crus of the diaphragm (Right-CD) in 34 cases (85%) and straddling the Right-CD and the psoas in 6 cases (15%). The study of the relationships of the left adrenal with the MAL showed that the lower edge of the gland was at its same level in 16 cases (40%) and below in 24 cases (60%) by 14mm [8-24mm]. The posterior support of the left adrenal was the left crus of the diaphragm (Left-CD) in 16 cases (40%) and straddling the Left-CD and the psoas in 24 cases (60%).

CONCLUSIONS

Our results showed that the right adrenal is higher. The MAL is an important posterior element to the adrenal gland that could serve as an anatomical landmark to identify the adrenal during laparoscopic adrenalectomy.

Static and dynamic properties of decane/water microemulsions stabilized by cetylpyridinium chloride cationic surfactant and octanol cosurfactant

Molecular dynamics simulation (MD) is used to study the static and dynamic properties of positively charged decane/water microemulsions, for various volume fractions Φ (2.8%, 6.98%, 14%, and 26.5%). An effective hybrid potential combining three potentials, namely the hard-sphere repulsive potential, the van der Waals attractive potential, and the Yukawa repulsive potential, is used to describe the microemulsion interactions. The microemulsion shape is determined using the renormalized spectra in Porod representation. The appropriate potential parameters are tested using the Ornstein–Zernike integral equation approach with the Hypernetted Chain (HNC) closure relation by a comparison between the structure factor calculated from HNC and that obtained from Small Angle Neutron Scattering experiments (SANS). Thus, the micro arrangements of microemulsions have been analyzed using the pair correlation function g(r) and the structure factor S(q) obtained from HNC, SANS, and MD simulation using these parameters. The microemulsion dynamic properties were discussed using the mean-square displacement (MSD) and the diffusion coefficient D_c calculated from MD simulations.

We report a molecular dynamics simulation using a proven effective interaction potential to study the physical properties of decane/water microemulsions.

The Exo-Polysaccharide Component of Extracellular Matrix is Essential for the Viscoelastic Properties of Bacillus subtilis Biofilms

Bacteria are known to form biofilms on various surfaces. Biofilms are multicellular aggregates, held together by an extracellular matrix, which is composed of biological polymers. Three principal components of the biofilm matrix are exopolysaccharides (EPS), proteins, and nucleic acids. The biofilm matrix is essential for biofilms to remain organized under mechanical stress. Thanks to their polymeric nature, biofilms exhibit both elastic and viscous mechanical characteristics; therefore, an accurate mechanical description needs to take into account their viscoelastic nature. Their viscoelastic properties, including during their growth dynamics, are crucial for biofilm survival in many environments, particularly during infection processes. How changes in the composition of the biofilm matrix affect viscoelasticity has not been thoroughly investigated. In this study, we used interfacial rheology to study the contribution of the EPS component of the matrix to viscoelasticity of Bacillus subtilis biofilms. Two strategies were used to specifically deplete the EPS component of the biofilm matrix, namely (i) treatment with sub-lethal doses of vitamin C and (ii) seamless inactivation of the eps operon responsible for biosynthesis of the EPS. In both cases, the obtained results suggest that the EPS component of the matrix is essential for maintaining the viscoelastic properties of bacterial biofilms during their growth. If the EPS component of the matrix is depleted, the mechanical stability of biofilms is compromised and the biofilms become more susceptible to eradication by mechanical stress.

Importance of protein Ser/Thr/Tyr phosphorylation for bacterial pathogenesis

Protein phosphorylation regulates a large variety of biological processes in all living cells. In pathogenic bacteria, the study of serine, threonine, and tyrosine (Ser/Thr/Tyr) phosphorylation has shed light on the course of infectious diseases, from adherence to host cells to pathogen virulence, replication, and persistence. Mass spectrometry (MS)-based phosphoproteomics has provided global maps of Ser/Thr/Tyr phosphosites in bacterial pathogens. Despite recent developments, a quantitative and dynamic view of phosphorylation events that occur during bacterial pathogenesis is currently lacking. Temporal, spatial, and subpopulation resolution of phosphorylation data is required to identify key regulatory nodes underlying bacterial pathogenesis. Herein, we discuss how technological improvements in sample handling, MS instrumentation, data processing, and machine learning should improve bacterial phosphoproteomic datasets and the information extracted from them. Such information is expected to significantly extend the current knowledge of Ser/Thr/Tyr phosphorylation in pathogenic bacteria and should ultimately contribute to the design of novel strategies to combat bacterial infections.

Precontrolled Alignment of Graphite Nanoplatelets in Polymeric Composites Prevents Bacterial Attachment

Graphene coatings composed of vertical spikes are shown to mitigate bacterial attachment. Such coatings present hydrophobic edges of graphene, which penetrate the lipid bilayers causing physical disruption of bacterial cells. However, manufacturing of such surfaces on a scale required for antibacterial applications is currently not feasible. This study explores whether graphite can be used as a cheaper alternative to graphene coatings. To examine this, composites of graphite nanoplatelets (GNP) and low-density polyethylene (LDPE) are extruded in controlled conditions to obtain controlled orientation of GNP flakes within the polymer matrix. Flakes are exposed by etching the surface of GNP-LDPE nanocomposites and antibacterial activity is evaluated. GNP nanoflakes on the extruded samples interact with bacterial cell membranes, physically damaging the cells. Bactericidal activity is observed dependent on orientation and nanoflakes density. Composites with high density of GNP (≥15%) present two key advantages: i) they decrease bacterial viability by a factor of 99.9999%, which is 10 000-fold improvement on the current benchmark, and ii) prevent bacterial colonization, thus drastically reducing the numbers of dead cells on the surface. The latter is a key advantage for longer-term biomedical applications, since these surfaces will not have to be cleaned or replaced for longer periods.

Comparative genomics study reveals Red Sea Bacillus with characteristics associated with potential microbial cell factories (MCFs)

Recent advancements in the use of microbial cells for scalable production of industrial enzymes encourage exploring new environments for efficient microbial cell factories (MCFs). Here, through a comparison study, ten newly sequenced Bacillus species, isolated from the Rabigh Harbor Lagoon on the Red Sea shoreline, were evaluated for their potential use as MCFs. Phylogenetic analysis of 40 representative genomes with phylogenetic relevance, including the ten Red Sea species, showed that the Red Sea species come from several colonization events and are not the result of a single colonization followed by speciation. Moreover, clustering reactions in reconstruct metabolic networks of these Bacillus species revealed that three metabolic clades do not fit the phylogenetic tree, a sign of convergent evolution of the metabolism of these species in response to special environmental adaptation. We further showed Red Sea strains Bacillus paralicheniformis (Bac48) and B. halosaccharovorans (Bac94) had twice as much secreted proteins than the model strain B. subtilis 168. Also, Bac94 was enriched with genes associated with the Tat and Sec protein secretion system and Bac48 has a hybrid PKS/NRPS cluster that is part of a horizontally transferred genomic region. These properties collectively hint towards the potential use of Red Sea Bacillus as efficient protein secreting microbial hosts, and that this characteristic of these strains may be a consequence of the unique ecological features of the isolation environment.

Retro-peritoneal paraganglioma, diagnosis and management

INTRODUCTION

Paragangliomas, defined as extra-adrenal chromaffin-cells tumors, are rarely located in the retro-peritoneum. Clinical presentation is similar to pheochromocytoma, and mainly depends on the producing character of the tumor. Positive diagnosis requires plasmatic and urinary hormonal assays. Radiological and isotopic explorations are essential before surgery. The only curative therapeutic strategy is surgical, associated to peri-operative prevention and monitoring of the frequently reported hemodynamic and cardiovascular disorders. Outcome depends of the metastatic character of the tumor, the presence of tumor remnant after surgical resection. Genetic study is recommended; the risk of recurrence and association to other neoplasm is more described in genetic forms.

MATERIAL AND METHODS

Authors report 5cases of retro-peritoneal paraganglioma, operated in the department of urology of Hospital, between 2013 and 2017. Observations are about 2men and 3women. Clinical presentation is not always specific and paraganglioma may be discovered fortuitously. Two patients have been operated by coelioscopic approach, midline incision was performed in two other cases, and dorsal lumbotomy associated to a Rutherford-Morrison incision in a patient.

RESULTS

Two patients presented resistant hypertension and palpitation associated to suspect retro-peritoneal masses in imagery and elevated urinary methoxylated derivates before surgery. One patient was asymptomatic and the tumor was discovered in imagery. Per-operative hypertensive crisis and sinus tachycardia occurred in a case. The average follow-up period is 22.8months. Hypertension and palpitation disappeared after surgery. There was no recurrence for all the operated patients.

CONCLUSION

Retro-peritoneal paraganglioma is a rare condition. Symptoms are not specific and clinical presentation may be similar to pheochromocytoma. Abdominal CT-scan and MRI, in association with MIBG scintigraphy are strongly evocative. Histological examination ensures diagnosis. Per-operative cardio-vascular disorders are to consider and must prevented and managed by anesthesiologists. Complete surgical resection is the only curative treatment and avoids recurrences.

Splenogonadal fusion - a rare cause of scrotal swelling: a case report

Background

Splenogonadal fusion is a rare and benign condition. Diagnosis is challenging for clinicians. Despite its indolence, diagnosis is often confirmed after orchidectomy. Surgery is mandatory, particularly to rule out the extremely rare association with malignancy.

Case presentation

We report a case of splenogonadal fusion in a 38-year-old North African man presenting a palpable scrotal mass. We describe clinical aspects, pathogenic hypothesis, radiological features, as well as surgical management principles.

Conclusions

Splenogonadal fusion is rarely suspected and diagnosed preoperatively. A diagnosis is made once an ectopic testicular mass is associated with cryptorchidism and suggestive radiological signs. A better knowledge of the clinical and radiological features of splenogonadal fusion provides an opportunity for conservative surgery.