mostafa hajinasrollah

The sensory and mobility failure associated with spinal cord injury (SCI) is desperately complicated due to the pathological events that occur sequentially in consequent to the injury.

Herein, we applied neural stem cells, derived from human iPSCs (hiPSC-NSCs), to ameliorate the behavioral complications of contusive SCI in Rhesus monkeys, in sub-acute phase.

hiPSC-NSCs were maintained and characterized in vitro for general NSCs as well as hind-limb specific gene and protein expression prior to transplantation. Moreover, Masson's trichrome staining (MTS) in addition to luxol fast blue (LFB) were performed to determine the fibrotic scar reduction and myelination respectively. Tarlov’s scale were utilized to score the motor improvement, plus, sensory perception evaluation throughout six months following the injury.

hiPSC-NSCs were identified to own NSCs’ exclusive properties in vitro by SOX2, DCX and NESTIN in addition to NESTIN , PAX6 , SOX1 , HOXA2 and HOXB2 protein and gene expression. Additionally, hiPSC-NSCs caused remarkable depletion in fibrotic scar and enhance myelination; spinal shock, sensory responses, reflexes and motor function were improved over six months.

Our findings suggest that hiPSC-NSCs lead to promising recovery after SCI, therefore, this source of NSCs provide a therapeutic potential in clinical studies.

In vivo neural recordings from primates require the installation of implants on the skull of the animal. Despite some improvements, current routines risk predisposition to infection and failure or impose constant discomfort by placing heaviness on the top of the head.

A custom-designed imaging adapter was obtained by magnetic resonance and computerized tomography (CT) imaging of the head region. Then, based on a reconstructed skull model, the implants were designed and constructed using a computer numerical control (CNC) machine. During the surgical operation, the position of each implant was sketched on the skull, and implants were slipped onto their predicted site, following their sketched boundaries without any manual reshaping. 

We have performed this procedure on two monkeys. After surgery, the location of the implants has been verified by CT imaging. The recovery period was without significant complications with minimal infection.

Our experiment showed that applying an image-guided design makes it possible to utilize the skull area better and gain access to brain regions. At the same time, our method reduced the possibility of gap formation between the implant and skull open skin margins. It reduces the time and cost of operation, resulting in a reduced chance of infection and failure, and provides animal-friendly operational surgery procedures. Despite some improvements, more refinements of methodology are still required. Here, we propose and report an improvement in the design and installation of low-cost biocompatible implants providing access to at least three brain regions.

Animal models provide a deeper understanding about various complications and better demonstrate the effect of therapeutic approaches. One of the issues in the low back pain (LBP) model is the invasiveness of the procedure and it does not mimic actual disease conditions in humans. The purpose of the present study was to compare the ultrasound-guided (US-guided) percutaneous approach with the open-surgery method in the tumor necrosis factor-alpha (TNF-α)-induced disc degeneration model for the first time to showcase the advantages of this recently developed, minimally invasive method.

In this experimental study, eight male rabbits were divided into two groups (open-surgery and US-guided). Relevant discs were punctured by two approaches and TNF-α was injected into them. Magnetic resonance imaging (MRI) was performed to assess the disc height index (DHI) at all stages. Also morphological changes (annulus fibrosus, nucleus pulposus) were evaluated by assessing Pfirrmann grade and histological evaluation (Hematoxylin & Eosin).

The findings indicated targeted discs became degenerated after six weeks. DHI in both groups was significantly reduced (P<0.0001), however the difference was not significant between the two groups. In the open-surgery group, osteophyte formation was seen at six and eighteen weeks after the puncture. Pfirrmann grading revealed significant differences between injured and adjacent uninjured discs (P<0.0001). The US-guided method indicated significantly fewer signs of degeneration after six (P=0.0110) and eighteen (P=0.0328) weeks. Histological scoring showed significantly lower degeneration in the US-guided group (P=0.0039).

The US-guided method developed a milder grade condition and such a model better mimics the chronic characteristics of LBP and the procedure is more ethically accepted. Therefore, the US-guided method could be a merit approach for future research in this domain as a safe, practical and low-cost method. 

 Scarcity of oocytes for assisted reproduction in endangered species can be bypassed by interspecies somatic cell nuclear transfer (iSCNT). In Felids, domestic cat (Felis catus) oocytes can serve as recipients for the nucleus of the endangered Persian leopard (Panthera pardus saxicolor). However, in vitro oocyte maturation is still suboptimal in cats, whereas it has been reported to benefit from micro-vibration in non-felid species. Therefore, the present study is aimed to determine whether micro-vibration, applied during in vitro maturation (IVM), improves the embryogenic potential of cat oocytes transplanted with fibroblast nuclei of the Persian leopard.

 In the experimental study, cat cumulus-oocyte complexes (COCs) were randomly assigned to the treatment group (micro-vibration) or control group (static culture). Resultant metaphase II (MII) oocytes were enucleated and reconstructed with nucleus transplants from leopard fibroblasts, followed by artificial oocyte activation and embryo culture under the same condition (static) for 7 days.

 While cumulus cell expansion and oocyte maturation profited from micro-vibration (P<0.05), the quantity and quality of blastocysts were significantly lower in micro-vibration than in the control group (P<0.05). The total number of blastocyst cells tended to be lower in the micro-vibration than in the control group (P=0.075). Nevertheless, the proportion of ICM and TE cells did not differ between the micro-vibration and control groups (P>0.05).

 The present study indicated that micro-vibration at a frequency of 44 Hz for 5 secs per hour enhanced nuclear maturation and cumulus cell expansion of cat oocytes. However, exposure to micro-vibration during IVM impaired the survival rate of reconstructed oocytes during the iSCNT process and their developmental competence toward the blastocyst stage.

There have been many reports on spinal cord injuries in humans and animals, which is  a major medical and veterinary concern; therefore, the present research project was carried out to devise an appropriate treatment approach.

The purpose of the present study was to apply the modified Allen’s test and Royan Impactor Devicein order to 1) induce spinal cord injury on rhesus monkeys and 2) gain the ultimate confirmation by clinical examinations and MR imaging for application in human and veterinary medicine.

Royan Impactor Device  was used to induce spinal cord injury on rhesus monkeys. Five rhesus monkeys were anesthetized with ketamine, xylazine, and isoflurane. Laminectomy  was done at the level of T9-T10, and a 50 g weight was then dropped from a 12 cm height through a guide tube onto a 10 mm2 impact plate on the exposed spinal cord.

The results of the present study showed signal changes with decreasing the trend in the T2W of spinal cord in sagittal and axial areas due to hematoma, inflammation, pressure on spinal cord, and tissue destruction after spinal cord injury. In the clinical examination of all samples, spinal cord shock symptoms, marked by bladder distention, disappeared 3-5 days post spinal cord injury. Not all measurable factors related to the severity of the injury  were restored to the normal condition until the end of the study although their severities were reduced to some extend.

Modified Allen’s test and the instrument that we designed for this study were able to satisfy the needs of the researchers in treating the spinal cord injury.

In the present study, we examined the tolerance-inducing effects of human adipose-derived mesenchymal stem cells (hAD-MSCs) and bone marrow-derived MSCs (hBM-MSCs) on a nonhuman primate model of skin transplantation.

In this experimental study, allogenic and xenogeneic of immunomodulatory properties of human AD-MSCs and BM-MSCs were evaluated by mixed lymphocyte reaction (MLR) assays. Human MSCs were obtained from BM or AD tissues (from individuals of either sex with an age range of 35 to 65 years) and intravenously injected (2×106 MSCs/kg) after allogeneic skin grafting in a nonhuman primate model. The skin sections were evaluated by H&E staining for histopathological evaluations, particularly inflammation and rejection reaction of grafts after 96 hours of cell injection. At the mRNA and protein levels, cellular mediators of inflammation, such as CD4+IL-17+ (T helper 17; Th17) and CD4+INF-γ+ (T helper 1, Th1) cells, along with CD4+FoxP3+ cells (Treg), as the mediators of immunomodulation, were measured by RT-PCR and flow cytometry analyses.

A significant Treg cells expansion was observed in MSCs-treated animals which reached the zenith at 24 hours and remained at a high concentration for 96 hours; however, Th1 and Th17 cells were significantly decreased. Our results showed that human MSCs significantly decrease Th1 and Th17 cell proliferation by decreasing interleukin-17 (IL-17) and interferon-γ (INF-γ) production and significantly increase Treg cell proliferation by increasing FoxP3 production. They also extend the allogenic skin graft survival in nonhuman primates. Histological evaluations showed no obvious presence of inflammatory cells or skin redness or even bulging after MSCs injection up to 96 hours, compared to the group without MSCs. There were no significant differences between hBM-MSCs and hAD-MSCs in terms of histopathological scores and inflammatory responses (P<0.05).

It seems that MSCs could be regarded as a valuable immunomodulatory tool to reduce the use of immunosuppressive agents.

A secondary ectopic pregnancy is defined as continuing development of a fetus in the abdominal cavity after rupture of the uterine wall, which may be associated with a history of trauma.

A cat was referred to the veterinary teaching hospital of the University of Tehran with history of anorexia and vaginal bleeding. In clinical examination some masses werepalpated in abdominal cavity so the patient wasreferred to radiology and sonography for definite diagnoses. In ultrasonography examination three dead fetuses were detectedoutside the uterus. In US it so appeared that gestational sacs did not cover the fetuses and there was a rupture in cranial part of right uterine horn that made the case highly suspected to ectopic pregnancy caused by trauma.  

Therefore the cat was prepared for aseptic surgery and anesthetized with isofulorane. After incision of the lineaalba three fetuses were seen outside the uterus that wereattached to abdominal wall (left and right wall) and mesentery. There was no sign ofgestational sac to cover the fetuses. The three fetuses were bluntly dissected from the attachments and all conspicuous vessels were ligated and the fetuses were removed. Ovariohysterectomy was also performed to prevent recurrence. Recovery was uneventful.