Human placenta-derived mesenchymal stem cells transplantation in patients with acute respiratory distress syndrome (ARDS) caused by COVID-19 (phase I clinical trial): safety profile assessment

BACKGROUND

High morbidity and mortality rates of the COVID-19 pandemic have made it a global health priority. Acute respiratory distress syndrome (ARDS) is one of the most important causes of death in COVID-19 patients. Mesenchymal stem cells have been the subject of many clinical trials for the treatment of ARDS because of their immunomodulatory, anti-inflammatory, and regenerative potentials. The aim of this phase I clinical trial was the safety assessment of allogeneic placenta-derived mesenchymal stem cells (PL-MSCs) intravenous injection in patients with ARDS induced by COVID-19.

METHODS

We enrolled 20 patients suffering from ARDS caused by COVID-19 who had been admitted to the intensive care unit. PL-MSCs were isolated and propagated using a xeno-free/GMP compliant protocol. Each patient in the treatment group (N = 10) received standard treatment and a single dose of 1 × 10⁶ cells/kg PL-MSCs intravenously. The control groups (N = 10) only received the standard treatment. Clinical signs and laboratory tests were evaluated in all participants at the baseline and during 28 days follow-ups.

RESULTS

No adverse events were observed in the PL-MSC group. Mean length of hospitalization, serum oxygen saturation, and other clinical and laboratory parameters were not significantly different in the two groups (p > 0.05).

CONCLUSION

Our results demonstrated that intravenous administration of PL-MSCs in patients with COVID-19 related ARDS is safe and feasible. Further studies whit higher cell doses and repeated injections are needed to evaluate the efficacy of this treatment modality.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials (IRCT); IRCT20200621047859N4. Registered 1 March 2021, https://en.irct.ir/trial/52947 .

Quantifying the size-resolved dynamics of indoor bioaerosol transport and control

Understanding the bioaerosol dynamics of droplets and droplet nuclei emitted during respiratory activities is important for understanding how infectious diseases are transmitted and potentially controlled. To this end, we conducted experiments to quantify the size-resolved dynamics of indoor bioaerosol transport and control in an unoccupied apartment unit operating under four different HVAC particle filtration conditions. Two model organisms (Escherichia coli K12 and bacteriophage T4) were aerosolized under alternating low and high flow rates to roughly represent constant breathing and periodic coughing. Size-resolved aerosol sampling and settle plate swabbing were conducted in multiple locations. Samples were analyzed by DNA extraction and quantitative polymerase chain reaction (qPCR). DNA from both organisms was detected during all test conditions in all air samples up to 7 m away from the source, but decreased in magnitude with the distance from the source. A greater fraction of T4 DNA was recovered from the aerosol size fractions smaller than 1 μm than E. coli K12 at all air sampling locations. Higher efficiency HVAC filtration also reduced the amount of DNA recovered in air samples and on settle plates located 3-7 m from the source.

Characteristic features of cutaneous melanoma in a dermatology referral centre in Tehran, Iran

BACKGROUND/OBJECTIVES

The characteristics of cutaneous melanoma in the Middle-Eastern countries is poorly described. Therefore we conducted this study to determine the characteristics of melanoma in Iran.

METHODS

A retrospective, cross sectional study of melanoma patients seen at a tertiary referral centre, Iran, from May 2004 to October 2014. Clinical data included age and gender of the patients at the time of diagnosis, tumour location and tumour size. Histological characteristics included Breslow thickness, Clark level and subtype of tumour.

RESULTS

A total of 450 cases of melanoma with a male/female ratio of 1.1:1 were reviewed. The mean age of patients was 57.5 years. The most frequent histological subtypes were acral lentiginous melanoma (30%) and lentigo maligna melanoma (29%). In 215 cases (49%) the tumour was located on the extremities. The second most common site was the face. Tumour invasion was mainly at Clark level III and IV. The mean Breslow thickness was 2.8 mm; 143 (38%) melanomas had a Breslow thickness less than 1 mm (T1) and 86 (23%) were more than 4 mm (T4).

CONCLUSION

This study indicates that clinical and histological features of melanoma in Iranians (who are mainly of skin phototypes 3-4) are different from those observed in Western countries. Further cohort studies are required to evaluate the role of ethnic and environmental risk factors for melanoma in different populations.

Severity of symptoms, physical functioning and satisfaction in patients with lumbar spinal stenosis: a validation study of the Iranian version of the Swiss Spinal Stenosis Score

AIM

A common cause of low back pain is lumbar spinal stenosis (LSS). The Swiss Spinal Stenosis Score (SSS) is a well-known questionnaire that measures the severity of symptoms, physical functioning and patient's satisfaction in lumbar spinal stenosis. This study aimed to translate and validate the SSS in Iran.

METHODS

A prospective clinical validation study was performed. Forward-backward procedure was applied to translate the original questionnaires into Persian. A sample of patients with lumbar spinal stenosis completed the questionnaire twice: at pre- and postoperative (6 months follow-up) assessments. To test reliability the internal consistency was assessed by the Cronbach's alpha coefficient. Validity was evaluated using the known groups comparison. In addition the Oswestry Disability Index was used to perform convergent validity.

RESULTS

In all 121 patients were entered into the study. The mean age of patients was 62.3 (SD=10.2) years. The Cronbach's alpha coefficient for the SSS was 0.88. Validity was performed by known groups analysis and showed satisfactory results. The instrument discriminated well between the subgroups of patients who differed in age, severity of lumbar spinal stenosis, and the Self-Paced Walking Test (SPWT). The change in the Oswestry Disability Index strongly correlated with the change in patients' scores on the SSS; lending support to its good convergent validity (r=0.82; P<0.001).

CONCLUSION

The Iranian version of Swiss Spinal Stenosis Score performed well and the findings suggest that it is a valid measure of symptoms, physical functioning and satisfaction among patients with lumbar spinal stenosis.

Does bone marrow-derived mesenchymal stem cell transfusion prevent antisperm antibody production after traumatic testis rupture?

OBJECTIVE

To determine whether transfusion of mesenchymal stem cells (MSCs) could prevent humoral immune response and autoimmunization against sperms after traumatic testis rupture.

METHODS

Immunomodulatory properties of MSCs have been evaluated by a prospective cohort on 50 adult BALB/c mice. In each interventional arms of study, controlled testis rupture and surgical repair were exerted. In addition to tissue repair, single dose of 5×10(5) MSCs labeled by green fluorescent protein was delivered intravenously to 20 cases (cell therapy group). After euthanizing, seroconversion of antisperm antibody (ASA) was compared between 2 interventional groups as response of humoral immune system. Lung and testis tissues were examined for green fluorescent protein-positive cells to assess whether presence of stem cells is correlated with seroconversion rates.

RESULTS

Six cases had been lost during the study. Fourteen of 16 mice in cell therapy control group formed ASA (87.5%) but 6 of 18 mice (33.3%) in cell therapy group were immunized and formed ASA (P=.002). Transplanted cells were traced in lungs of 55% (n=10) of cell therapy group and none were found in trauma site. Small volume of mice blood was our main limitation to trace seroconversion or quantitative measurement of ASA in each case.

CONCLUSION

In this in vivo model of autoimmune infertility, bone marrow-derived MSC transfusion showed immunosuppressive effects on antibody production. Considering immunomodulatory properties of MSCs even in allogeneic settings, novel clinical application should be investigated further.

Hemodynamic factors affecting the suitability of the donated heart and kidney for transplantation

BACKGROUND

Due to the loss of autonomic nervous system, precise control of the hemodynamic status in dead brain potential donors presents a clinical dilemma. In these patients, due to head trauma and cerebral edema, fluids administration is restricted. Moreover, the decreased central venous pressure may put the viability of the organs at risk.

OBJECTIVE

To investigate hemodynamic factors affecting the suitability of the donated heart and kidney for transplantation.

METHODS

Data were retrospectively collected from the maintained databases of all dead-brain donors (DBDs) admitted to our organ procurement unit (OPU) ICU between 1999 and 2008. In this study, laboratory variables in addition to demographic data were collected. The time between donor entrance to the DBD ICU and organ procurement, vital signs, hourly urine output, amount of IV fluid administered, and the dosage of vasopressor and desmopressin were recorded. The end-point of the study was organ suitability for organ retrieval.

RESULTS

A total of 132 dead brain donors were studied. The mean±SD age of the donors was 26.3±12.2 years. The main cause of brain death was multiple trauma (53%). The organ retrieval rate was 82.6% for the kidney, 59.8% for the liver, and 53% for the heart. 83 (63%) and 106 (80.3%) donors had suitable hearts and kidneys, respectively. 66 cases did not receive desmopressin (50.4%) at all. The mean±SD dose of desmopressin the donors received was 7±1 µg. There was a significant association between the suitability of these two organs for transplantation and the dosage of the administered desmopressin and volume of IV solution the donors received.

CONCLUSION

Fluid therapy and administration of desmopressin can improve the number and quality of retrieved organs from dead brain donors.

Rotavirus and central nervous system symptoms: cause or contaminant? Case reports and review

Rotavirus is a common cause of severe gastroenteritis in children. In 2 patients with rotavirus gastroenteritis who developed encephalopathy, rotavirus RNA was detected in the cerebrospinal fluid (CSF) by reverse transcription-polymerase chain reaction; in 1 patient, rotavirus RNA was detected on 2 occasions 3 weeks apart. There are increasing reports of cases in which patients who have seizures after an episode of rotavirus diarrhea have evidence of rotavirus in their CSF. A search of 2 large hospital discharge databases suggested that seizures are noted as part of the discharge diagnosis in the records of, at most, <4% of patients with rotavirus diarrhea versus 7% of patients with bacterial diarrhea. Although evidence suggesting that rotavirus is a cause of central nervous system sequelae remains inconclusive, the 2 case reports presented in this study further illustrate a possible association. Further study is required to determine whether detection of rotavirus in CSF represents a true pathogen, CSF contamination that occurs at the time of lumbar puncture or in the laboratory, or carriage of rotavirus RNA in trafficking lymphocytes.

Bloodstream infections in neonatal intensive care unit patients: results of a multicenter study

For identification of risk factors for bloodstream infection (BSI) among neonatal intensive care unit patients, prospective 6-month studies in three neonatal intensive care units were conducted. BSI was diagnosed in 42 of 376 (11.2%) enrolled infants. Pathogens included coagulase-negative staphylococci, Candida sp., Group B streptococci and Gram-negative species. Patients with BSIs were more likely to die during their neonatal intensive care unit stay than were patients who did not acquire BSIs (6 of 42 vs. 11 of 334, P = 0.007). BSI rate was highest in infants with birth weight < 1500 g (relative risk (RR) = 6.8, P < 0.001), those treated with H-2 blockers (RR = 4.2, P < 0.001) or theophylline (RR = 2.8, P < 0.001) and those with admission diagnoses referable to the respiratory tract (RR = 3.7, P < 0.001). Infants who developed BSI were more severely ill on admission than other infants (median physiologic stability index 13 vs. 10 (P < 0.001) and were of lower gestational age (28 vs. 35 weeks, P < 0.001). In logistic regression analysis, risk of BSI was independently associated only with very low birth weight, respiratory admission diagnoses and receipt of H-2 blockers. Risk of isolation of a pathogen from blood culture was independently associated with Broviac, umbilical vein or peripheral venous catheterization > 10, 7 or 3 days, respectively, at one insertion site. Rate of isolation of a pathogen was higher (9 of 59 (15%)) within 48 hours of a measurable serum interleukin 6 concentration than an interleukin 6 level of 0 pg/ml (10 of 159 (6%), P = 0.04).(ABSTRACT TRUNCATED AT 250 WORDS)

Pediatric streptococcal toxic shock syndrome

Two children who presented with fever, rash, and hypotension were found to have group A beta hemolytic streptococcal toxic shock syndrome. These cases are reported to remind physicians who care for acutely ill children that exotoxin-producing streptococci can produce clinical features and multisystem failure similar to staphylococcal toxic shock syndrome.

Reliability of polymerase chain reaction in the detection of human immunodeficiency virus infection in children

During a 3-year period we followed 128 human immunodeficiency virus (HIV) antibody-positive children ages 6 days to 11 years clinically and with an HIV diagnostic panel consisting of antibody (by enzyme-linked immunosorbent assay and confirmed by indirect fluorescence assay or Western blot), p24 antigen detection, HIV isolation from peripheral blood culture and molecular detection of HIV nucleic acids by polymerase chain reaction (PCR). The PCR procedure included 30 cycles of amplification using two separate gag primer pairs (SK38/39 and SK101/145), followed by detection with probes to areas amplified (SK19 and SK102). Results of PCR were available within 48 hours and were sensitive (97%) and specific (100%). PCR should be obtained on all children exposed perinatally, and aggressive management should be undertaken for those found to be positive.

Immunogenicity and reactogenicity of Haemophilus influenzae type b-meningococcus group B outer membrane protein conjugate vaccine in children 2-60 months of age

Haemophilus influenzae b - Neisseria meningitidis group B outer membrane protein conjugate vaccine (Hib-OMP) was given to 571 children 2-60 months of age. Two doses of Hib-OMP were given, 2 months apart, to 2-11 month old infants, and a single dose to children 12-60 month old. Sera were obtained from a subset of vaccinees at each immunization, and at follow-up 1 month and 1 year after immunization. Geometric mean antibody concentration (micrograms/ml) before and after full immunization were respectively 0.111 and 3.549 for 2-3 month old, 0.108 and 5.048 for 4-5 month old, 0.082 and 6.933 for 6-11 month old; they were 0.103 and 3.500 for 12-17 month old, 0.167 and 7.791 for 18-23 month old and 0.243 and 12.781 for children greater than or equal to 24 months. Detectable antibody (greater than or equal to 0.125 micrograms/ml) failed to develop in 2/399 (0.5%) after primary immunization, and 12/252 (4.8%) lost detectable antibody 1 year later. Six of these 12 infants were less than 12 month old. The vaccine was immunogenic as early as 3-5 months of age. The need for booster immunization needs to be assessed.

Randomized comparative study of ampicillin/sulbactam vs. ceftriaxone for treatment of soft tissue and skeletal infections in children

In a prospective study 105 children hospitalized with soft tissue infection, 11 children with suppurative arthritis and 9 children with osteomyelitis were treated with either parenterally administered ampicillin/sulbactam or ceftriaxone. Treatment was randomized using a computer-generated table in a 2:1 fashion: 84 patients received ampicillin/sulbactam and 41 patients received ceftriaxone. Organisms isolated from wound site or blood cultures included Staphylococcus aureus (33), Streptococcus pyogenes (19), Haemophilus influenzae (9) including 4 beta-lactamase-positive organisms, Streptococcus pneumoniae (5), Neisseria gonorrhoeae (3) and 9 other organisms. Clinical and bacteriologic response was satisfactory in 100% of the ampicillin/sulbactam-treated patients and in 93% of the ceftriaxone-treated patients. Two patients with S. aureus infections treated with ceftriaxone had a delayed response and required change in therapy to parenterally administered oxacillin. Ampicillin/sulbactam represents a potentially useful single agent for the treatment of cellulitis and bone or joint infections in pediatric patients.